Evidence that bovine forebrain embryonic zinc finger-like gene influences immune response associated with mastitis resistance.
AuthorsSugimoto M,Fujikawa A,Womack JE,Sugimoto Y
JournalProceedings of the National Academy of Sciences of the United States of America
PubMed ID16611727
Mastitis, a mammary gland inflammation in response to bacterial infection, is a major problem in the dairy industry. We found that cows susceptible to mastitis have a three-base insertion in a glycine-coding stretch of the gene for forebrain embryonic zinc finger-like (FEZL), a transcription factor with a role in neuronal ... More
Characterization of aquaporin-6 as a nitrate channel in mammalian cells. Requirement of pore-lining residue threonine 63.
Aquaporins (AQP) were originally regarded as plasma membrane channels that are freely permeated by water or small uncharged solutes but not by ions. Unlike other aquaporins, AQP6 overexpressed in Xenopus laevis oocytes was previously found to exhibit Hg2+ or pH-activated ion conductance. AQP6 could not be analyzed electrophysiologically in mammalian ... More
Folding of the striated muscle myosin motor domain.
Authors Chow Diana; Srikakulam Rajani; Chen Ying; Winkelmann Donald A;
JournalJ Biol Chem
PubMed ID12110670
'We have investigated the folding of the myosin motor domain using a chimera of an embryonic striated muscle myosin II motor domain fused on its COOH terminus to a thermal stable, fast folding variant of green fluorescent protein (GFP). In in vitro expression assays, the GFP domain of the chimeric ... More
Mammalian cell penetration, siRNA transfection, and DNA transfection by supercharged proteins.
AuthorsMcNaughton BR, Cronican JJ, Thompson DB, Liu DR,
JournalProc Natl Acad Sci U S A
PubMed ID19307578
'Nucleic acid reagents, including small interfering RNA (siRNA) and plasmid DNA, are important tools for the study of mammalian cells and are promising starting points for the development of new therapeutic agents. Realizing their full potential, however, requires nucleic acid delivery reagents that are simple to prepare, effective across many ... More
Dynamic fluorescent imaging of human immunodeficiency virus type 1 gag in live cells by biarsenical labeling.
AuthorsRudner L, Nydegger S, Coren LV, Nagashima K, Thali M, Ott DE,
JournalJ Virol
PubMed ID15767407
'Human immunodeficiency virus type 1 (HIV-1) Gag is the primary structural protein of the virus and is sufficient for particle formation. We utilized the recently developed biarsenical-labeling method to dynamically observe HIV-1 Gag within live cells by adding a tetracysteine tag (C-C-P-G-C-C) to the C terminus of Gag in both ... More
Amino acid residues critical for endoplasmic reticulum export and trafficking of platelet-activating factor receptor.
AuthorsHirota N, Yasuda D, Hashidate T, Yamamoto T, Yamaguchi S, Nagamune T, Nagase T, Shimizu T, Nakamura M,
JournalJ Biol Chem
PubMed ID20007715
'Several residues are conserved in the transmembrane domains (TMs) of G-protein coupled receptors. Here we demonstrate that a conserved proline, Pro(247), in TM6 of platelet-activating factor receptor (PAFR) is required for endoplasmic reticulum (ER) export and trafficking after agonist-induced internalization. Alanine-substituted mutants of the conserved residues of PAFRs, including P247A, ... More
Positional cloning of the murine flavivirus resistance gene.
Authors Perelygin Andrey A; Scherbik Svetlana V; Zhulin Igor B; Stockman Bronislava M; Li Yan; Brinton Margo A;
JournalProc Natl Acad Sci U S A
PubMed ID12080145
'Inbred mouse strains exhibit significant differences in their susceptibility to viruses in the genus Flavivirus, which includes human pathogens such as yellow fever, Dengue, and West Nile virus. A single gene, designated Flv, confers this differential susceptibility and was mapped previously to a region of mouse chromosome 5. A positional ... More
Rrn3 phosphorylation is a regulatory checkpoint for ribosome biogenesis.
Authors Cavanaugh Alice H; Hirschler-Laszkiewicz Iwona; Hu Qiyue; Dundr Miroslav; Smink Tom; Misteli Tom; Rothblum Lawrence I;
JournalJ Biol Chem
PubMed ID12015311
'Cycloheximide inhibits ribosomal DNA (rDNA) transcription in vivo. The mouse homologue of yeast Rrn3, a polymerase-associated transcription initiation factor, can complement extracts from cycloheximide-treated mammalian cells. Cycloheximide inhibits the phosphorylation of Rrn3 and causes its dissociation from RNA polymerase I. Rrn3 interacts with the rpa43 subunit of RNA polymerase I, ... More
Akt-dependent Phosphorylation of p27Kip1 Promotes Binding to 14-3-3 and Cytoplasmic Localization.
Authors Fujita Naoya; Sato Saori; Katayama Kazuhiro; Tsuruo Takashi;
JournalJ Biol Chem
PubMed ID12042314
'In many human cancers, the cyclin-dependent kinase inhibitor p27(Kip1) is expressed at low or undetectable levels. The decreased p27(Kip1) expression allows cyclin-dependent kinase activity to cause cells to enter into S phase and correlates with poor patient survival. Inhibition of serine/threonine kinase Akt signaling by some pharmacological agents or by ... More
Caveolin regulates endocytosis of the muscle repair protein, dysferlin.
AuthorsHernández-Deviez DJ, Howes MT, Laval SH, Bushby K, Hancock JF, Parton RG,
JournalJ Biol Chem
PubMed ID18096699
'Dysferlin and Caveolin-3 are plasma membrane proteins associated with muscular dystrophy. Patients with mutations in the CAV3 gene show dysferlin mislocalization in muscle cells. By utilizing caveolin-null cells, expression of caveolin mutants, and different mutants of dysferlin, we have dissected the site of action of caveolin with respect to dysferlin ... More
Subcellular targeting of RGS9-2 is controlled by multiple molecular determinants on its membrane anchor, R7BP.
AuthorsSong JH, Waataja JJ, Martemyanov KA,
JournalJ Biol Chem
PubMed ID16574655
'RGS9-2, a member of the R7 RGS protein family of neuronal RGS (Regulators of G protein Signaling), is a critical regulator of G protein signaling. In striatal neurons, RGS9-2 is tightly associated with a novel palmitoylated protein - R7BP (R7 family Binding Protein). Here we report that R7BP acts to ... More
Functional analysis of FSP27 protein regions for lipid droplet localization, caspase-dependent apoptosis, and dimerization with CIDEA.
AuthorsLiu K, Zhou S, Kim JY, Tillison K, Majors D, Rearick D, Lee JH, Fernandez-Boyanapalli RF, Barricklow K, Houston MS, Smas CM,
JournalAm J Physiol Endocrinol Metab
PubMed ID19843876
'The adipocyte-specific protein FSP27, also known as CIDEC, is one of three cell death-inducing DFF45-like effector (CIDE) proteins. The first known function for CIDEs was promotion of apoptosis upon ectopic expression in mammalian cells. Recent studies in endogenous settings demonstrated key roles for CIDEs in energy metabolism. FSP27 is a ... More
Loss of PINK1 function promotes mitophagy through effects on oxidative stress and mitochondrial fission.
