p21ras farnesyltransferase alpha- and beta-subunits are phosphorylated in PC-12 cells: TGF-beta signaling pathway independent phosphorylation.
Farnesyltransferase (FTase) catalyzes the transfer of a farnesyl isoprenoid to the conserved carboxyl-terminal cysteine residue of proteins terminating with the CAAX sequence. Rat brain FTase is a heterodimer consisting of a 49 kDa alpha-subunit and a 46 kDa beta-subunit. In this report, we show, for the first time, that the beta-subunit of FTase is phosphorylated in vivo and the FTase heterodimer contains phosphorylated alpha/beta-subunits in rat adrenal medulla pheocytochroma PC-12 cells. The presence of the phosphorylated FTase subunits as heterodimer in PC-12 cells which are known to be deficient in TGF-beta signaling pathways argues against the involvement of this pathway in their phosphorylation and heterodimerization.
Kumar
A
A
Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, College of Medicine, Little Rock 72205, USA.
Mehta
K D
KD
D019883:Alkyl and Aryl Transferases / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D004306:Dose-Response Relationship, Immunologic; D016716:PC12 Cells; D010766:Phosphorylation; D011233:Precipitin Tests; D051381:Rats; D015398:Signal Transduction / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000172:deficiency
D016212:Transforming Growth Factor beta; D019883:Alkyl and Aryl Transferases; C064911:p21(ras) farnesyl-protein transferase