Selective enhanced phosphorylation of shrimp beta-tubulin by PKC-delta with PEP(taxol), a synthetic peptide encoding the taxol binding region.
Beta-tubulin cDNA from the shrimp Penaeus japonicus was isolated by homology cloning. Expression of cDNA in Escherichia coli yielded a 55 kDa polypeptide, positive for monoclonal antibodies against mammalian beta-tubulin. Autoradiography demonstrated the bacterially expressed hepatopancreas beta-tubulin of P. japonicus is specifically phosphorylated by the delta isoenzyme of protein kinase C (PKC-delta) purified from the plasma membrane of the shrimp heart, in the presence of the receptor for activated PKC (RACK), but not in its absence. Purified shrimp heart PKC-delta is able to phosphorylate bacterially expressed shrimp beta-tubulin without the presence of Ca(++), but requires Mg(++). The kinase activity of purified PKC-delta on bacterially expressed beta-tubulin was enhanced by incubation with PEP(taxol), a synthetic peptide encoding the taxol-binding region of beta-tubulin. In other words, PEP(taxol) modulates the kinase activity of PKC-delta through RACK.
Chen
Wen-Yi
WY
Division of Biochemistry and Molecular Science, Institute of Zoology, Academia Sinica, Nankang, Taipei 11529, Taiwan.
Yang
Yu-Ming
YM
Chuang
Nin-Nin
NN
D000595:Amino Acid Sequence; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000493:pharmacokinetics; D001483:Base Sequence; D001665:Binding Sites; D015153:Blotting, Western; D018076:DNA, Complementary / Q000235:genetics; D033364:Decapoda / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D005786:Gene Expression Regulation; D007527:Isoenzymes / Q000378:metabolism*; D008969:Molecular Sequence Data; D009206:Myocardium / Q000201:enzymology; D017239:Paclitaxel / Q000493:pharmacokinetics; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D051745:Protein Kinase C-delta; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface / Q000378:metabolism*; D014404:Tubulin / Q000378:metabolism*
D000972:Antineoplastic Agents, Phytogenic; D018076:DNA, Complementary; D007527:Isoenzymes; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface; D014404:Tubulin; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; D017239:Paclitaxel