AuthorsDagda RK, Cherra SJ, Kulich SM, Tandon A, Park D, Chu CT,
JournalJ Biol Chem
PubMed ID19279012
'Mitochondrial dysregulation is strongly implicated in Parkinson disease. Mutations in PTEN-induced kinase 1 (PINK1) are associated with familial parkinsonism and neuropsychiatric disorders. Although overexpressed PINK1 is neuroprotective, less is known about neuronal responses to loss of PINK1 function. We found that stable knockdown of PINK1 induced mitochondrial fragmentation and autophagy ... More
Real-time visualization of HIV-1 GAG trafficking in infected macrophages.
AuthorsGousset K, Ablan SD, Coren LV, Ono A, Soheilian F, Nagashima K, Ott DE, Freed EO,
JournalPLoS Pathog
PubMed ID18369466
'HIV-1 particle production is driven by the Gag precursor protein Pr55(Gag). Despite significant progress in defining both the viral and cellular determinants of HIV-1 assembly and release, the trafficking pathway used by Gag to reach its site of assembly in the infected cell remains to be elucidated. The Gag trafficking ... More
Thiazolides, a new class of anti-influenza molecules targeting viral hemagglutinin at the post-translational level.
AuthorsRossignol JF, La Frazia S, Chiappa L, Ciucci A, Santoro MG,
JournalJ Biol Chem
PubMed ID19638339
'The emergence of highly contagious influenza A virus strains, such as the new H1N1 swine influenza, represents a serious threat to global human health. Efforts to control emerging influenza strains focus on surveillance and early diagnosis, as well as development of effective vaccines and novel antiviral drugs. Herein we document ... More
Mass spectrometric analysis of GAP-43/neuromodulin reveals the presence of a variety of fatty acylated species.
Authors Liang Xiquan; Lu Yun; Neubert Thomas A; Resh Marilyn D;
JournalJ Biol Chem
PubMed ID12105219
'GAP-43 (neuromodulin) is a protein kinase C substrate that is abundant in developing and regenerating neurons. Thioester-linked palmitoylation at two cysteines near the GAP-43 N terminus has been implicated in directing membrane binding. Here, we use mass spectrometry to examine the stoichiometry of palmitoylation and the molecular identity of the ... More
Molecular and Biochemical Characterization of Rat epsilon -N-Trimethyllysine Hydroxylase, the First Enzyme of Carnitine Biosynthesis.
Authors Vaz F M; Ofman R; Westinga K; Back J W; Wanders R J;
JournalJ Biol Chem
PubMed ID11431483
'epsilon-N-Trimethyllysine hydroxylase (EC ) is the first enzyme in the biosynthetic pathway of l-carnitine and catalyzes the formation of beta-hydroxy-N-epsilon-trimethyllysine from epsilon-N-trimethyllysine, a reaction dependent on alpha-ketoglutarate, Fe(2+), and oxygen. We purified the enzyme from rat kidney and sequenced two internal peptides by quadrupole-time-of-flight mass spectroscopy. The peptide sequences were ... More
Lithium Induces NF-kappa B Activation and Interleukin-8 Production in Human Intestinal Epithelial Cells.
Authors Nemeth Zoltan H; Deitch Edwin A; Szabo Csaba; Fekete Zoltan; Hauser Carl J; Hasko Gyorgy;
JournalJ Biol Chem
PubMed ID11756416
'Lithium has been documented to regulate apoptosis and apoptotic gene expression via NF-kappaB and mitogen-activated protein (MAP) kinase-dependent mechanisms. Since both NF-kappaB and MAP kinases are also important mediators of inflammatory gene expression, we investigated the effect of lithium on NF-kappaB- and MAP kinase-mediated inflammatory gene expression. Incubation of human ... More
Prolonged nuclear retention of activated extracellular signal-regulated kinase 1/2 is required for hepatocyte growth factor-induced cell motility.
'We examined the signaling pathway by which hepatocyte growth factor (HGF) induces cell motility, with special focus on the role of extracellular signal-regulated kinase (ERK) in the nucleus. We used Madin-Darby canine kidney cells overexpressing ERK2 because of their prominent motility response to HGF. HGF stimulation of the cells induces ... More
Requirement of p53 targets in chemosensitization of colonic carcinoma to death ligand therapy.
AuthorsWang S, El-Deiry WS,
JournalProc Natl Acad Sci U S A
PubMed ID14645705
'Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) exhibits specific tumoricidal activity and is under development for cancer therapy. Mismatch-repair-deficient colonic tumors evade TRAIL-induced apoptosis through mutational inactivation of Bax, but chemotherapeutics including Camptosar (CPT-11) restore TRAIL sensitivity. However, the signaling pathways in restoring TRAIL sensitivity remain to be elucidated. Here, we ... More
Epithelial inducible nitric-oxide synthase is an apical EBP50-binding protein that directs vectorial nitric oxide output.
Authors Glynne Paul A; Darling Katharine E A; Picot Joanna; Evans Thomas J;
JournalJ Biol Chem
PubMed ID12080081
'Nitric oxide (NO), produced via inducible NO synthase (iNOS), can modulate polarized epithelial processes such as solute transport. Given the high reactivity of NO, we hypothesized that optimal NO regulation of polarized epithelial functions is achieved through compartmentalization of iNOS, allowing local NO delivery to its molecular targets. Here, we ... More
Overexpression of trehalose synthase and accumulation of intracellular trehalose in 293H and 293FTetR:Hyg cells.
'A humanized clone containing the trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase (otsA/B) has been constructed. Using the Gateway Cloning System (Invitrogen, Inc.), the otsA/B genes have been placed under the control of the CMV promoter (pEXPcmv-otsA/B) or the CMV promoter and the tet operator (pEXP cmv TetO-otsA/B). The pEXPcmv-otsA/B clone has ... More
Fe65, a ligand of the Alzheimer's beta-amyloid precursor protein, blocks cell cycle progression by down-regulating thymidylate synthase expression.
'The functions of the Alzheimer''s beta-amyloid precursor protein (APP) and of its complex with the adaptor protein Fe65 are still unknown. We have demonstrated that Fe65 is also a nuclear protein and APP functions as an extranuclear anchor, thus preventing Fe65 nuclear translocation. According to this finding, it was also ... More
Reduction in intracellular calcium levels inhibits myoblast differentiation.
Authors Porter George A Jr; Makuck Ryan F; Rivkees Scott A;
JournalJ Biol Chem
PubMed ID12042317
'In myocytes, calcium plays an important role in intracellular signaling and contraction. However, the ability of calcium to modulate the differentiation of striated muscle cells is poorly understood. To examine this issue we studied C2C12 cells, which is a myoblast cell line that differentiates in vitro. First, we observed that ... More
Silencing of RNA helicase II/Gualpha inhibits mammalian ribosomal RNA production.
AuthorsHenning D, So RB, Jin R, Lau LF, Valdez BC,
JournalJ Biol Chem
PubMed ID14559904
'The intricate production of ribosomal RNA is well defined in yeast, but its complexity in higher organisms is barely understood. We recently showed that down-regulation of nucleolar protein RNA helicase II/Gualpha (RH-II/Gualpha or DDX21) in Xenopus oocytes inhibited processing of 20 S rRNA to 18 S and contributed to degradation ... More
Regulation of a xenobiotic sulfonation cascade by nuclear pregnane X receptor (PXR).
