摘要：

为进一步探究水稻多胚候选基因OsPE的生物学功能,以粳稻品种日本晴和籼稻品种巴斯马蒂370为研究材料,选取正常生长条件下供试材料的成熟叶片,综合运用生物信息学、RT-PCR、TA克隆、半定量及qPCR等技术鉴定并分析水稻多胚候选基因OsPE的可变剪接体。结果表明,虽然生物信息学分析显示OsPE基因在粳稻中存在3种可变剪接体,在籼稻中无可变剪接体,但通过特异引物进行RT-PCR扩增,结合TA克隆及测序验证,在粳稻品种日本晴中鉴定到了OsPE基因3种可变剪接体的真实存在;在籼稻品种巴斯马蒂370中鉴定到2种新的可变剪接体。同时,半定量及qPCR结果显示:正常生长条件下,供试材料成熟叶片中OsPE基因可变剪接体存在表达差异,依次为OsPEc>OsPEa>OsPEb,且该基因在不同水稻品种中存在相同的表达趋势。最后,水稻OsPE基因编码蛋白进化分析及功能预测分析结果显示:OsPE蛋白在禾本科,尤其是稻属中高度保守(蛋白序列一致性普遍高于99%),有待于进一步研究该基因是否参与调控水稻抗逆响应、细胞分裂及细胞凋亡等生物学功能,而不是调控水稻多胚产生。综上所述,OsPE基因在禾本科,尤其是稻属中高度保守,该基因在粳稻和籼稻中可能有着相同的剪接模式,其可变剪接体在正常生长条件下存在表达差异,但表达趋势相同,OsPEc剪接体在OsPE基因功能发挥中占主导,有待于进一步研究该基因是否参与调控水稻抗逆响应、细胞分裂及细胞凋亡等生物学功能,而不是调控水稻多胚产生。

关键词: 水稻, 多胚候选基因, OsPE, 可变剪接体

Abstract:

To further explore the biological function of rice polyembryo candidate gene OsPE,Oryza sativa ssp.Japonica cv.Nipponbare and Indica cv.Basmati 370 was taken as the research materials, and the mature leaves of the test materials under normal growth conditions were employed.Bioinformatics,RT-PCR,TA cloning,semi-quantitative,and qPCR were used to identify and analyze the splicers of OsPE.The bioinformatics analysis showed three kinds of variable splices of OsPE in Japonica rice and no variable splices in Indica rice.But the existence of three variable splices of the OsPE gene was identified in Japonica rice.Two new variable splice variants were found in Indica rice through RT-PCR amplification with specific primers,combined with TA cloning and sequencing verification.Subsequently,the semi-quantitative and qPCR results showed differences in the expression of the variable splices of the OsPE gene.Moreover,the expression intensities are as follows:OsPEc>OsPEa>OsPEb,the gene had the same expression trend in different rice varieties.Finally,the evolutionary analysis and functional prediction of the protein encoded by the OsPE gene showed that the OsPE protein was highly conserved in Gramineae,especially in Oryza L.(percent identity was higher than 99%).It needs to be further studied whether this gene was involved in regulating rice's stress response,cell division,and apoptosis but not the regulation of rice polyembryony production.To sum up,the OsPE gene was highly conserved in Gramineae,especially in Oryza L..This gene had the same splicing pattern in Japonica and Indica rice.Its variable splices had different expressions under normal growth conditions,but the expression trend was the same,OsPEc spliceosome dominate the function of the OsPE gene.It needed to be further studied whether this gene was involved in regulating rice's stress response,cell division,and apoptosis but not the regulation of rice polyembryony production.

Key words: Rice, Polyembryo candidate gene, OsPE, Splice variants