Metaxin is a component of a preprotein import complex in the outer membrane of the mammalian mitochondrion.
AuthorsArmstrong LC, Komiya T, Bergman BE, Mihara K, Bornstein P
JournalJ Biol Chem
PubMed ID9045676
'Metaxin, a novel gene located between the glucocerebrosidase and thrombospondin 3 genes in the mouse, is essential for survival of the postimplantation mouse embryo. In this study, the subcellular location, domain structure, and biochemical function of metaxin were investigated. Anti-recombinant metaxin antibodies recognized 35- and 70- kDa proteins in mitochondria ... More
Dual DNA binding specificity of ADD1/SREBP1 controlled by a single amino acid in the basic helix-loop-helix domain.
'Adipocyte determination- and differentiation-dependent factor 1 (ADD1), a member of the basic helix-loop-helix (bHLH) family of transcription factors, has been associated with both adipocyte differentiation and cholesterol homeostasis (in which case it has been termed SREBP1). Using PCR-amplified binding analysis, we demonstrate that ADD1/SREBP1 has dual DNA sequence specificity, binding ... More
Characterization of protein kinase A and protein kinase C phosphorylation of the N-methyl-D-aspartate receptor NR1 subunit using phosphorylation site-specific antibodies.
'Modulation of N-methyl-D-aspartate receptors in the brain by protein phosphorylation may play a central role in the regulation of synaptic plasticity. To examine the phosphorylation of the NR1 subunit of N- methyl-D-aspartate receptors in situ, we have generated several polyclonal antibodies that recognize the NR1 subunit only when specific serine ... More
Ca2+/calmodulin binds to and modulates P/Q-type calcium channels [see comments]
AuthorsLee A, Wong ST, Gallagher D, Li B, Storm DR, Scheuer T, Catterall WA
JournalNature
PubMed ID10335845
'Neurotransmitter release at many central synapses is initiated by an influx of calcium ions through P/Q-type calcium channels, which are densely localized in nerve terminals. Because neurotransmitter release is proportional to the fourth power of calcium concentration, regulation of its entry can profoundly influence neurotransmission. N- and P/Q-type calcium channels ... More
Oligomerization-dependent association of the SAM domains from Schizosaccharomyces pombe Byr2 and Ste4.
Authors Ramachander Ranjini; Kim Chongwoo A; Phillips Martin L; Mackereth Cameron D; Thanos Christopher D; McIntosh Lawrence P; Bowie James U;
JournalJ Biol Chem
PubMed ID12171939
'SAM (sterile alpha motif) domains are protein-protein interaction modules found in a large number of regulatory proteins. Byr2 and Ste4 are two SAM domain-containing proteins in the mating pheromone response pathway of the fission yeast, Schizosaccharomyces pombe. Byr2 is a mitogen-activated protein kinase kinase kinase that is regulated by Ste4. ... More
Dual recognition of the bacterial chemoreceptor by chemotaxis-specific domains of the CheR methyltransferase.
Authors Shiomi Daisuke; Zhulin Igor B; Homma Michio; Kawagishi Ikuro;
JournalJ Biol Chem
PubMed ID12101179
'Adaptation to persisting stimulation is required for highly sensitive detection of temporal changes of stimuli, and often involves covalent modification of receptors. Therefore, it is of vital importance to understand how a receptor and its cognate modifying enzyme(s) modulate each other through specific protein-protein interactions. In the chemotaxis of Escherichia ... More
Purification of human double-stranded RNA-specific editase 1 (hRED1) involved in editing of brain glutamate receptor B pre-mRNA.
AuthorsO'Connell MA, Gerber A, Keller W
JournalJ Biol Chem
PubMed ID8995285
'RNAs encoding subunits of glutamate-gated ion channel receptors are posttranscriptionally modified by RNA editing and alternative splicing. The change in amino acid sequence caused by RNA editing can affect both the kinetics and the permeability of the ion channel receptors to cations. Here, we report the purification of a 90-kDa ... More
Recognition by tryptophanyl-tRNA synthetases of discriminator base on tRNATrp from three biological domains.