Authors Sonoda Junichiro; Xie Wen; Rosenfeld John M; Barwick Joyce L; Guzelian Philip S; Evans Ronald M;
JournalProc Natl Acad Sci U S A
PubMed ID12370413
'The nuclear receptor PXR (pregnane X receptor) protects the body from hepatotoxicity of secondary bile acids such as lithocholic acid (LCA) by inducing expression of the hydroxylating cytochrome P450 enzyme CYP3A and promoting detoxification. We found that activation of PXR also increases the activity and gene expression of the phase ... More
Positive and negative regulation of APP amyloidogenesis by sumoylation.
AuthorsLi Y, Wang H, Wang S, Quon D, Liu YW, Cordell B,
JournalProc Natl Acad Sci U S A
PubMed ID12506199
'Amyloid beta peptide (Abeta) generated from amyloid precursor protein (APP) is central to Alzheimer''s disease (AD). Signaling pathways affecting APP amyloidogenesis play critical roles in AD pathogenesis and can be exploited for therapeutic intervention. Here, we show that sumoylation, covalent modification of cellular proteins by small ubiquitin-like modifier (SUMO) proteins, ... More
Hyporesponsiveness to vaccination with Borrelia burgdorferi OspA in humans and in TLR1- and TLR2-deficient mice.
Authors Alexopoulou Lena; Thomas Venetta; Schnare Markus; Lobet Yves; Anguita Juan; Schoen Robert T; Medzhitov Ruslan; Fikrig Erol; Flavell Richard A;
JournalNat Med
PubMed ID12091878
'The Lyme disease vaccine is based on the outer-surface lipoprotein (OspA) of the pathogen Borrelia burgdorferi, and 95% of vaccine recipients develop substantial titers of antibodies against OspA. Here, we identified seven individuals with very low antibody titers after vaccination (low responders). The macrophages of low responders produced less tumor ... More
Random walk of processive, quantum dot-labeled myosin Va molecules within the actin cortex of COS-7 cells.
AuthorsNelson SR, Ali MY, Trybus KM, Warshaw DM,
JournalBiophys J
PubMed ID19619465
'Myosin Va (myoVa) is an actin-based intracellular cargo transporter. In vitro experiments have established that a single myoVa moves processively along actin tracks, but less is known about how this motor operates within cells. Here we track the movement of a quantum dot (Qdot)-labeled myoVa HMM in COS-7 cells using ... More
The 5-hydroxytryptamine(4a) receptor is palmitoylated at two different sites, and acylation is critically involved in regulation of receptor constitutive activity.
'We have reported recently that the mouse 5-hydroxytryptamine(4a) (5-HT(4(a))) receptor undergoes dynamic palmitoylation (Ponimaskin, E. G., Schmidt, M. F., Heine, M., Bickmeyer, U., and Richter, D. W. (2001) Biochem. J. 353, 627-663). In the present study, conserved cysteine residues 328/329 in the carboxyl terminus of the 5-HT(4(a)) receptor were identified ... More
Identification of Protein Arginine Methyltransferase 2 as a Coactivator for Estrogen Receptor alpha.
'In an attempt to isolate cofactors capable of influencing estrogen receptor alpha (ERalpha) transcriptional activity, we used yeast two-hybrid screening and identified protein arginine methyltransferase 2 (PRMT2) as a new ERalpha-binding protein. PRMT2 interacted directly with three ERalpha regions including AF-1, DNA binding domain, and hormone binding domain in a ... More
Amino-terminal Determinants of U-type Inactivation of Voltage-gated K+ Channels.
Authors Kurata Harley T; Soon Gordon S; Eldstrom Jodene R; Lu Grace W K; Steele David F; Fedida David;
JournalJ Biol Chem
PubMed ID12021261
'The T1 domain is a cytosolic NH(2)-terminal domain present in all Kv (voltage-dependent potassium) channels, and is highly conserved between Kv channel subfamilies. Our characterization of a truncated form of Kv1.5 (Kv1.5DeltaN209) expressed in myocardium demonstrated that deletion of the NH(2) terminus of Kv1.5 imparts a U-shaped inactivation-voltage relationship to ... More
Inhibitory activity of a heterochromatin-associated serpin (MENT) against papain-like cysteine proteinases affects chromatin structure and blocks cell proliferation.
Authors Irving James A; Shushanov Sain S; Pike Robert N; Popova Evgenya Y; Brömme Dieter; Coetzer Theresa H T; Bottomley Stephen P; Boulynko Iaroslava A; Grigoryev Sergei A; Whisstock James C;
JournalJ Biol Chem
PubMed ID11821386
'MENT (Myeloid and Erythroid Nuclear Termination stage-specific protein) is a developmentally regulated chromosomal serpin that condenses chromatin in terminally differentiated avian blood cells. We show that MENT is an effective inhibitor of the papain-like cysteine proteinases cathepsins L and V. In addition, ectopic expression of MENT in mammalian cells is ... More
Angiogenic oligosaccharides of hyaluronan induce multiple signaling pathways affecting vascular endothelial cell mitogenic and wound healing responses.
Authors Slevin Mark; Kumar Shant; Gaffney John;
JournalJ Biol Chem
PubMed ID12194965
'Hyaluronan (HA) is a large nonsulfated glycosaminoglycan and an important regulator of angiogenesis, in particular, the growth and migration of vascular endothelial cells. We have identified some of the key intermediates responsible for induction of mitogenesis and wound recovery. Treatment of bovine aortic endothelial cells with oligosaccharides of hyaluronan (o-HA) ... More
The identification and characterization of a noncontinuous calmodulin-binding site in noninactivating voltage-dependent KCNQ potassium channels.
'We show here that in a yeast two-hybrid assay calmodulin (CaM) interacts with the intracellular C-terminal region of several members of the KCNQ family of potassium channels. CaM co-immunoprecipitates with KCNQ2, KCNQ3, or KCNQ5 subunits better in the absence than in the presence of Ca2+. Moreover, in two-hybrid assays where ... More
Identification of a Specific Molecular Repressor of the Peroxisome Proliferator-activated Receptor gamma Coactivator-1 alpha (PGC-1alpha ).
Authors Ichida Masaru; Nemoto Shino; Finkel Toren;
JournalJ Biol Chem
PubMed ID12397057
'The nuclear co-activator PGC-1alpha is a pivotal regulator of numerous pathways controlling both metabolism and overall energy homeostasis. Inappropriate increases in PGC-1alpha activity have been linked to a number of pathological conditions including heart failure and diabetes mellitus. Previous studies (Puigserver, P., Adelmant, G., Wu, Z., Fan, M., Xu, J., ... More
Role of loop structures of neuropsin in the activity of serine protease and regulated secretion.
'Neuropsin involved in neural plasticity in adult mouse brain is a member of the S1 (clan SA) family of serine proteases and forms characteristic surface loops surrounding the substrate-binding site (Kishi, T., Kato, M., Shimizu, T., Kato, K., Matsumoto, K., Yoshida, S., Shiosaka, S., and Hakoshima, T. (1999) J. Biol. ... More
Dual fluorescent labeling method to visualize plasmid DNA degradation.
