PROTEIN-KINASE C-DELTA ACCEPTS GTP FOR AUTOPHOSPHORYLATION
PROTEIN-KINASE C-DELTA ACCEPTS GTP FOR AUTOPHOSPHORYLATION
复制标题
DOI：
10.1006/bbrc.1995.1087
复制
发表时间：
1995-01-17
影响因子：
3.1
通讯作者：
MARKS, F
中科院分区：
文献类型：
--
作者：
GSCHWENDT, M;KITTSTEIN, W;MARKS, F
来自猪脾脏的蛋白激酶C δ（PKC δ）具有显著的自磷酸化能力。在GTP存在的情况下，自磷酸化比ATP更有效（6倍）。将15 mol磷酸/mol酶与作为磷酸供体的GTP结合。PKC delta与ATP的自磷酸化活性约为同工酶α、β、γ（cPKC）的4倍，而与GTP的自磷酸化活性约为cPKC的24倍。蛋白激酶A和酪氨酸激酶src的催化亚基在GTP存在下不自磷酸化或仅轻微自磷酸化。PKC δ与GTP的自磷酸化与ATP的自磷酸化在以下方面没有不同：TPA或苔藓抑素对其的激活、星形孢菌素对其的抑制、磷酸化氨基酸（丝氨酸和苏氨酸）的类型和反应模式（肽内反应）。然而，不同的位点被GTP和ATP磷酸化，如通过掺入的磷酸盐的量和磷酸肽图谱所示。(C)出版社：Academic Press
Protein kinase C delta (PKC delta) from porcine spleen exhibits a marked capacity for autophosphorylation. Autophosphorylation is much more efficient in the presence of GTP than of ATP (6-fold). 15 mol phosphate/mol enzyme is incorporated with GTP as phosphate donor. The activity of PKC delta for autophosphorylation with ATP is around 4 times that of the isoenzymes alpha,beta,gamma (cPKC), and with GTP it is around 24 times that of cPKC. The catalytic subunit of protein kinase A and the tyrosine kinase src are not or only slightly autophosphorylated in the presence of GTP. The autophosphorylation of PKC delta with GTP does not differ from that with ATP regarding its activation by TPA or bryostatin, its inhibition by staurosporine, the type of phosphorylated amino acids (serine and threonine) and the mode of reaction (intrapeptide reaction). However, different sites are phosphorylated with GTP and ATP, as indicated by the amount of phosphate incorporated and by phosphopeptide mapping. (C) 1995 Academic Press, Inc.