Authors Guo Qing; Gong Qingguo; Tong Ka-Lok; Vestergaard Bente; Costa Annie; Desgres Jean; Wong Mansim; Grosjean Henri; Zhu Guang; Wong J Tze-Fei; Xue Hong;
JournalJ Biol Chem
PubMed ID11834741
'To study the recognition by tryptophanyl-tRNA synthetase (TrpRS) of tRNA(Trp) discriminator base, mutations were introduced into the discriminator base of Bacillus subtilis, Archeoglobus fulgidus, and bovine tRNA(Trp), representing the three biological domains. When B. subtilis, A. fulgidus, and human TrpRS were used to acylate these tRNA(Trp), two distinct preference profiles ... More
Regions on adenylyl cyclase that are necessary for inhibition of activity by beta gamma and G(ialpha) subunits of heterotrimeric G proteins
AuthorsWittpoth C, Scholich K, Yigzaw Y, Stringfield TM, Patel TB
JournalProc Natl Acad Sci U S A
PubMed ID10449730
'The two large cytoplasmic domains (C1 and C2) of adenylyl cyclases (AC), when expressed separately and mixed together, reconstitute enzyme activity that can be regulated by various modulators. Therefore, we have used the C1 or its C1a subdomain and C2 regions from type I AC (ACI) and type V AC ... More
Mutation at the catalytic site of topoisomerase I in CEM/C2, a human leukemia cell line resistant to camptothecin.
AuthorsFujimori A, Harker WG, Kohlhagen G, Hoki Y, Pommier Y
JournalCancer Res
PubMed ID7882333
'We developed previously a resistant cell line, CEM/C2, from the human leukemia cell line CCRF-CEM by stepwise selection in camptothecin. This cell line is 974-fold more resistant to camptothecin than parental cells. Resistance is only partially explained by 2-fold reductions in topoisomerase I protein and mRNA levels. We further investigated ... More
Comparison of kinetic properties between two mammalian ras p21 GDP/GTP exchange proteins, ras guanine nucleotide-releasing factor and smg GDP dissociation stimulation.
'The mammalian counterpart of the yeast ras p21 GDP/GTP exchange protein CDC25, ras GRF, was expressed in Escherichia coli and purified, and its kinetic properties were compared with those of another mammalian ras p21 GDP/GTP exchange protein, smg GDS. ras GRF was active on Ki- and Ha- ras p21s but ... More
Neutrophil phospholipase D is activated by a membrane-associated Rho family small molecular weight GTP-binding protein.
AuthorsBowman EP, Uhlinger DJ, Lambeth JD
JournalJ Biol Chem
PubMed ID8408000
'Phospholipase D in human neutrophil lysates is activated by GTP gamma S (guanosine 5''-O-(3-thiotriphosphate)), implying the participation of a GTP-binding protein. Reconstitution of GTP gamma S-dependent activity requires protein factors in both the plasma membrane and the cytosol (Olson, S. C., Bowman, E. P., and Lambeth, J. D. (1991) J. ... More
Characterization of a novel 23-kilodalton protein of unactive progesterone receptor complexes.
AuthorsJohnson JL, Beito TG, Krco CJ, Toft DO
JournalMol Cell Biol
PubMed ID8114727
'Immunoprecipitation of unactivated avian progesterone receptor results in the copurification of hsp90, hsp70, and three additional proteins, p54, p50, and p23. p23 is also present in immunoaffinity-purified hsp90 complexes along with hsp70 and another protein, p60. Antibody and cDNA probes for p23 were prepared in an effort to elucidate the ... More
Interaction between the insulin receptor and its downstream effectors. Use of individually expressed receptor domains for structure/function analysis.
AuthorsPaz K, Voliovitch H, Hadari YR, Roberts CT Jr, LeRoith D, Zick Y
JournalJ Biol Chem
PubMed ID8636129
'A structural analysis has been carried out to determine which part of the intracellular domain of the insulin receptor (IR) beta subunit is involved in direct interaction with the receptor substrates IRS-1 and Shc. Toward this end, the juxtamembrane (JM) domain (amino acids 943- 984) and the carboxyl-terminal (CT) region ... More
Arginine 343 and 350 are two active residues involved in substrate binding by human Type I D-myo-inositol 1,4,5,-trisphosphate 5- phosphatase.
AuthorsCommuni D, Lecocq R, Erneux C
JournalJ Biol Chem
PubMed ID8662625
'The crucial role of two reactive arginyl residues within the substrate binding domain of human Type I D-myo-inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) 5-phosphatase has been investigated by chemical modification and site-directed mutagenesis. Chemical modification of the enzyme by phenylglyoxal is accompanied by irreversible inhibition of enzymic activity. Our studies demonstrate that phenylglyoxal ... More
The plasmid RK2 initiation protein binds to the origin of replication as a monomer.