'The efficiency of nonviral vectors for gene delivery may be enhanced by understanding the key barriers that limit the translocation of the therapeutic DNA into the nucleus. One such barrier is the instability of DNA in the cytoplasm. In this work, we have developed a method to dual-label plasmid DNA ... More
The spectrin cytoskeleton influences the surface expression and activation of human transient receptor potential channel 4 channels.
AuthorsOdell AF, Van Helden DF, Scott JL,
JournalJ Biol Chem
PubMed ID18048348
'Despite over a decade of research, only recently have the mechanisms governing transient receptor potential channel (TRPC) channel function begun to emerge, with an essential role for accessory proteins in this process. We previously identified a tyrosine phosphorylation event as critical in the plasma membrane translocation and activation of hTRPC4 ... More
Intensity calibration and automated cell cycle gating for high-throughput image-based siRNA screens of mammalian cells.
AuthorsPoon SS, Wong JT, Saunders DN, Ma QC, McKinney S, Fee J, Aparicio SA,
JournalCytometry A
PubMed ID18698634
'High-content microscopic screening systems are powerful tools for extracting quantitative multiparameter measures from large number of cells under numerous conditions. These systems perform well in applications that monitor the presence of objects, but lack in their ability to accurately estimate object intensities and summarize these findings due to variations in ... More
Phospholipase C-gamma is required for agonist-induced Ca2+ entry.
Authors Patterson Randen L; van Rossum Damian B; Ford Diana L; Hurt Kenneth J; Bae Sun Sik; Suh Pann Ghill; Kurosaki Tomohiro; Snyder Solomon H; Gill Donald L;
JournalCell
PubMed ID12437926
'We report here that PLC-gamma isoforms are required for agonist-induced Ca2+ entry (ACE). Overexpressed wild-type PLC-gamma1 or a lipase-inactive mutant PLC-gamma1 each augmented ACE in PC12 cells, while a deletion mutant lacking the region containing the SH3 domain of PLC-gamma1 was ineffective. RNA interference to deplete either PLC-gamma1 or PLC-gamma2 ... More
Genetic analysis of the herpes simplex virus type 1 UL20 protein domains involved in cytoplasmic virion envelopment and virus-induced cell fusion.
AuthorsMelancon JM, Foster TP, Kousoulas KG,
JournalJ Virol
PubMed ID15220406
'The herpes simplex virus type 1 UL20 protein (UL20p) is an important determinant for cytoplasmic virion morphogenesis and virus-induced cell fusion. To delineate the functional domains of the UL20 protein, we generated a panel of single and multiple (cluster) alanine substitutions as well as UL20p carboxyl-terminal truncations. The UL20 mutant ... More
Megakaryoblastic leukemia factor-1 transduces cytoskeletal signals and induces smooth muscle cell differentiation from undifferentiated embryonic stem cells.
AuthorsDu KL, Chen M, Li J, Lepore JJ, Mericko P, Parmacek MS,
JournalJ Biol Chem
PubMed ID14970199
'The SAP domain transcription factor myocardin plays a critical role in the transcriptional program regulating smooth muscle cell differentiation. In this report, we describe the capacity of myocardin to physically associate with megakaryoblastic leukemia factor-1 (MKL1) and characterize the function of MKL1 in smooth muscle cells (SMCs). The MKL1 gene ... More
A macromolecular complex of beta 2 adrenergic receptor, CFTR, and ezrin/radixin/moesin-binding phosphoprotein 50 is regulated by PKA.
AuthorsNaren AP, Cobb B, Li C, Roy K, Nelson D, Heda GD, Liao J, Kirk KL, Sorscher EJ, Hanrahan J, Clancy JP,
JournalProc Natl Acad Sci U S A
PubMed ID12502786
'It has been demonstrated previously that both the cystic fibrosis transmembrane conductance regulator (CFTR) and beta(2) adrenergic receptor (beta(2)AR) can bind ezrinradixinmoesin-binding phosphoprotein 50 (EBP50, also referred to as NHERF) through their PDZ motifs. Here, we show that beta(2) is the major adrenergic receptor isoform expressed in airway epithelia and ... More
Interacting effects of N-terminal variation and strex exon splicing on slo potassium channel regulation by calcium, phosphorylation, and oxidation.
Authors Erxleben Christian; Everhart Angela L; Romeo Charles; Florance Hannah; Bauer Mary Beth; Alcorta David A; Rossie Sandra; Shipston Michael J; Armstrong David L;
JournalJ Biol Chem
PubMed ID12016222
'We have investigated the structural basis for the phenotype of a native rat Slo (rSlo) potassium channel (BK(Ca); KCNMA1) in a rat pituitary cell line, GH(4)C(1). Opposing regulation of these calcium- and voltage-activated potassium channels by cAMP- and cGMP-dependent protein kinases requires an alternatively spliced exon (strex) of 59 amino ... More
The RasGAP N-terminal fragment generated by caspase cleavage protects cells in a Ras/PI3K/Akt-dependent manner that does not rely on NFkappa B activation.
Authors Yang Jiang-Yan; Widmann Christian;
JournalJ Biol Chem
PubMed ID11847220
'RasGAP, a regulator of Ras GTPase family members, is cleaved at low levels of caspase activity into an N-terminal fragment (fragment N) that generates potent anti-apoptotic signals. At higher levels of caspase activity, fragment N is further cleaved into two fragments that strongly potentiate apoptosis. RasGAP could thus function as ... More
Raf and akt mediate distinct aspects of sensory axon growth.
Authors Markus Annette; Zhong Jian; Snider William D;
JournalNeuron
PubMed ID12123609
'Nerve growth factor (NGF) induces dramatic axon growth from responsive embryonic peripheral neurons. However, the roles of the various NGF-triggered signaling cascades in determining specific axon morphological features remain unknown. Here, we transfected activated and inhibitory mutants of Trk effectors into sensory neurons lacking the proapoptotic protein Bax. This allowed ... More
A pro-apoptotic fragment of the p75 neurotrophin receptor is expressed in p75NTRExonIV null mice.
AuthorsPaul CE, Vereker E, Dickson KM, Barker PA,
JournalJ Neurosci
PubMed ID14985432
'The p75 neurotrophin receptor (p75NTR) regulates neuronal survival, apoptosis, and growth. Recent studies have reported that disruption of Exon IV produces a null mouse lacking all p75NTR gene products (p75NTRExonIV-/-), whereas mice lacking p75NTR Exon III (p75NTRExonIII-/-) maintain expression of an alternatively spliced form of p75NTR (s-p75NTR). Here, we report ... More
Identification and characterization of RRM-containing coactivator activator (CoAA) as TRBP-interacting protein, and its splice variant as a coactivator modulator (CoAM).
Authors Iwasaki T; Chin W W; Ko L;
JournalJ Biol Chem
PubMed ID11443112
'We previously cloned and characterized thyroid hormone receptor-binding protein (TRBP) as an LXXLL-containing general coactivator that associates with coactivator complexes through its C terminus. To identify protein cofactors for TRBP action, a Sos-Ras yeast two-hybrid cDNA library was screened using TRBP C terminus as bait. A novel coactivator was isolated, ... More
The activated glucocorticoid receptor modulates presumptive autoregulation of ribosomal protein S6 protein kinase, p70 S6K.
