PDF(Pubmed)
Abstract：
Several closely related Myb-like activator proteins are known to have partially redundant functions within the plant circadian clock, but their specific roles are not well understood. To clarify the function of the REVEILLE 4, REVEILLE 6, and REVEILLE 8 transcriptional activators, we characterized the growth and clock phenotypes of CRISPR-Cas9-generated single, double, and triple rve mutants. We found that these genes act synergistically to regulate flowering time, redundantly to regulate leaf growth, and antagonistically to regulate hypocotyl elongation. We previously reported that increasing intensities of monochromatic blue and red light have opposite effects on the period of triple rve468 mutants. Here, we further examined light quality-specific phenotypes of rve mutants and report that rve468 mutants lack the blue light-specific increase in expression of some circadian clock genes observed in wild type. To investigate the basis of these blue light-specific circadian phenotypes, we examined RVE protein abundances and degradation rates in blue and red light and found no significant differences between these conditions. We next examined genetic interactions between RVE genes and ZEITLUPE and ELONGATED HYPOCOTYL5, two factors with blue light-specific functions in the clock. We found that the RVEs interact additively with both ZEITLUPE and ELONGATED HYPOCOTYL5 to regulate circadian period, which suggests that neither of these factors are required for the blue light-specific differences that we observed. Overall, our results suggest that the RVEs have separable functions in plant growth and circadian regulation and that they are involved in blue light-specific circadian signaling via a novel mechanism.
摘要：
已知几种密切相关的Myb样激活蛋白在植物生物钟内具有部分冗余功能，但是他们的具体角色还没有得到很好的理解。为了阐明REVEILLE4、REVEILLE6和REVEILLE8转录激活子的功能，我们表征了CRISPR-Cas9产生的单一的生长和时钟表型，双,和三重rve突变体。我们发现这些基因协同调节开花时间,多余地调节叶片生长，并拮抗调节下胚轴伸长。我们先前报道，单色蓝光和红光强度的增加对三重rve468突变体的周期具有相反的影响。这里,我们进一步检查了rve突变体的光质量特异性表型，并报告rve468突变体缺乏野生型中观察到的一些昼夜节律基因表达的蓝光特异性增加。为了研究这些蓝光特异性昼夜节律表型的基础，我们检查了蓝光和红光下的RVE蛋白丰度和降解率，发现这些条件之间没有显着差异。接下来，我们研究了RVE基因与ZEITLUEP和ELONGATedHYPOTYL5之间的遗传相互作用，这两个因素在时钟中具有蓝光特异性功能。我们发现RVE与ZeITLUEP和ELONGATedHYPOCOTYL5相加相互作用以调节昼夜节律，这表明，这两个因素都不是我们观察到的蓝光特异性差异所必需的。总的来说,我们的结果表明,RVE在植物生长和昼夜节律调节中具有可分离的功能,并且它们通过一种新的机制参与蓝光特异性昼夜节律信号传导.
