Role of tyrosine kinase Jak2 in prolactin-induced differentiation and growth of mammary epithelial cells.
AuthorsXie Jianwu; LeBaron Matthew J; Nevalainen Marja T; Rui Hallgeir;
JournalJ Biol Chem
PubMed ID11821424
Genetic studies in mice have established a critical role for prolactin receptors and transcription factor Stat5 in mammary gland differentiation. However, the enzymatic coupling between prolactin receptors and Stat5 in this process has not been established. In addition to Jak2, several other tyrosine kinases reportedly also are associated with prolactin ... More
MdmX binding to ARF affects Mdm2 protein stability and p53 transactivation.
Authors Jackson M W; Lindstrom M S; Berberich S J;
JournalJ Biol Chem
PubMed ID11297540
'Regulation of p53 involves a complex network of protein interactions. The primary regulator of p53 protein stability is the Mdm2 protein. ARF and MdmX are two proteins that have recently been shown to inhibit Mdm2-mediated degradation of p53 via distinct associations with Mdm2. We demonstrate here that ARF is capable ... More
Silencing of Transcription of the Human Luteinizing Hormone Receptor Gene by Histone Deacetylase-mSin3A Complex.
Authors Zhang Ying; Dufau Maria L;
JournalJ Biol Chem
PubMed ID12091390
'Modification of chromatin structure by histone acetylases and deacetylases is an important mechanism in modulation of eukaryotic gene transcription. The present study investigated regulation of the human luteinizing hormone receptor (hLHR) gene by histone deacetylases. Inhibition of histone deacetylases (HDACs) by trichostatin A (TSA) increased hLHR promoter activity by 40-fold ... More
Membrane targeting of ATP-sensitive potassium channel. Effects of glycosylation on surface expression.
Authors Conti Lisa R; Radeke Carolyn M; Vandenberg Carol A;
JournalJ Biol Chem
PubMed ID11994306
'Oligosaccharides play significant roles in trafficking, folding, and sorting of membrane proteins. Sulfonylurea receptors (SURx), members of the ATP binding cassette family of proteins, associate with the inward rectifier Kir6.x to form ATP-sensitive potassium channels (K(ATP)). These channels are found on the plasma membrane in many tissues and play a ... More
Functional Characterization of the G Protein Regulator RGS13.
Authors Johnson Eric N; Druey Kirk M;
JournalJ Biol Chem
PubMed ID11875076
'The signaling cascades evoked by G protein-coupled receptors are a predominant mechanism of cellular communication. The regulators of G protein signaling (RGS) comprise a family of proteins that attenuate G protein-mediated signal transduction. Here we report the characterization of RGS13, the smallest member of the RGS family, which has been ... More
Chimaerins, novel non-protein kinase C phorbol ester receptors, associate with Tmp21-I (p23): evidence for a novel anchoring mechanism involving the chimaerin C1 domain.
Authors Wang HongBin; Kazanietz Marcelo G;
JournalJ Biol Chem
PubMed ID11689559
The regulation and function of chimaerins, a family of
myc boxes, which are conserved in myc family proteins, are signals for protein degradation via the proteasome.
AuthorsFlinn EM, Busch CM, Wright AP
JournalMol Cell Biol
PubMed ID9742113
Cellular levels of the rapidly degraded c-myc protein play an important role in determining the proliferation status of cells. Increased levels of c-myc are frequently associated with rapidly proliferating tumor cells. We show here that myc boxes I and II, found in the N termini of all members of the ... More
Construction and characterization of a monomeric insulin receptor.
Authors Wu James Jianping; Guidotti Guido;
JournalJ Biol Chem
PubMed ID12023954
A mutant insulin receptor was constructed by replacing cysteine residues Cys(524), Cys(682), Cys(683), and Cys(685) with serine. The mutant was expressed in COS7 and Chinese hamster ovary cells, did not form covalently linked dimers, and was present at the cell surface. There was half as much insulin binding activity at ... More
A novel human striated muscle RING zinc finger protein, SMRZ, interacts with SMT3b via its RING domain.
Authors Dai K S; Liew C C;
JournalJ Biol Chem
PubMed ID11283016
The RING domain is a conserved zinc finger motif, which serves as a protein-protein interaction interface. Searches of a human heart expressed sequence tag data base for genes encoding the RING domain identified a novel cDNA, named striated muscle RING zinc finger protein (SMRZ). The SMRZ cDNA is 1.9 kilobase ... More
Authors Kraus Richard J; Ariazi Eric A; Farrell Michael L; Mertz Janet E;
JournalJ Biol Chem
PubMed ID11986328
The estrogen-related receptor alpha (ERRalpha) is an orphan member of the nuclear receptor superfamily. We show that the major isoform of the human ERRalpha gene, ERRalpha1, can sequence-specifically bind a consensus palindromic estrogen response element (ERE) and directly compete with estrogen receptor alpha (ERalpha) for binding. ERRalpha1 activates or represses ... More
Regulation of insulin-like growth factor I receptor dephosphorylation by SHPS-1 and the tyrosine phosphatase SHP-2.
Authors Maile Laura A; Clemmons David R;
JournalJ Biol Chem
PubMed ID11779860
Activation of insulin-like growth factor I receptor (IGF-IR) kinase is an important site of control of IGF-I-linked intracellular signaling pathways. One potentially important regulatory variable is IGF-IR dephosphorylation. It has been shown that SHP-2, a tyrosine phosphatase, can bind to the activated IGF-IR in vitro; however, its role in IGF-IR ... More
Structural requirements for the recruitment of Gaa1 into a functional glycosylphosphatidylinositol transamidase complex.
Glycosylphosphatidylinositol (GPI)-anchored proteins are synthesized on membrane-bound ribosomes, translocated across the endoplasmic reticulum membrane, and GPI-anchored by GPI transamidase (GPIT). GPIT is a minimally heterotetrameric membrane protein complex composed of Gaa1, Gpi8, PIG-S and PIG-T. We describe structure-function analyses of Gaa1, the most hydrophobic of the GPIT subunits, with the ... More
Plasminogen activator inhibitor-1 (PAI-1) is an important regulator of fibrinolysis by its inhibition of both tissue-type and urokinase plasminogen activators. PAI-1 levels are elevated in type II diabetes and this elevation correlates with macro- and microvascular complications of diabetes. Insulin increases PAI-1 production in several experimental systems, but the mechanism ... More
EMR4, a Novel Epidermal Growth Factor (EGF)-TM7 Molecule Up-regulated in Activated Mouse Macrophages, Binds to a Putative Cellular Ligand on B Lymphoma Cell Line A20.
Authors Stacey Martin; Chang Gin-Wen; Sanos Stephanie L; Chittenden Laura R; Stubbs Lisa; Gordon Siamon; Lin Hsi-Hsien;
JournalJ Biol Chem
PubMed ID12023293
A novel member of the EGF-TM7 family, mEMR4, was identified and characterized. The full-length mouse EMR4 cDNA encodes a predicted 689-amino acid protein containing two epidermal growth factor (EGF)-like modules, a mucin-like spacer domain, and a seven-transmembrane domain with a cytoplasmic tail. Genetic mapping established that mEMR4 is localized in ... More