Authors Shah O Jameel; Iniguez-Lluhi Jorge A; Romanelli Angela; Kimball Scot R; Jefferson Leonard S;
JournalJ Biol Chem
PubMed ID11705993
'Protein metabolism in eukaryotic organisms is defined by a synthesis-degradation equilibrium that is subject to regulation by hormonal and nutritional signals. In mammalian tissues such as skeletal muscle, glucocorticoid hormones specify a catabolic response that influences both protein synthetic and protein degradative pathways. With regard to the former, glucocorticoids attenuate ... More
Akt1 regulates a JNK scaffold during excitotoxic apoptosis.
Authors Kim Albert H; Yano Hiroko; Cho Han; Meyer Debra; Monks Bob; Margolis Ben; Birnbaum Morris J; Chao Moses V;
JournalNeuron
PubMed ID12194869
'Cell survival is determined by a balance among signaling cascades, including those that recruit the Akt and JNK pathways. Here we describe a novel interaction between Akt1 and JNK interacting protein 1 (JIP1), a JNK pathway scaffold. Direct association between Akt1 and JIP1 was observed in primary neurons. Neuronal exposure ... More
5-Hydroxytryptamine 4(a) receptor is coupled to the Galpha subunit of heterotrimeric G13 protein.
'Serotonin (5-hydroxytryptamine (5-HT)) is an important neurotransmitter that regulates multiple events in the central nervous system. Many of the 5-HT functions are mediated via G protein-coupled receptors that are coupled to multiple heterotrimeric G proteins, including G(s), G(i), and G(q) subfamilies (Martin, G. R., Eglen, R. M., Hamblin, M. W., ... More
Salt-inducible Kinase Represses cAMP-dependent Protein Kinase-mediated Activation of Human Cholesterol Side Chain Cleavage Cytochrome P450 Promoter through the CREB Basic Leucine Zipper Domain.
Authors Doi Junko; Takemori Hiroshi; Lin Xing-Zi; Horike Nanao; Katoh Yoshiko; Okamoto Mitsuhiro;
JournalJ Biol Chem
PubMed ID11864972
'Salt-inducible kinase (SIK), one of the serine/threonine protein kinases, was transiently expressed in Y1 cells during the early phase of the ACTH/cAMP-dependent protein kinase (PKA)-mediated signal transduction. The overexpression of SIK(N), the SIK''s N-terminal kinase domain, repressed the expression of the side chain cleavage cytochrome P450 (CYP11A) gene. To elucidate ... More
Authors Wilcox-Adelman Sarah A; Denhez Fabienne; Goetinck Paul F;
JournalJ Biol Chem
PubMed ID12087088
'The cell-surface heparan sulfate proteoglycan syndecan-4 acts in conjunction with the alpha(5)beta(1) integrin to promote the formation of actin stress fibers and focal adhesions in fibronectin (FN)-adherent cells. Fibroblasts seeded onto the cell-binding domain (CBD) fragment of FN attach but do not fully spread or form focal adhesions. Activation of ... More
Redox regulation of Cdc25C.
Authors Savitsky Pavel A; Finkel Toren;
JournalJ Biol Chem
PubMed ID11925443
'The Cdc25 family of dual specific phosphatases are critical components of cell cycle progression and checkpoint control. Certain stresses such as ultraviolet light stimulate the rapid and selective destruction of Cdc25A protein through a Chk1 protein kinase-dependent pathway. We demonstrate that in contrast to cellular stresses previously examined, hydrogen peroxide ... More
Phosphatidylinositol 3-Kinase Controls Human Intestinal Epithelial Cell Differentiation by Promoting Adherens Junction Assembly and p38 MAPK Activation.
'The signaling pathways mediating human intestinal epithelial cell differentiation remain largely undefined. Phosphatidylinositol 3-kinase (PI3K) is an important modulator of extracellular signals, including those elicited by E-cadherin-mediated cell-cell adhesion, which plays an important role in maintenance of the structural and functional integrity of epithelia. In this study, we analyzed the ... More
The cytoplasmic tail dileucine motif LL572 determines the glycosylation pattern of membrane-type 1 matrix metalloproteinase.
'Membrane-type 1 matrix metalloproteinase (MT1-MMP; MMP-14) drives fundamental physiological and pathological processes, due to its ability to process a broad spectrum of substrates. Because subtle changes in its activity can produce profound physiological effects, MT1-MMP is tightly regulated. Currently, many aspects of this regulation remain to be elucidated. It has ... More
The human GINS complex associates with Cdc45 and MCM and is essential for DNA replication.
AuthorsAparicio T, Guillou E, Coloma J, Montoya G, Méndez J,
JournalNucleic Acids Res
PubMed ID19223333
'The GINS complex, originally discovered in Saccharomyces cerevisiae and Xenopus laevis, binds to DNA replication origins shortly before the onset of S phase and travels with the replication forks after initiation. In this study we present a detailed characterization of the human GINS (hGINS) homolog. Using new antibodies that allow ... More
Modulation of NMDA receptor-dependent calcium influx and gene expression through EphB receptors.
Authors Takasu Mari A; Dalva Matthew B; Zigmond Richard E; Greenberg Michael E;
JournalScience
PubMed ID11799227
'Protein-protein interactions and calcium entry through the N-methyl-d-aspartate (NMDA)-type glutamate receptor regulate synaptic development and plasticity in the central nervous system. The EphB receptor tyrosine kinases are localized at excitatory synapses where they cluster and associate with NMDA receptors. We identified a mechanism whereby EphBs modulate NMDA receptor function. EphrinB2 ... More
A Novel Diacylglycerol-lactone Shows Marked Selectivity in Vitro among C1 Domains of Protein Kinase C (PKC) Isoforms {alpha} and {delta} as Well as Selectivity for RasGRP Compared with PKC{alpha}.
AuthorsPu Y, Perry NA, Yang D, Lewin NE, Kedei N, Braun DC, Choi SH, Blumberg PM, Garfield SH, Stone JC, Duan D, Marquez VE,
JournalJ Biol Chem
PubMed ID15923197
'Although multiple natural products are potent ligands for the diacylglycerol binding C1 domain of protein kinase C (PKC), RasGRP, and related targets, the high conservation of C1 domains has impeded the development of selective ligands. We characterized here a diacylglycerol-lactone, 130C037, emerging from a combinatorial chemical synthetic strategy, which showed ... More
Low intracellular zinc impairs the translocation of activated NF-kappa B to the nuclei in human neuroblastoma IMR-32 cells.
Authors Mackenzie Gerardo G; Zago M Paola; Keen Carl L; Oteiza Patricia I;
JournalJ Biol Chem
PubMed ID12089148
'In the current work, we studied how variations in extracellular zinc concentrations modulate different steps involved in nuclear factor kappaB (NF-kappaB) activation in human neuroblastoma IMR-32 cells. Cells were incubated in media containing varying concentrations of zinc (1.5, 5, 15, and 50 microm). Within 3 h, the intracellular zinc content ... More
Nitric oxide-induced apoptosis in pancreatic beta cells is mediated by the endoplasmic reticulum stress pathway.