AuthorsToukdarian AE, Helinski DR, Perri S
JournalJ Biol Chem
PubMed ID8636140
'The TrfA protein encoded by the broad host range bacterial plasmid RK2 specifically binds to eight direct repeats (iterons) present at the plasmid replication origin to initiate DNA replication. Purified TrfA protein is largely in the form of a dimer, and using a dimerization test system that involves the fusion ... More
La proteins from Drosophila melanogaster and Saccharomyces cerevisiae: a yeast homolog of the La autoantigen is dispensable for growth.
AuthorsYoo CJ, Wolin SL
JournalMol Cell Biol
PubMed ID8035818
'The human autoantigen La is a 50-kDa protein which binds to the 3'' termini of virtually all nascent polymerase III transcripts. Experiments with mammalian transcription extracts have led to the proposal that the La protein is required for multiple rounds of transcription by RNA polymerase III (E. Gottlieb and J. ... More
Reggie-1 and reggie-2, two cell surface proteins expressed by retinal ganglion cells during axon regeneration.
AuthorsSchulte T, Paschke KA, Laessing U, Lottspeich F, Stuermer CA
JournalDevelopment
PubMed ID9053333
'Fish--in contrast to mammals--regenerate retinal ganglion cell axons when the optic nerve is severed. Optic nerve injury leads to reexpression of proteins, which typically are first expressed in newly differentiated retinal ganglion cells and axons. Here we identified two new proteins of fish retinal ganglion cells, reggie-1 and reggie-2, with ... More
The yeast La protein is required for the 3' endonucleolytic cleavage that matures tRNA precursors.
AuthorsYoo CJ, Wolin SL
JournalCell
PubMed ID9150139
'Although the La autoantigen binds to the 3'' ends of all nascent polymerase III transcripts, its function in vivo has long been unclear. Although S. cerevisiae cells lacking the La protein homolog Lhp1p are viable, cells containing a mutation that disrupts the anticodon stem of tRNA(Ser)CGA require Lhp1p for growth. ... More
When an ATPase is not an ATPase: at low temperatures the C-terminal domain of the ABC transporter CvaB is a GTPase.
AuthorsZhong X, Tai PC
JournalJ Bacteriol
PubMed ID9515899
'The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins which share a common function and a common nucleotide-binding domain. The CvaB protein from Escherichia coli is a member of the bacterial ABC exporter subfamily and is essential for the export of the peptide antibiotic colicin V. Here ... More
Immune hyperactivation of HIV-1-infected T cells mediated by Tat and the CD28 pathway.
AuthorsOtt M, Emiliani S, Van Lint C, Herbein G, Lovett J, Chirmule N, McCloskey T, Pahwa S, Verdin E
JournalScience
PubMed ID9045614
Human immunodeficiency virus-type 1 (HIV-1) infection is characterized by a chronic state of immune hyperactivation in patients. Infection of human peripheral blood lymphocytes with HIV-1 in vitro resulted in increased interleukin-2 (IL-2) secretion in response to T cell activation via the CD3 and CD28 receptors. Expression of the HIV-1 transactivator ... More
Cell cycle-dependent polar localization of chromosome partitioning proteins in Caulobacter crescentus.
AuthorsMohl DA, Gober JW
JournalCell
PubMed ID9054507
In the bacterium C. crescentus, the cellular homologs of plasmid partitioning proteins, ParA and ParB, localize to both poles of the predivisional cell following the completion of DNA replication. ParB binds to DNA sequences adjacent to the origin of replication suggesting that this region of the genome is tethered to ... More
Properties of H. volcanii tRNA intron endonuclease reveal a relationship between the archaeal and eucaryal tRNA intron processing systems.
AuthorsKleman-Leyer K, Armbruster DW, Daniels CJ
JournalCell
PubMed ID9200602
To better understand the relationship between archaeal and eucaryal tRNA introns and their processing systems, we have cloned the gene encoding the tRNA intron endonucleases from the archaeon H. volcanii. The gene encodes a 37 kDa protein that appears to be present as a homodimer under native conditions. Recombinant forms ... More
Cell cycle control by an essential bacterial two-component signal transduction protein.
