Abstract

Background

FPF1 (flowering-promoting factor 1) is one of the important family involved in the genetic control of flowering time in plant. Until now, limited knowledge concerning FPF1 family in rice has been understood.

Results

As a homologue of AtFPF1, FPF1-like protein 4 of rice (OsFPFL4) is expressed in various tissues of plants. The functions of OsFPFL4 in rice were investigated by the reverse genetics approaches. Plants overexpressing OsFPFL4 have shorter primary root, more lateral roots and adventitious roots than wild type; however, RNA interference (RNAi) of OsFPFL4 significantly inhibits the growth of root system, and also delays the flowering time in rice. Interestingly, increased or repressed expression of OsFPFL4 leads to shrunken anthers and abnormal pollen grains. It is well recognized that auxin plays important roles in plant root and flower development, and the root elongation is also regulated by reactive oxygen species (ROS) homeostasis. Here, our results show that rice plants overexpressing OsFPFL4 accumulate more auxin in the shoot and root, whereas RNAi lines have less auxin than wild type. As expected, the transcript levels of genes responsible for auxin biosynthesis and polar transport are altered in these OsFPFL4 transgenic plants. As to ROS, slightly higher ROS levels were detected in overexpression root and inflorescence than the counterparts of wild type; however, the ROS levels were significantly increased in the RNAi lines, due to increased expression of ROS-producers and reduced expression of ROS-scavengers.

Conclusion

Our results reveal that OsFPFL4 is involved in modulating the root and flower development by affecting auxin and ROS homeostasis in rice plants. OsFPFL4 controls auxin accumulation via affecting auxin biosynthesis and transport, and also modulates ROS homeostasis by balancing ROS producing and scavenging. Thus, auxin-mediated ROS production might play a role in regulating redox status, which controls plant root and flower development.

中文翻译：

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OsFPFL4通过影响水稻（水稻）中的生长素水平和ROS积累而参与根和花的发育

摘要

背景

FPF1（开花促进因子1）是参与植物开花时间遗传控制的重要家族之一。到目前为止，人们对水稻中FPF1家族的了解有限。

结果

作为同源物AtFPF1，FPF1样蛋白4水稻（OsFPFL4）在植物中的各种组织中表达。通过逆向遗传学方法研究了OsFPFL4在水稻中的功能。与野生型相比，过表达OsFPFL4的植物的主根更短，侧根和不定根更多。然而，OsFPFL4的RNA干扰（RNAi）显着抑制了根系的生长，并延迟了水稻的开花时间。有趣的是，OsFPFL4的表达增加或被抑制导致花药萎缩和花粉粒异常。众所周知，生长素在植物根和花的发育中起重要作用，并且根的伸长也受活性氧（ROS）稳态的调节。在这里，我们的结果表明，过表达OsFPFL4的水稻植物在茎和根中积累更多的生长素，而RNAi品系的生长素比野生型少。正如预期的那样，这些OsFPFL4中负责生长素生物合成和极性转运的基因的转录水平发生了变化。转基因植物。至于ROS，在过表达的根和花序中检测到的ROS水平比野生型的略高。然而，由于ROS产生子的表达增加和ROS清除剂的表达减少，RNAi系中的ROS水平显着增加。

结论

我们的结果表明，OsFPFL4通过影响水稻植物中的生长素和ROS稳态而参与调节根和花的发育。OsFPFL4通过影响植物生长素的生物合成和运输来控制植物生长素的积累，并通过平衡ROS的产生和清除来调节ROS的稳态。因此，生长素介导的ROS的产生可能在调节氧化还原状态中起作用，氧化还原状态控制着植物的根和花的发育。