Authors Oyadomari S; Takeda K; Takiguchi M; Gotoh T; Matsumoto M; Wada I; Akira S; Araki E; Mori M;
JournalProc Natl Acad Sci U S A
PubMed ID11526215
'Excessive nitric oxide (NO) production in cytokine-activated beta cells has been implicated in beta cell disruption in type 1 diabetes. beta cells are very vulnerable to NO-induced apoptosis. However, the mechanism underlying this phenomenon is unclear. Low concentrations of NO that lead to apoptosis apparently do not cause severe DNA ... More
TRPC4 Can Be Activated by G-protein-coupled Receptors and Provides Sufficient Ca2+ to Trigger Exocytosis in Neuroendocrine Cells.
Authors Obukhov Alexander G; Nowycky Martha C;
JournalJ Biol Chem
PubMed ID11856742
Transient receptor potential (TRP) channels form a large family of plasma membrane cation channels. Mammalian members of the
A Requirement for the CD44 Cytoplasmic Domain for Hyaluronan Binding, Pericellular Matrix Assembly, and Receptor-mediated Endocytosis in COS-7 Cells.
Authors Jiang Hong; Peterson Richard S; Wang Weihua; Bartnik Eckart; Knudson Cheryl B; Knudson Warren;
JournalJ Biol Chem
PubMed ID11792695
CD44-negative COS-7 cells were transfected with expression constructs for CD44H (the predominant CD44 isoform), CD44E (epithelial isoform), or truncation mutant derivatives lacking the carboxyl-terminal 67 amino acids of the cytoplasmic domain, CD44HDelta67 and CD44EDelta67. The truncation mutant CD44HDelta67 is identical to a naturally occurring alternatively spliced ... More
Coculture methodologies for the study of Wnt signals.
AuthorsPlanutis K, Planutiene M, Holcombe RF,
JournalMethods Mol Biol
PubMed ID19099261
In vivo, responses to extracellular Wnt ligands are context dependent; the temporal characteristics and intensity of the signal are critical in determining the target cell response. In general, Wnt ligand-induced differentiation in mammalian cells requires several days of exposure. In order to better characterize Wnt-induced signaling in vitro, side-by-side and ... More
The calcium-binding loops of the tandem C2 domains of synaptotagmin VII cooperatively mediate calcium-dependent oligomerization.
Synaptotagmin VII (Syt VII), a proposed regulator for Ca2+-dependent exocytosis, showed a robust Ca2+-dependent oligomerization property via its two C2 domains (Fukuda, M., and Mikoshiba, K. (2001) J. Biol. Chem. 276, 27670-27676), but little is known about its structure or the critical residues directly involved in the oligomerization interface. In ... More
alpha-Actinin interacts with rapsyn in agrin-stimulated AChR clustering.
AuthorsDobbins GC, Luo S, Yang Z, Xiong WC, Mei L,
JournalMol Brain
PubMed ID19055765
: AChR is concentrated at the postjunctional membrane at the neuromuscular junction. However, the underlying mechanism is unclear. We show that alpha-actinin, a protein known to cross-link F-actin, interacts with rapsyn, a scaffold protein essential for neuromuscular junction formation. alpha-Actinin, rapsyn, and surface AChR form a ternary complex. Moreover, the ... More
Peg3/Pw1 is a mediator between p53 and Bax in DNA damage-induced neuronal death.
Authors Johnson Mark D; Wu Xiangwei; Aithmitti Nadia; Morrison Richard S;
JournalJ Biol Chem
PubMed ID11943780
Neuronal cell death after DNA damage requires p53 and Bax, but the mechanism by which p53 activation leads to Bax translocation and cell death in neurons is not known. We report here that Peg3/Pw1 is up-regulated after DNA damage in cortical neurons in a p53-dependent manner. Overexpression of Peg3/Pw1 leads ... More
Rapid induction of dendritic spine morphogenesis by trans-synaptic ephrinB-EphB receptor activation of the Rho-GEF kalirin.
AuthorsPenzes P, Beeser A, Chernoff J, Schiller MR, Eipper BA, Mains RE, Huganir RL,
JournalNeuron
PubMed ID12546821
The morphogenesis of dendritic spines, the major sites of excitatory synaptic transmission in the brain, is important in synaptic development and plasticity. We have identified an ephrinB-EphB receptor trans-synaptic signaling pathway which regulates the morphogenesis and maturation of dendritic spines in hippocampal neurons. Activation of the EphB receptor induces translocation ... More
Molecular determinants for the tissue specificity of SERMs.
Authors Shang Yongfeng; Brown Myles;
JournalScience
PubMed ID11923515
Selective estrogen receptor modulators (SERMs) mimic estrogen action in certain tissues while opposing it in others. The therapeutic effectiveness of SERMs such as tamoxifen and raloxifene in breast cancer depends on their antiestrogenic activity. In the uterus, however, tamoxifen is estrogenic. Here, we show that both tamoxifen and raloxifene induce ... More
Requirement of the p130CAS-Crk coupling for metastasis suppressor KAI1/CD82-mediated inhibition of cell migration.
AuthorsZhang XA, He B, Zhou B, Liu L,
JournalJ Biol Chem
PubMed ID12738793
KAI1/CD82 protein is a member of the tetraspanin superfamily and has been rediscovered as a cancer metastasis suppressor. The mechanism of KAI1/CD82-mediated suppression of cancer metastasis remains to be established. In this study, we found that migration of the metastatic prostate cancer cell line Du145 was substantially inhibited when KAI1/CD82 ... More
The Heat Shock Protein 90-CDC37 Chaperone Complex Is Required for Signaling by Types I and II Interferons.
AuthorsShang L, Tomasi TB,
JournalJ Biol Chem
PubMed ID16280321
Interferon signaling pathways are critical to both innate and adaptive mmunity. We have demonstrated here that the inhibition of heat shock protein 90 (Hsp90) functions by small interfering RNAs or chemical inhibitors blocking interferon-induced gene expression. Hsp90 was required for signal transducers and activators of transcription 1 phosphorylation, and in ... More
Retention of mutant low density lipoprotein receptor in ER leads to ER stress.
Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by mutations in the gene encoding the low density lipoprotein receptor (LDLR). More than 50% of these mutations lead to receptor proteins that are completely or partly retained in the endoplasmic reticulum (ER). The mechanisms involved in the intracellular processing and ... More
Chronic ethanol intake impairs insulin signaling in rats by disrupting Akt association with the cell membrane.
Chronic and excessive alcohol consumption is an important and modifiable risk factor for type 2 diabetes. We previously reported elevations in hepatic Class 1 Alcohol Dehydrogenase (ADH) expression in ethanol-fed rats correspondent with reduced levels of mature, nuclear SREBP-1, an insulin-induced transcriptional repressor of the ADH gene. In this report, ... More
Differentiation of mouse embryonic stem cells following RNAi-mediated silencing of OCT4 and Nanog.
AuthorsHough SR, Clements I, Welch PJ, Wiederholt KA,
JournalStem Cells
PubMed ID16456133
RNAi holds great promise as a tool to study the basic biology of stem cells or to direct differentiation in a specific manner. Barriers to achieving efficient and specific gene silencing in RNAi experiments include limitations in transfection efficiency and in the efficacy and specificity of RNAi silencing effectors. Here, ... More
The expression of Sprouty1, an inhibitor of fibroblast growth factor signal transduction, is decreased in human prostate cancer.
