The Ser/Thr phosphorylation of insulin receptor substrate 1 (IRS) is one key mechanism to stimulate and/or attenuate insulin signal transduction. Using a phospho-specific polyclonal antibody directed against phosphorylated Ser(318) of IRS-1, we found a rapid and transient insulin-stimulated phosphorylation of Ser(318) in human and rodent skeletal muscle cell models and in muscle tissue of insul...

Previous studies indicated that treatment of cells with 12-O-tetradecanoylphorbol-13-acetate induced phosphorylation of Ser-985 at the juxtamembrane of c-Met, the receptor tyrosine kinase for hepatocyte growth factor (HGF), and this was associated with decreased tyrosine phosphorylation of c-Met. However, the regulatory mechanisms and the biological significance of the Ser-985 phosphorylation i...

Specific sites in the linker region of human P-glycoprotein phosphorylated by protein kinase C (PKC) were identified by means of a synthetic peptide substrate, PG-2, corresponding to residues 656-689 from this region of the molecule. As PG-2 has several sequences of the type recognized by the cyclic AMP-dependent protein kinase (PKA), PG-2 was also tested as a substrate for PKA. PG-2 was phosph...

Serotonin (5-hydroxytryptamine: 5HT) is an important neuroactive substance in the model roundworm, Caenorhabditis elegans. Aside from having effects in feeding and egg-laying, 5HT inhibits motility and also modulates several locomotory behaviors, notably food-induced slowing and foraging. Recent evidence showed that a serotonergic 5HT2-like receptor named SER-1 (also known as 5HT2ce) was respon...

PURPOSE The purpose of this research was to determine whether estrogen receptor alpha specifically phosphorylated at Ser(118) is associated with clinical outcome in primary breast tumors from estrogen receptor-positive and node-negative breast cancer patients. EXPERIMENTAL DESIGN Estrogen receptor alpha specifically phosphorylated at Ser(118) was determined by immunohistochemistry in 117 prim...

Hormone-sensitive lipase (HSL) is important for the degradation of triacylglycerol in adipose and muscle tissue, but the tissue-specific regulation of this enzyme is not fully understood. We investigated the effects of adrenergic stimulation and AMPK activation in vitro and in circumstances where AMPK activity and catecholamines are physiologically elevated in humans in vivo (during physical ex...

To directly compare clinical side effects and biological response modification, IFN-beta ser, IFN-gamma, or the combination of IFN-beta ser plus IFN-gamma was administered to 21 cancer patients. Each IFN or the combination was given intravenously on days 1, 8, and 15 in varied order. Each IFN and the combination resulted in significant (P less than 0.05) modulation of IFN-induced proteins. IFN-...

A synthetic pentadecapeptide, Pro-Leu-Ser-Arg-Thr-Leu-Ser-Val-Ser-Ser-Leu-Pro-Gly-Leu-Glu, corresponding to the phosphorylatable site at the NH2 terminus of glycogen synthase, could be phosphorylated stoichiometrically at seryl residue 7 by both phosphorylase kinase and cAMP-dependent protein kinase. Phosphorylation of seryl residue 3 also occurred after prolonged incubation with cAMP-dependent...

The substrate specificity of protein kinase C was studied and compared with that of cyclic AMP-dependent protein kinase (protein kinase A) by using bovine brain myelin basic protein as a model substrate. This basic protein was phosphorylated at multiple sites by both of these protein kinases. In this analysis, the basic protein was thoroughly phosphorylated in vitro with [gamma-32P]ATP and each...

We describe a novel experimental system in mice for the study of ovarian autoimmune disease, a condition encountered in women with premature ovarian failure. The ovarian autoimmune disease is induced in B6AF1 mice by a 15-amino acid peptide (Cys-Ser-Asn-Ser-Ser-Ser-Ser-Gln-Phe-Gln-Ile-His-Gly-Pro-Arg) from mouse ZP3, the sperm-binding component of the zona pellucida that surrounds growing and m...