内源生物钟的节律运动不仅调控植物的生长发育,而且在调控植物响应和适应环境过程中发挥重要的作用。为了解水稻(Oryza sativa L.)干旱胁迫响应基因和生物钟基因在干旱条件下每日表达变化情况,本文利用实时荧光定量PCR方法研究旱稻品种IRAT109在干旱胁迫下相关基因的表达变化。结果表明,干旱胁迫导致早晨生物钟基因OsPRRs、OsLHY和OsZTL1的表达量显著下降,振幅减弱;同时导致夜晚生物钟基因OsTOC1、OsGI和OsELF3整体表达量升高,振幅增强,但对OsFKF1基因影响不大。同样,大部分水稻干旱胁迫响应基因在干旱胁迫后整体表达量显著升高,但OsDST基因表达量下降;同时大部分抗逆基因周期性表达被扰乱,但OsCIPK12、OsCDPK7和OsDREB1A依然保持24 h内震荡。本研究结果表明干旱胁迫能影响生物钟元件的基因表达,这种互相影响改变了部分基因每日的震荡变化。

Endogenous circadian rhythms play a key role in regulating plant growth and development, and in allowing plants to respond and adapt to changing environments. To understand how drought regulates upland rice(Oryza sativa L.) IRAT109, we examined the expression levels of circadian clock and drought-responsive genes through real-time PCR. The results revealed that, first, drought reduced the relative expression level and amplitude of peak expression of several morning circadian clock components (such as OsPRRs, OsLHY and OsZTL1), increased the relative expression level and amplitude of some evening circadian clock components (such as OsTOC1, OsGI and OsELF3), but did not influence OsFKF1. Secondly, the relative expression level of most drought-responsive genes was generally increased, except for OsDST, a negative regulator. Lastly, expression rhythms of most drought-responsive genes were disturbed, but not that of OsCIPK12, OsCDPK7 and OsDREB1A. The results indicate that drought stress modulates the expression of circadian clock components and the interplay regulates diurnal oscillations of relative genes.