AuthorsQuon KC, Marczynski GT, Shapiro L
JournalCell
PubMed ID8548829
Dividing cells must coordinate cell cycle events to ensure genetic stability. Here we identify an essential two-component signal transduction protein that controls multiple events in the Caulobacter cell cycle, including cell division, stalk synthesis, and cell cycle- specific transcription. This protein, CtrA, is homologous to response regulator transcription factors and ... More
Physical interaction between the herpes simplex virus 1 origin-binding protein and single-stranded DNA-binding protein ICP8.
AuthorsBoehmer PE, Lehman IR
JournalProc Natl Acad Sci U S A
PubMed ID8397405
We had previously demonstrated that the herpes simplex virus 1 (HSV-1) single-stranded DNA-binding protein (ICP8) can specifically stimulate the helicase activity of the HSV-1 origin-binding protein (UL9). We show here that this functional stimulation is a manifestation of a tight interaction between UL9 protein and ICP8. By using protein- affinity ... More
Osf2/Cbfa1: a transcriptional activator of osteoblast differentiation [see comments]
AuthorsDucy P, Zhang R, Geoffroy V, Ridall AL, Karsenty G
JournalCell
PubMed ID9182762
The osteoblast is the bone-forming cell. The molecular basis of osteoblast-specific gene expression and differentiation is unknown. We previously identified an osteoblast-specific cis-acting element, termed OSE2, in the Osteocalcin promoter. We have now cloned the cDNA encoding Osf2/Cbfa1, the protein that binds to OSE2. Osf2/Cbfa1 expression is initiated in the ... More
The LIN-2/LIN-7/LIN-10 complex mediates basolateral membrane localization of the C. elegans EGF receptor LET-23 in vulval epithelial cells.
AuthorsKaech SM, Whitfield CW, Kim SK
JournalCell
PubMed ID9753323
In C. elegans, the LET-23 receptor tyrosine kinase is localized to the basolateral membranes of polarized vulval epithelial cells. lin-2, lin- 7, and lin-10 are required for basolateral localization of LET-23, since LET-23 is mislocalized to the apical membrane in lin-2, lin-7, and lin-10 mutants. Yeast two-hybrid, in vitro binding, ... More
2-Hydroxycyclohexanecarboxyl Coenzyme A Dehydrogenase, an Enzyme Characteristic of the Anaerobic Benzoate Degradation Pathway Used by Rhodopseudomonas palustris
AuthorsDale A. Pelletier and Caroline S. Harwood*
JournalJ Bacteriol
PubMed ID10781543
A gene, badH, whose predicted product is a member of the short-chain dehydrogenase/reductase family of enzymes, was recently discovered during studies of anaerobic benzoate degradation by the photoheterotrophic bacterium Rhodopseudomonas palustris. Purified histidine-tagged BadH protein catalyzed the oxidation of2-hydroxycyclohexanecarboxyl coenzyme A (2-hydroxychc-CoA) to 2-ketocyclohexanecarboxyl-CoA. These compounds are proposed intermediates of ... More
Characterization of a DNA-binding protein implicated in transcription in wheat mitochondria
AuthorsIkeda TM, Gray MW
JournalMol Cell Biol
PubMed ID10567537
To investigate the transcriptional apparatus in wheat mitochondria, mitochondrial extracts were subjected to column chromatography and protein fractions were analyzed by in vitro transcription and mobility shift assays. Fractions eluting from DEAE-Sephacel between 0.2 and 0.3 M KCl displayed DNA-binding activity and supported specific transcription initiated from a wheat cox2 ... More
Molecular identification of human G-substrate, a possible downstream component of the cGMP-dependent protein kinase cascade in cerebellar Purkinje cells.
AuthorsEndo S, Suzuki M, Sumi M, Nairn AC, Morita R, Yamakawa K, Greengard P, Ito M
JournalProc Natl Acad Sci U S A
PubMed ID10051666
G-substrate, an endogenous substrate for cGMP-dependent protein kinase, exists almost exclusively in cerebellar Purkinje cells, where it is possibly involved in the induction of long-term depression. A G- substrate cDNA was identified by screening expressed sequence tag databases from a human brain library. The deduced amino acid sequence of human ... More
Microglial activation by Alzheimer amyloid precursor protein and modulation by apolipoprotein E.
