PCR法检测水稻中存在Ras类蛋白基因家族(简报)

IDENTIFICATION OF RAS-RELATED PROTEIN GENE FAMILY IN RICE BY PCR

Ras类蛋白家族是普遍存在于动物及低等真核生物细胞中的一类单亚基GTP结合蛋白(20—29kDa),它们在一系列细胞过程中起重要作用。它们有GTP结合蛋白共有的作用机制。在刺激物诱导下,结合GTP成为活化状态,与效应子作用产生一定效应;GTP水解成GDP后恢复GDP结合状态,即非活化状态。它们通过GTPase驱动的构象变化的循环,作为“分子开关”起调控作用。目前已有40多种Ras类蛋白被发现,按结构可分为Ras、

Here we report the identification of Ras-related protein gene family in rice. Two fully degenerated oligonucleotide primers corresponding to two conserved motifs (WDTAGQE & VGNKCDL) in Ras-related proteins were used in RT-PCR (reverse trancription-polymerase chain reaction) to amplify rice cDNA. Six different cDNA fragments (riR 1 to riR6) have been cloned, whose deduced amino acid sequences exhibit high homology to the Ypt/Rab subfamily in Ras-related proteins. RiR1, RiR 3 and RiR 4 show more than 90% homology to Zea mays YPTm proteins; RiR 2 display 90% identity to Dic-tyostelium discoideum sasl protein; RiR 5 display 78% identity to Schizosaccharomy-ces pombe YPT 3 protein. RiR 6 is 82% identical to mammalian rabll protein. Our results suggest that there is great complexity in Ras-related protein family in plants and they may play important roles in the signal transduction of growth and development.