【作者】 赵峰；

【导师】 赵德刚； 傅永福；

【作者基本信息】 贵州大学 ， 生物化学与分子生物学， 2008， 硕士

【摘要】 植物感受外界光信号的变化,并改变体内一些重要基因的表达,从而导致生长发育的变化。这种信号传导系统包括光信号输入途径,生物钟振荡器系统和信号输出系统三部分。ZTL蛋白既是蓝光受体,又影响生物钟蛋白的稳定性,调节生物钟的功能和正常运转。本研究以对拟南芥基因AtZTL功能较详细的研究为基础,以拟南芥为研究材料,以大豆基因GmZTL为研究对象,应用一定技术分析研究GmZTL蛋白在调控生物振荡器和信号输出路径及光周期影响开花途径中的生物学功能。通过生物信息学分析发现,GmZTL和AtZTL的同源性高达85.9%,但是GmZTL蛋白还含有一个WD、两个F-Box、一个Radical SAM、一个PPR重复区域,这些功能区域在AtZTL中是没有的。以拟南芥为材料分别过表达GmZTL、GFP:GmZTL和GmZTL:GFP等基因,发现这些过表达植株的表现型与AtZTL过表达植株的表现型十分类似:(1)GmZTL过表达植株在长日下和野生型相比表现出晚开花,但是在短日下,部分GmZTL过表达植株又表现出和野生型相比晚花的表现型;(2)GFP:GmZTL和GmZTL:GFP过表达植株表现出和GmZTL过表达植株相类似的表现型;(3)GmZTL过表达植株在红光下表现出下胚轴伸长,但在蓝光下的表现型与野生型一致;(4)GmZTL mRNA的表达无论在长日还是在短日下都没有生物节律的变化;(5)GmZTL在上胚轴、单叶、第三复叶、花和荚中的表达水平很高,为组成型表达。结果表明,大豆GmZTL可能具有拟南芥ZTL类似的功能,但还具有拟南芥ZTL所不具备的新功能,是生物钟的调节元件之一。本研究结果为开花分子机理的深入研究和生产应用奠定了重要基础。更多还原

【Abstract】 The plant perceives the environmental signals and alters in its development pathway by changing the expression patterns of many genes.This signal cascade includes the input pathway of the clock,the central oscillator and the output pathway of the clock. ZTL protein not only acts as a photoreceptor of blue light,but also influences the stabilization of the clock protein and regulates clock functions and maintains regular running of the clock.This research is based on the detailed functional understand of AtZTL and take Arabidopsis as research material and GmZTL as object to study.We applied some technologies to study the biological function of GmZTL protein in regulating biological oscillator and signal output ways and the influence of photoperiod to flowering pathway.The analysis of bioinformatics of GmZTL and AtZTL showed that there is 85.9% identity between them and they are in the closest relation compared to homologs in other plants.There are several domains found in GmZTL but not in AtZTL,such as a WD,two F-Box,a Radical SAM and a PPR repeat.We have created the overexpressors of GmZTL,GFP:GmZTL and GmZTL:GFP in Arabidopsis and found that these overexpressors showed a very similar phenotype with that of AtZTL.(1) The overexpressors of GmZTL flower late in long days compared to the wild type.But in short days many overexpressors of GmZTL show a phenotype of early flowering compared to wild type(2) The overexpressors of GFP:GmZTL and GmZTL:GFP show a very similar phenotype with the overexpressors of GmZTL.(3) Compared to their parents(ztl mutation),the overexpressors of GmZTL have a long hypocotyl in red light,but not in blue light.(4) The expression of GmZTL mRNA did not show circadian change in long days or short days.(5) GmZTL is constitutive expression,but high levels in epicotyls,unifoliolates,the third trifoliolates,flowers and pods.In summary,GmZTL may have not only similar functions to that of AtZTL but some new functions,and it is a regulator of the clock.The results paved a way in further researching in the molecular mechanism of flowering and the production in soybean.更多还原