AuthorsBarger SW, Harmon AD
JournalNature
PubMed ID9278049
A role for beta-amyloid precursor protein (beta-APP) in the development of Alzheimer's disease has been indicated by genetics, and many conditions in which beta-APP is raised have been associated with an increased risk of Alzheimer's disease or an Alzheimer's-like pathology. Inflammatory events may also contribute to Alzheimer's disease. Here we ... More
The secretory granule protein syncollin binds to syntaxin in a Ca2(+)- sensitive manner.
AuthorsEdwardson JM, An S, Jahn R
JournalCell
PubMed ID9244306
The membrane proteins synaptobrevin, syntaxin, and SNAP-25 form the core of a ubiquitous fusion machine that interacts with the soluble proteins NSF and alpha-SNAP. During regulated exocytosis, membrane fusion is usually strictly controlled by Ca2+ ions. However, the mechanism by which Ca2+ regulates exocytosis is still unclear. Here we show ... More
Two active states of the Ras-related Bud1/Rsr1 protein bind to different effectors to determine yeast cell polarity.
AuthorsPark HO, Bi E, Pringle JR, Herskowitz I
JournalProc Natl Acad Sci U S A
PubMed ID9114012
Cells of budding yeast organize their cytoskeleton in a highly polarized manner during vegetative growth. Selection of a site for polarization requires a group of proteins including a Ras-like GTPase, Bud1, and its regulators. Another group of proteins, which includes a Rho-like GTPase (Cdc42), its guanine nucleotide exchange factor (Cdc24), ... More
Activities of human recombination protein Rad51.
AuthorsGupta RC, Bazemore LR, Golub EI, Radding CM
JournalProc Natl Acad Sci U S A
PubMed ID9012806
Homologous pairing and strand exchange, which are catalyzed by Escherichia coli RecA protein, are central to homologous recombination. Homologs of this protein are found in eukaryotes; however, little has been reported on the recombinase activities of the mammalian homologs, including the human protein, denoted HsRad51. For the studies described here, ... More
Staphylococcal enterotoxin D functions as a human B cell superantigen by rescuing VH4-expressing B cells from apoptosis.
Staphylococcal enterotoxins are potent superantigens, in that they activate T cells bearing specific V beta-chain gene segments. In this study, we analyzed the capacity of staphylococcal enterotoxin D (SED) to function as a B cell superantigen. SED induced T cell-dependent polyclonal proliferation and differentiation of B cells. In the absence ... More
REF2 encodes an RNA-binding protein directly involved in yeast mRNA 3'- end formation.
AuthorsRussnak R, Nehrke KW, Platt T
JournalMol Cell Biol
PubMed ID7862160
The Saccharomyces cerevisiae mutant ref2-1 (REF = RNA end formation) was originally identified by a genetic strategy predicted to detect decreases in the use of a CYC1 poly(A) site interposed within the intron of an ACT1-HIS4 fusion reporter gene. Direct RNA analysis now proves this effect and also demonstrates the ... More
Cloning and expression of a cDNA encoding epitopes shared by 15- and 60- kilodalton proteins of Cryptosporidium parvum sporozoites.
AuthorsJenkins MC, Fayer R, Tilley M, Upton SJ
JournalInfect Immun
PubMed ID7684726
A cDNA (CP15/60) encoding epitopes of Cryptosporidium parvum 15- and 60- kDa sporozoite proteins was isolated and expressed in Escherichia coli toward the goal of developing an immunogen for producing high-titer anticryptosporidial colostrum. Antisera prepared in rats to native C. parvum 15-kDa protein and used to identify the CP15/60 bacteriophage ... More
DREAM is a Ca2+-regulated transcriptional repressor.
AuthorsCarrion AM, Link WA, Ledo F, Mellstrom B, Naranjo JR
JournalNature
PubMed ID10078534
Fluxes in amounts of intracellular calcium ions are important determinants of gene expression. So far, Ca2+-regulated kinases and phosphatases have been implicated in changing the phosphorylation status of key transcription factors and thereby modulating their function. In addition, direct effectors of Ca2+-induced gene expression have been suggested to exist in ... More
Crx, a novel Otx-like paired-homeodomain protein, binds to and transactivates photoreceptor cell-specific genes.
