高粱CRY2基因的克隆及其表达分析

从高粱(Sorghum bicolor L．var．R111)幼苗中提取总RNA，利用RT-PCR和cDNA的3′末端的快速扩增方法(3′RACE)，第一次克隆了高粱隐花色素2基因(CRY2)的cDNA序列。该序列包括了一个完整的开放阅读框，编码大小为690个氨基酸残基的蛋白质，与水稻、番茄和拟南芥CRY2蛋白质的同源性分别为87％、57％和45．5％。高粱CRY2基因组DNA含有3个内含子和4个外显子。RT-PCR检测结果表明，高粱CRY2基因在根、茎和叶中都有转录。Western blotting结果显示CRY2蛋白在根、茎和叶中表达，并在黑暗中积累，蓝光下降解。高粱CRY2可能在蓝光诱导的幼苗去黄化反应中起作用。

Cloning and Expression Analysis of CRY2 Gene in Sorghum bicolor

CRY2 is the apoprotein of cryptochrome 2and CRY2 cDNA has been cloned from Sorghum bi-color in this study. The results of sequence analysisshows that it contains a complete open reading frameencoding a predicted protein of 690 amino acids shar-ing 87% identity with the CRY2 of rice, but only45.5% with that of Arabidopsis and 57% with that oftomato. The DNA sequence of sorghum CRY2 con-tains three introns and four exons. RT-PCR resultsshow that CRY2 has been transcribed in root, leaf andmesocotyl in sorghum seedlings. CRY2 protein hasbeen shown by Western blot analysis to be present inmesocotyl, leaf and root, and to be accumulated in thedark and to be degraded under blue light.