性别决定基因TASSELSEED2在水稻中的功能歧化性浅析

发布时间：2018-04-27 08:47

本文选题：水稻 + 玉米　；参考：《华北农学报》2017年03期

【摘要】：花器官的发育不仅影响农作物的生产,通过性别决定产生单性花的机制亦是重要的基础理论问题。TASSELSEED2基因是与JA合成有关的调控玉米单性雄花产生的性别决定基因,对一些植物中TS2同源基因的表达分析表明TS2蛋白可能在进化过程中产生了功能歧化。为探究TS2蛋白在进化过程中其功能是否发生了歧化,首先通过生物信息学手段对水稻和玉米的TS2基因进行了比较分析,分子进化分析表明,TS2基因在一些植物中可能并不仅仅局限于抑制雌蕊发育的性别决定功能。因此,猜测两性花植物水稻中的TS2可能具有其他功能。利用蛋白质三维结构预测软件,发现水稻TS2基因编码典型的SDR蛋白,含有保守的GASGIG和YTASK基序,其作用底物可能与玉米TS2蛋白类似。启动子分析表明OsTS2和玉米TS2的激素应答元件存在差别。随后,利用RNA-seq数据进行了OsTS2与玉米TS2的组织器官表达分析,并利用实时荧光定量技术考察外源Me JA喷施处理对OsTS2与玉米TS2基因表达的影响。结果表明,OsTS2主要在花序中表达,经外源MeJA处理后其表达量明显升高;而玉米TS2在雄穗分化关键期的叶片中表达量最高,其表达量基本不受外源Me JA影响。OsTS2与玉米TS2表达方面的差异提示水稻TS2可能具有与玉米TS2不同的功能,为深入了解TS2在两性花植物中的功能提供了线索。
[Abstract]:The development of floral organs not only affects the production of crops, but also the mechanism of producing unisexual flowers through sex determination. TASSELSEED2 gene is a sex determinant gene related to JA synthesis that regulates the production of male unisexual flowers in maize. The analysis of TS2 homologous gene expression in some plants suggests that TS2 protein may produce functional disambiguation during evolution. In order to investigate whether the function of TS2 protein has been disproportionated during evolution, the TS2 gene of rice and maize was compared and analyzed by bioinformatics. Molecular evolution analysis indicated that the TS2 gene in some plants may not be limited to the sex-determining function that inhibits the development of pistil. Therefore, it is speculated that TS2 in hermaphroditic plant rice may have other functions. Using the software of protein three-dimensional structure prediction, it was found that rice TS2 gene encodes typical SDR protein, containing conserved GASGIG and YTASK motifs, and its substrate may be similar to maize TS2 protein. Promoter analysis showed that there were differences in hormone response elements between OsTS2 and maize TS2. Then, the tissue and organ expression of OsTS2 and maize TS2 were analyzed by RNA-seq data, and the effect of exogenous me JA spraying on the expression of TS2 gene in OsTS2 and maize was investigated by real-time fluorescence quantitative technique. The results showed that OsTS2 was mainly expressed in inflorescences, and the expression of TS2 in maize was the highest in the leaves at the critical stage of spike differentiation, and the expression of OsTS2 was significantly increased after treatment with exogenous MeJA. The difference between the expression of rice TS2 and maize TS2 suggests that rice TS2 may have different function from maize TS2, which provides clues for further understanding the function of TS2 in hermaphrodite flower plants.
【作者单位】：沈阳农业大学生物科学技术学院辽宁省农业生物技术重点实验室;农业部东北水稻生物学与遗传育种重点实验室;
【基金】：国家自然科学基金项目(31071422)
【分类号】：S511

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