AuthorsChen S, Wang QL, Nie Z, Sun H, Lennon G, Copeland NG, Gilbert DJ, Jenkins NA, Zack DJ
JournalNeuron
PubMed ID9390516
The otd/Otx gene family encodes paired-like homeodomain proteins that are involved in the regulation of anterior head structure and sensory organ development. Using the yeast one-hybrid screen with a bait containing the Ret 4 site from the bovine rhodopsin promoter, we have cloned a new member of the family, Crx ... More
Distinct HOX N-terminal arm residues are responsible for specificity of DNA recognition by HOX monomers and HOX.PBX heterodimers.
AuthorsPhelan ML, Featherstone MS
JournalJ Biol Chem
PubMed ID9079695
Dimerization with extradenticle or PBX homeoproteins dramatically improves DNA binding by HOX transcription factors, indicating that recognition by such complexes is important for HOX specificity. For HOX monomeric binding, a major determinant of specificity is the flexible N- terminal arm. It makes base-specific contacts via the minor groove, including one ... More
The RecD subunit of the RecBCD enzyme from Escherichia coli is a single- stranded DNA-dependent ATPase.
AuthorsChen HW, Ruan B, Yu M, Wang Jd, Julin DA
JournalJ Biol Chem
PubMed ID9092551
We have expressed the RecD subunit of the RecBCD enzyme from Escherichia coli as a fusion protein with a 31-amino acid NH2-terminal extension including 6 consecutive histidine residues (HisRecD). The overexpressed fusion protein can be purified in urea-denatured form by metal chelate affinity chromatography. The mixture of renatured HisRecD protein ... 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
The high affinity heparin-binding domain and the V region of fibronectin mediate invasion of human oral squamous cell carcinoma cells in vitro.
AuthorsKapila YL, Niu J, Johnson PW
JournalJ Biol Chem
PubMed ID9228073
Fibronectin is an extracellular matrix molecule composed of repeating subunits that create functional domains. These domains contain multiple binding sites for heparin and for various cell-surface receptors that modulate cell function. To examine the role that the high affinity heparin-binding region and the alternatively spliced V region of fibronectin play ... More
Cloning of Chinese hamster DNA topoisomerase I cDNA and identification of a single point mutation responsible for camptothecin resistance.
AuthorsTanizawa A, Beitrand R, Kohlhagen G, Tabuchi A, Jenkins J, Pommier Y
JournalJ Biol Chem
PubMed ID8244980
A camptothecin-resistant (DC3F/C-10) Chinese hamster cell line that contains a catalytically altered and camptothecin (CPT)-resistant DNA topoisomerase I (top 1) (Tanizawa, A., and Pommier, Y. (1992) Cancer Res. 52, 1848-1854) and the parent cell line (DC3F) were used to compare top 1 mRNAs and cDNAs. Northern blot analysis showed a ... More
Hsp105alpha suppresses the aggregation of truncated androgen receptor with expanded CAG repeats and cell toxicity.
AuthorsIshihara K, Yamagishi N, Saito Y, Adachi H, Kobayashi Y, Sobue G, Ohtsuka K, Hatayama T,
JournalJ Biol Chem
PubMed ID12714591
Spinal and bulbar muscular atrophy (SBMA) is a neurodegenerative disorder caused by the expansion of a polyglutamine tract in the androgen receptor (AR). The N-terminal fragment of AR containing the expanded polyglutamine tract aggregates in cytoplasm and/or in nucleus and induces cell death. Some chaperones such as Hsp40 and Hsp70 ... More
MICALs, a family of conserved flavoprotein oxidoreductases, function in plexin-mediated axonal repulsion.
Authors Terman Jonathan R; Mao Tianyi; Pasterkamp R Jeroen; Yu Hung-Hsiang; Kolodkin Alex L;
JournalCell
PubMed ID12110185
Members of the semaphorin family of secreted and transmembrane proteins utilize plexins as neuronal receptors to signal repulsive axon guidance. It remains unknown how plexin proteins are directly linked to the regulation of cytoskeletal dynamics. Here, we show that Drosophila MICAL, a large, multidomain, cytosolic protein expressed in axons, interacts ... More
Rab coupling protein (RCP), a novel Rab4 and Rab11 effector protein.