AuthorsKwabi-Addo B, Wang J, Erdem H, Vaid A, Castro P, Ayala G, Ittmann M,
JournalCancer Res
PubMed ID15256439
A considerable body of evidence indicates that alterations of fibroblast growth factors (FGFs) and their receptors contribute to prostate cancer progression. Recently, a new family of regulators of FGF activity has been identified. The Sprouty gene family negatively regulates FGF signaling in a variety of systems and could potentially limit ... More
AuthorsZhang Y, Ma K, Sadana P, Chowdhury F, Gaillard S, Wang F, McDonnell DP, Unterman TG, Elam MB, Park EA,
JournalJ Biol Chem
PubMed ID17079227
The pyruvate dehydrogenase complex (PDC) catalyzes the conversion of pyruvate to acetyl-CoA in mitochondria and is a key regulatory enzyme in the oxidation of glucose to acetyl-CoA. Phosphorylation of PDC by the pyruvate dehydrogenase kinases (PDK2 and PDK4) inhibits PDC activity. Expression of the PDK genes is elevated in diabetes ... More
Endocytic function, glycosaminoglycan specificity, and antibody sensitivity of the recombinant human 190-kDa hyaluronan receptor for endocytosis (HARE).
AuthorsHarris EN, Weigel JA, Weigel PH,
JournalJ Biol Chem
PubMed ID15208308
The human hyaluronan receptor for endocytosis (hHARE) mediates the endocytic clearance of hyaluronan (HA) and chondroitin sulfate from lymph fluid and blood. Two hHARE isoforms (190 and 315 kDa) are present in sinusoidal endothelial cells of liver, spleen, and lymph nodes (Zhou, B., McGary, C. T., Weigel, J. A., Saxena, ... More
Clinico-pathological rescue of a model mouse of Huntington's disease by siRNA.
AuthorsWang YL, Liu W, Wada E, Murata M, Wada K, Kanazawa I,
JournalNeurosci Res
PubMed ID16095740
Huntington's disease (HD) is an autosomal dominant inheritable neurodegenerative disorder currently without effective treatment. It is caused by an expanded polyglutamine (poly Q) tract in the corresponding protein, huntingtin (htt), and therefore suppressing the huntingtin expression in brain neurons is expected to delay the onset and mitigate the severity of ... More
Concurrent versus individual binding of HuR and AUF1 to common labile target mRNAs.
AuthorsLal A, Mazan-Mamczarz K, Kawai T, Yang X, Martindale JL, Gorospe M,
JournalEMBO J
PubMed ID15257295
RNA-binding proteins HuR and AUF1 bind to many common AU-rich target mRNAs and exert opposing influence on target mRNA stability, but the functional interactions between HuR and AUF1 have not been systematically studied. Here, using common target RNAs encoding p21 and cyclin D1, we provide evidence that HuR and AUF1 ... More
AMP-activated protein kinase regulates HNF4alpha transcriptional activity by inhibiting dimer formation and decreasing protein stability.
AuthorsHong YH, Varanasi US, Yang W, Leff T,
JournalJ Biol Chem
PubMed ID12740371
AMP-activated protein kinase (AMPK) is the central component of a cellular signaling system that regulates multiple metabolic enzymes and pathways in response to reduced intracellular energy levels. The transcription factor hepatic nuclear factor 4alpha (HNF4alpha) is an orphan nuclear receptor that regulates the expression of genes involved in energy metabolism ... More
RFPL4 interacts with oocyte proteins of the ubiquitin-proteasome degradation pathway.
AuthorsSuzumori N, Burns KH, Yan W, Matzuk MM,
JournalProc Natl Acad Sci U S A
PubMed ID12525704
Oocyte meiosis and early mitotic divisions in developing embryos rely on the timely production of cell cycle regulators and their clearance via proteasomal degradation. Ret Finger Protein-Like 4 (Rfpl4), encoding a RING finger-like protein with a B30.2 domain, was discovered during an in silico search for germ cell-specific genes. To ... More
Transmembrane phosphoprotein Cbp regulates the activities of Src-family tyrosine kinases.
AuthorsKawabuchi M, Satomi Y, Takao T, Shimonishi Y, Nada S, Nagai K, Tarakhovsky A, Okada M
JournalNature
PubMed ID10801129
The Src family of protein tyrosine kinases (Src-PTKs) is important in the regulation of growth and differentiation of eukaryotic cells. The activity of Src-PTKs in cells of different types is negatively controlled by Csk, which specifically phosphorylates a conserved regulatory tyrosine residue at the carboxy-terminal tail of the Src-PTKs. Csk ... More
Novel GC-rich DNA-binding compound produced by a genetically engineered mutant of the mithramycin producer Streptomyces argillaceus exhibits improved transcriptional repressor activity: implications for cancer therapy.
AuthorsAlbertini V, Jain A, Vignati S, Napoli S, Rinaldi A, Kwee I, Nur-e-Alam M, Bergant J, Bertoni F, Carbone GM, Rohr J, Catapano CV,
JournalNucleic Acids Res
PubMed ID16571899
The aureolic acid antibiotic mithramycin (MTM) binds selectively to GC-rich DNA sequences and blocks preferentially binding of proteins, like Sp1 transcription factors, to GC-rich elements in gene promoters. Genetic approaches can be applied to alter the MTM biosynthetic pathway in the producing microorganism and obtain new products with improved pharmacological ... More
Improvements in siRNA properties mediated by 2'-deoxy-2'-fluoro-beta-D-arabinonucleic acid (FANA).
AuthorsDowler T, Bergeron D, Tedeschi AL, Paquet L, Ferrari N, Damha MJ,
JournalNucleic Acids Res
PubMed ID16554553
RNA interference (RNAi) has emerged recently as an efficient mechanism for specific gene silencing. Short double-stranded small interfering RNAs (siRNAs) are now widely used for cellular or drug target validation; however, their use for silencing clinically relevant genes in a therapeutic setting remains problematic because of their unfavourable metabolic stability ... More
IpgB1 is a novel Shigella effector protein involved in bacterial invasion of host cells. Its activity to promote membrane ruffling via Rac1 and Cdc42 activation.
AuthorsOhya K, Handa Y, Ogawa M, Suzuki M, Sasakawa C,
JournalJ Biol Chem
PubMed ID15849186
Shigella, the causative agent of bacillary dysentery, is capable of inducing the large scale membrane ruffling required for the bacterial invasion of host cells. Shigella secrete a subset of effectors via the type III secretion system (TTSS) into the host cells to induce membrane ruffling. Here, we show that IpgB1 ... More
Disrupted-in-Schizophrenia-1 (DISC-1): mutant truncation prevents binding to NudE-like (NUDEL) and inhibits neurite outgrowth.
AuthorsOzeki Y, Tomoda T, Kleiderlein J, Kamiya A, Bord L, Fujii K, Okawa M, Yamada N, Hatten ME, Snyder SH, Ross CA, Sawa A,
JournalProc Natl Acad Sci U S A
PubMed ID12506198
Disrupted-in-Schizophrenia-1 (DISC-1) is a gene whose mutant truncation is associated with major psychiatric illness with a predominance of schizophrenic symptomatology. We have cloned and characterized rodent DISC-1. DISC-1 expression displays pronounced developmental regulation with the highest levels in late embryonic life when the cerebral cortex develops. In yeast two-hybrid analyses, ... More
The activity of siRNA in mammalian cells is related to structural target accessibility: a comparison with antisense oligonucleotides.
