Guo X L, Bai L R, Su C Q, Shi L R, Wang D W
College of Biological Science, Hengshui University, Hengshui, China.
Genet Mol Res. 2013 Dec 19;12(4):6860-70. doi: 10.4238/2013.December.19.5.
A drought-induced gene, DIP3, encoding a chitinase III protein was isolated from the roots of upland rice by reverse transcription-polymerase chain reaction (RT-PCR). Sequence analysis demonstrated that the cDNA and deduced protein showed high identity to Oryza sativa class III chitinase. The deduced protein contained a signal peptide sequence in the N-terminal region of 21aa and a conserved glycosyl hydrolase (GH) 18 domain. The secondary and 3D structures were analyzed and showed that it contained α-helix, β-sheets, extended strand and random coil structures and that it was approximately spheroidal. Real-time quantitative PCR analysis revealed that expression levels accumulated rapidly under different forms of abiotic stress (drought, salt and low temperature), peaked at different times and then decreased. These results implied that as a member of class III chitinases, DIP3 may function as a stress-induced protein involved in the regulation of plant stress response.
通过逆转录-聚合酶链反应(RT-PCR)从旱稻根部分离出一个干旱诱导基因DIP3,其编码一种几丁质酶III蛋白。序列分析表明,该cDNA及其推导的蛋白质与水稻III类几丁质酶具有高度同源性。推导的蛋白质在N端区域含有一个21个氨基酸的信号肽序列和一个保守的糖基水解酶(GH)18结构域。对其二级结构和三维结构进行分析,结果显示它含有α-螺旋、β-折叠、延伸链和无规卷曲结构,且大致呈球形。实时定量PCR分析表明,在不同形式的非生物胁迫(干旱、盐和低温)下,其表达水平迅速积累,在不同时间达到峰值,然后下降。这些结果表明,作为III类几丁质酶的一员,DIP3可能作为一种胁迫诱导蛋白参与植物胁迫反应的调控。