Authors Lindsay Andrew J; Hendrick Alan G; Cantalupo Giuseppina; Senic-Matuglia Francesca; Goud Bruno; Bucci Cecilia; McCaffrey Mary W;
JournalJ Biol Chem
PubMed ID11786538
Rab4 and Rab11 are small GTPases belonging to the Ras superfamily. They both function as regulators along the receptor recycling pathway. We have identified a novel 80-kDa protein that interacts specifically with the GTP-bound conformation of Rab4, and subsequent work has shown that it also interacts strongly with Rab11. We ... More
Trypanosoma cruzi expresses a plant-like ascorbate-dependent hemoperoxidase localized to the endoplasmic reticulum.
Authors Wilkinson Shane R; Obado Samson O; Mauricio Isabel L; Kelly John M;
JournalProc Natl Acad Sci U S A
PubMed ID12351682
In most aerobic organisms hemoperoxidases play a major role in H(2)O(2)-detoxification, but trypanosomatids have been reported to lack this activity. Here we describe the properties of an ascorbate-dependent hemoperoxidase (TcAPX) from the American trypanosome Trypanosoma cruzi. The activity of this plant-like enzyme can be linked to the reduction of the ... More
Interactions between mouse ZP2 glycoprotein and proacrosin; a mechanism for secondary binding of sperm to the zona pellucida during fertilization.
Authors Howes E; Pascall J C; Engel W; Jones R;
JournalJ Cell Sci
PubMed ID11739644
The mouse zona pellucida glycoprotein, mZP2, is thought to be the secondary receptor on eggs for retention of acrosome-reacted sperm during fertilization. Here, we present evidence that one of its complementary binding proteins on sperm is proacrosin/acrosin. mZP2 binds to proacrosin null sperm considerably less effectively than to wild-type sperm. ... More
The Trypanosoma cruzi Enzyme TcGPXI Is a Glycosomal Peroxidase and Can Be Linked to Trypanothione Reduction by Glutathione or Tryparedoxin.
Authors Wilkinson Shane R; Meyer David J; Taylor Martin C; Bromley Elizabeth V; Miles Michael A; Kelly John M;
JournalJ Biol Chem
PubMed ID11842085
Trypanosoma cruzi glutathione-dependent peroxidase I (TcGPXI) can reduce fatty acid, phospholipid, and short chain organic hydroperoxides utilizing a novel redox cycle in which enzyme activity is linked to the reduction of trypanothione, a parasite-specific thiol, by glutathione. Here we show that TcGPXI activity can also be linked to trypanothione reduction ... More
Activation mechanism of Gi and Go by reactive oxygen species.
Reactive oxygen species are proposed to work as intracellular mediators. One of their target proteins is the alpha subunit of heterotrimeric GTP-binding proteins (Galpha(i) and Galpha(o)), leading to activation. H(2)O(2) is one of the reactive oxygen species and activates purified Galpha(i2). However, the activation requires the presence of Fe(2+), suggesting ... More
Characterization of soluble forms of nonchimeric type V adenyl cyclase
AuthorsKlaus Scholich, Ann J. Barbier, Jason B. Mullenix, and Tarun B. Patel
JournalProc Natl Acad Sci U S A
PubMed ID9096321
Type V adenylyl cyclase (ACV) belongs to the family of Ca2+-inhibited cyclases. We have generated two soluble forms of the enzyme containing the C1 or C1a region (which lacks the C-terminal 112 amino acids) linked to the C2 domain and compared their regulation with the full-length ACV. All three forms ... More
Identification, molecular cloning, and characterization of a novel GABAA receptor-associated protein, GRIF-1.
AuthorsBeck M, Brickley K, Wilkinson HL, Sharma S, Smith M, Chazot PL, Pollard S, Stephenson FA.
JournalJ Biol Chem
PubMed ID12034717
A novel 913-amino acid protein, gamma-aminobutyric acid type A (GABA(A)) receptor interacting factor-1 (GRIF-1), has been cloned and identified as a GABA(A) receptor-associated protein by virtue of its specific interaction with the GABA(A) receptor beta 2 subunit intracellular loop in a yeast two-hybrid assay. GRIF-1 has no homology with proteins ... More
Spinesin/TMPRSS5, a novel transmembrane serine protease, cloned from human spinal cord.
A cDNA encoding a novel serine protease, which we designated spinesin, has been cloned from human spinal cord. The longest open reading frame was 457 amino acids. A homology search revealed that the human spinesin gene was located at chromosome 11q23 and contained 13 exons, the gene structure being similar ... More