Cyclin-dependent kinases (CDKs) are a family of protein kinases first discovered for their role in regulating the cell cycle. They are also involved in regulating transcription, mRNA processing, and the differentiation of nerve cells. [1] They are present in all known eukaryotes and their regulatory function in the cell cycle has been evolutionarily conserved. In fact, yeast cells can proliferate normally when their CDK gene has been replaced with the homologous human gene. [1] [2] CDKs are relatively small proteins, with molecular weights ranging from 34 to 40 kDa, and contain little more than the kinase domain. [1] By definition, a CDK binds a regulatory protein called a cyclin. Without cyclin, CDK has little kinase activity; only the cyclin-CDK complex is an active kinase. CDKs phosphorylate their substrates on serines and threonines, so they are serine-threonine kinases.[1] The consensus sequence for the phosphorylation site in the amino acid sequence of a CDK substrate is [S/T*]PX[K/R], where S/T* is the phosphorylated serine or threonine, P is proline, X is any amino acid, K is lysine, and R is arginine [1] + _ M. R+ | F" A2 d) Q; j7 I多谢啦作者: iseeyou1210 时间: 2010-12-31 21:54
就是CDK的target位点比较保守就是了,常见的是motif是有4个氨基酸做成的, 第一个氨基酸必须是丝氨酸或者苏氨酸,第二个位点是proline (脯氨酸),第三位是任何一个氨基酸, 第四位是赖氨酸或者精氨酸. 0 u0 P4 f. n# \: z