Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.12 (PKG)
 2,515 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The phosphorylation of 40-S ribosomal subunits by cyclic-nucleotide-dependent and protease-activated protein kinases from rabbit reticulocytes was studied in vitro. Under optimal conditions the cAMP-dependent protein kinases incorporated up to 2 mol phosphate/mol S6. The electrophoretic mobility of S6 following phosphorylation indicated that this value was not an average for a population of maximally phosphorylated and non-phosphorylated S6 but represented a uniform population of diphosphorylated 40-S ribosomal subunits. Tryptic digests of S6 were analyzed by two-dimensional fingerprinting following phosphorylation with the cAMP-dependent protein kinase; two phosphopeptides, A and B, were observed. When 40-S ribosomal subunits were examined with the cGMP-dependent protein kinase, 1 mol phosphate was incorporated/mol S6. Upon analysis of the phosphopeptides obtained with the cGMP-dependent protein kinase, only peptide A was observed. S6 was also modified by a cyclic-nucleotide-independent protein kinase, protease-activated kinase II, following activation of the enzyme by limited proteolytic digestion. These findings suggest that a multiple protein kinase system may regulate the phosphorylation state of S6. A second ribosomal protein, S10, was phosphorylated by a different cyclic-nucleotide-independent protein kinase, protease-activated kinase I, and up to 1 mol phosphate was incorporated.
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PMID:Phosphorylation of 40-S ribosomal subunits by cAMP-dependent, cGMP-dependent and protease-activated protein kinases. 628 Oct 8

Lactogens [prolactin (Prl) and growth hormone] stimulate phosphorylation of the 40S ribosomal protein, S6, in Nb2 cells by mechanisms that do not involve participation of cAMP or protein kinase A, protein kinase C, or cGMP-dependent protein kinase. However, inhibition of tyrosine kinase (TK) abrogates Prl-mediated macromolecular biosynthesis. Inasmuch as lactogen signaling may involve sequential activation of protein kinases, the effect of Prl on the well-characterized mitogen-activated protein kinase (MAPK) and S6 kinase (S6K), the enzyme responsible for S6 phosphorylation in vivo, and their relationship to Nb2 macromolecular biosynthesis and mitogenesis were investigated. The results show that MAPK stimulation is transient (peak activity, 30 min) and precedes that of S6K, which reaches a maximum at 1.5-2 h, and slowly returns towards control levels at 6 h. Both staurosporine which inhibits GH receptor-associated kinase (JAK2) and genistein (GEN), an inhibitor of membrane-associated and cytoplasmic TKs, abrogate Prl-stimulated TK, MAPK, and S6K. Rapamycin (RAP), a specific inhibitor of p70S6K, completely blocks S6K but does not affect TK and MAPK. TK and MAPK activity correlates with Prl-stimulated anabolism, i.e., protein and DNA synthesis and mitogenesis. Thus, concentrations of STR and GEN which abrogate TK and MAPK inhibit anabolism virtually 100%. However, RAP, which inhibits S6K (ca. 100%) but not TK or MAPK, only delays Prl-mediated anabolism. These results indicate that Prl signaling in Nb2 cells involves a protein kinase cascade and that regulation of receptor-associated kinase, TK, and MAPK correlates with anabolism. The role of S6K (and S6 phosphorylation) appears to be ancillary.
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PMID:Stimulation of receptor-associated kinase, tyrosine kinase, and MAP kinase is required for prolactin-mediated macromolecular biosynthesis and mitogenesis in Nb2 lymphoma. 784 Jun 14

RPS19 is a component of the 40S small ribosomal subunit encoded by RPS19 gene. The cDNA of RPS19 was cloned successfully for the first time from the Giant Panda using RT-PCR technology. It was also sequenced, analyzed preliminarily, and expressed in Escherichia coli. The length of cDNA fragment cloned is 469 bp, and it contains an open-reading frame of 438 bp encoding 145 amino acids. Alignment analysis indicates that the nucleotide sequence and the deduced amino acid sequence share a high homology with those of Homo sapiens, Mus musculus, and Rattus norvegicus by 95.89%, 92.47%, and 93.61%, and 100.00%, 99.31%, and 99.31%, respectively. Topology prediction shows that there is one cAMP- and cGMP-dependent protein kinase phosphorylation site, four protein kinase C phosphorylation sites, one casein kinase II phosphorylation site, one tyrosine kinase phosphorylation site, three N-myristoylation sites, one amidation site, and one ribosomal protein S19e signature in the RPS19 protein of the Giant Panda (Ailuropoda melanoleuca). The RPS19 gene was overexpressed in E. coli and expression confirmed by western blotting. The results indicated that the RPS19 gene can be readily expressed in E. coli, and the N-terminally GST-tagged protein was a 42 kDa polypeptide, in good agreement with the predicted molecular weight. The protein obtained could be purified and its function studied.
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PMID:cDNA cloning and overexpression of ribosomal protein S19 gene (RPS19) from the Giant Panda. 1907 23