AuthorsKretschmer-Kazemi Far R, Sczakiel G,
JournalNucleic Acids Res
PubMed ID12888501
The biological activity of siRNA seems to be influenced by local characteristics of the target RNA, including local RNA folding. Here, we investigated quantitatively the relationship between local target accessibility and the extent of inhibition of the target gene by siRNA. Target accessibility was assessed by a computational approach that ... More
An eight residue fragment of an acyl carrier protein suffices for post-translational introduction of fluorescent pantetheinyl arms in protein modification in vitro and in vivo.
AuthorsZhou Z, Koglin A, Wang Y, McMahon AP, Walsh CT,
JournalJ Am Chem Soc
PubMed ID18593165
Genetically encoded tags for tracking a given protein continue to be of great interest in a multitude of in vitro and in vivo contexts. Acyl carrier proteins, both free-standing and as embedded 80-100 residue domains, contain a specific serine side chain that undergoes post-translational pantetheinylation from CoASH as donor substrate. ... More
beta-Galactosidase activity assay using far-red-shifted fluorescent substrate DDAOG.
AuthorsGong H, Zhang B, Little G, Kovar J, Chen H, Xie W, Schutz-Geschwender A, Olive DM,
JournalAnal Biochem
PubMed ID19103143
beta-Galactosidase (beta-gal) is commonly used as a reporter gene in biological research, and a wide variety of substrates have been developed to assay its activity. One substrate, 9H-(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl) beta-d-galactopyranoside (DDAOG), can be cleaved by beta-gal to produce 7-hydroxy-9H(I,3-dichloro-9,9-dimethylacridin-2-one) (DDAO). On excitation, DDAO generates a far-red-shifted fluorescent signal. Using this substrate, ... More
Ankyrin-G is a molecular partner of E-cadherin in epithelial cells and early embryos.
AuthorsKizhatil K, Davis JQ, Davis L, Hoffman J, Hogan BL, Bennett V,
JournalJ Biol Chem
PubMed ID17620337
E-cadherin is a ubiquitous component of lateral membranes in epithelial tissues and is required to form the first lateral membrane domains in development. Here, we identify ankyrin-G as a molecular partner of E-cadherin and demonstrate that ankyrin-G and beta-2-spectrin are required for accumulation of E-cadherin at the lateral membrane in ... More
Amplification of CD95 activation by caspase 8-induced endosomal acidification in rat hepatocytes.
AuthorsReinehr R, Sommerfeld A, Keitel V, Grether-Beck S, Haüssinger D,
JournalJ Biol Chem
PubMed ID18045865
Although in rat hepatocytes CD95 is predominantly located inside the cell with almost undetectable immunostaining at the plasma membrane, the addition of CD95-ligand (CD95L) induces hepatocyte apoptosis, which is preceded by a targeting and activation of intracellularly localized CD95 to the plasma membrane including formation of the death-inducing signaling complex. ... More
Defining mechanisms of actin polymerization and depolymerization during dendritic spine morphogenesis.
Dendritic spines are small protrusions along dendrites where the postsynaptic components of most excitatory synapses reside in the mature brain. Morphological changes in these actin-rich structures are associated with learning and memory formation. Despite the pivotal role of the actin cytoskeleton in spine morphogenesis, little is known about the mechanisms ... More
Automated organelle-based colocalization in whole-cell imaging.
AuthorsWoodcroft BJ, Hammond L, Stow JL, Hamilton NA,
JournalCytometry A
PubMed ID19746416
The use of fluorescence microscopy to investigate protein colocalization is an invaluable tool for understanding subcellular structures and their associated proteins. However, current techniques are largely limited to two-dimensional (2D) imaging and often require manual segmentation. Here, we present OBCOL, a methodology to automatically segment and quantify protein colocalization not ... More
Knockdown of mu-calpain in Fanconi anemia, FA-A, cells by siRNA restores alphaII spectrin levels and corrects chromosomal instability and defective DNA interstrand cross-link repair.
AuthorsZhang P, Sridharan D, Lambert MW,
JournalBiochemistry
PubMed ID20518497
We have previously shown that there is a deficiency in the structural protein, nonerythroid alpha spectrin (alphaIISp), in cells from patients with Fanconi anemia (FA). These studies indicate that this deficiency is due to the reduced stability of alphaIISp and correlates with a decreased level of repair of DNA interstrand ... More
Endogenous 24(S),25-epoxycholesterol fine-tunes acute control of cellular cholesterol homeostasis.
AuthorsWong J, Quinn CM, Gelissen IC, Brown AJ,
JournalJ Biol Chem
PubMed ID17981807
Certain oxysterols, when added to cultured cells, are potent regulators of cholesterol homeostasis, decreasing cholesterol synthesis and uptake and increasing cholesterol efflux. However, very little is known about whether or not endogenous oxysterol(s) plays a significant role in cholesterol homeostasis. 24(S),25-Epoxycholesterol (24,25EC) is unique among oxysterols in that it is ... More
Cleavage of von Willebrand Factor Requires the Spacer Domain of the Metalloprotease ADAMTS13.
AuthorsZheng X, Nishio K, Majerus EM, Sadler JE,
JournalJ Biol Chem
PubMed ID12791682
ADAMTS13 consists of a reprolysin-type metalloprotease domain followed by a disintegrin domain, a thrombospondin type 1 motif (TSP1), Cys-rich and spacer domains, seven more TSP1 motifs, and two CUB domains. ADAMTS13 limits platelet accumulation in microvascular thrombi by cleaving the Tyr1605-Met1606 bond in von Willebrand factor, and ADAMTS13 deficiency causes ... More
Resveratrol protects mitochondria against oxidative stress through AMP-activated protein kinase-mediated glycogen synthase kinase-3beta inhibition downstream of poly(ADP-ribose)polymerase-LKB1 pathway.
AuthorsShin SM, Cho IJ, Kim SG,
JournalMol Pharmacol
PubMed ID19620254
Arachidonic acid (AA, a proinflammatory fatty acid) in combination with iron promotes excess reactive oxygen species (ROS) production and exerts a deleterious effect on mitochondria. We have shown previously that activation of AMP-activated protein kinase (AMPK) protects hepatocytes from AA + iron-induced apoptosis. Resveratrol, a polyphenol in grapes, has beneficial ... More
Stroma-dependent apoptosis in clonal hematopoietic precursors correlates with expression of PYCARD.
The role of the marrow microenvironment in the pathophysiology of myelodysplastic syndromes (MDSs) remains controversial. Using stromal/hematopoietic cell cocultures, we investigated the effects of stroma-derived signals on apoptosis sensitivity in hematopoietic precursors. The leukemia-derived cell line KG1a is resistant to proapoptotic ligands. However, when cocultured with the human stromal cell ... More
Autophagy in neurite injury and neurodegeneration: in vitro and in vivo models.
Recent advances indicate that maintaining a balanced level of autophagy is critically important for neuronal health and function. Pathologic dysregulation of macroautophagy has been implicated in synaptic dysfunction, cellular stress, and neuronal cell death. Autophagosomes and autolysosomes are induced in acute and chronic neurological disorders including stroke, brain trauma, neurotoxin ... More