A protein kinase Cdelta-binding protein SRBC whose expression is induced by serum starvation.
West-Western screening of a cDNA expression library using 32P-labeled, autophosphorylated protein kinase Cdelta (PKCdelta) as a probe, led us to identify cDNA clones encoding a PKCdelta-binding protein that contains a leucine zipper-like motif in its N-terminal region and two PEST sequences in its C-terminal region. This protein shows overall sequence similarity (43.3%) to the serum deprivation response (sdr) gene product, and we named it SRBC (sdr-related gene product that binds to c-kinase). PKCdelta binds to the C-terminal half of SRBC through the regulatory domain and phosphorylates it in vitro. In COS1 cells, the phosphorylation of over-expressed SRBC is stimulated by 12-O-tetradecanoylphorbol-13-acetate and further enhanced by the over-expression of PKCdelta. The mRNA for SRBC is detected in a wide variety of cultured cell lines and tissues and is strongly induced by serum starvation. Furthermore, SRBC mRNA is induced during retinoic acid-induced differentiation of P19 cells. These results suggest that SRBC serves as a substrate and/or receptor for PKC and might be involved in the control of cell growth mediated by PKC.
Izumi
Y
Y
Department of Molecular Biology, Yokohama City University School of Medicine, 3-9, Fuku-ura, Kanazawa-ku, Yokohama 236, Japan.
Hirai
S i
Si
Tamai
Y
Y
Fujise-Matsuoka
A
A
Nishimura
Y
Y
Ohno
S
S
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D051745:Protein Kinase C-delta; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D002352:Carrier Proteins; C105104:Cavin3 protein, rat; D018076:DNA, Complementary; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes; D018160:Receptors, Cytoplasmic and Nuclear; C497259:Prkcd protein, mouse; D011493:Protein Kinase C; D051745:Protein Kinase C-delta