一个特异水稻原纤蛋白FBN11的生物信息学和基因表达特性分析

Fibrillin 11(FBN 11)是植物质体中FBN蛋白家族的重要成员之一,比其他成员多300~500个氨基酸残基,说明其可能存在某些特异性结构和功能。本研究在水稻幼苗中扩增获得到了一个受非生物逆境胁迫诱导的OsFBN11基因的全长cDNA,该基因含有12个内含子和13个外显子。其编码蛋白的分子量为72.36 kD,pI值为9.26。生物信息学分析结果表明,该蛋白含有无规则卷曲、α螺旋和β-折叠3种氨基酸二级结构,不含有跨膜结构域,蛋白亲水性强,PSORT软件预测该蛋白可能定位于叶绿体中。进一步对14种植物FBN11蛋白的同源性和5个物种该蛋白的保守结构域分析,发现该蛋白兼有典型的PAP-Fibrillin结构域和蛋白激酶PKc结构域。水稻全生育期芯片分析显示该基因主要在愈伤组织、叶片和根系中高水平表达。RT-PCR检测结果显示,该基因在水稻幼苗中受ABA、NaCl和干旱胁迫处理上调表达。上述结果表明,OsFBN11可能在水稻质体发育和抗非生物胁迫反应中发挥重要作用。

Bioinformatics and Expression Analysis of a Specific Fibrillin Gene FBN11 in Rice

FBN 11 gene, a member of fibrillin gene family, is one of the important members of the FBN family of proteins in plastids of plants. It has the 300-500 amino acid residues longer than do other members in this family, suggesting its specific functions in higher plants. In this study, the full-length cDNA of a OsFBN11 gene regulated by abiotic stresses in rice seedlings was cloned and analyzed, it was found to contain 12 introns and 13 exons, and can encode a protein with M.W. 72.4 kDa, the pI value 9.3. Bioinformatics analysis showed that, this protein contains a random-coil, alpha helix and extended strand, does not contain a transmembrane domain, and is also highly hydrophilic. PSORT software predicted this protein may be localized in chloroplast. Analyses of FBN11 protein homologies in 14 plant species and conserved domains in 5 plant species showed that, this protein has a typical PAP-Fibrillin domain and PKc kinase domain. The whole growth period rice chip analysis showed that OsFBN11 gene is highly expressed in callus, leaves and root tissues. RT-PCR detection showed that OsFBN11 gene expressions were induced by ABA, NaCl and drought stress treatments in rice seedlings. These results above show that OsFBN11 plays an important role in the response to plastid development and abiotic stress in rice.