Background

The plant chloroplast is essential for photosynthesis and other cellular processes, but an understanding of the biological mechanisms of plant chloroplast development are incomplete.

Results

A new temperature-sensitive white stripe leaf 9(wsl9) rice mutant is described. The mutant develops white stripes during early leaf development, but becomes green after the three-leaf stage under field conditions. The wsl9 mutant was albinic when grown at low temperature. Gene mapping of the WSL9 locus, together with complementation tests indicated that WSL9 encodes a novel protein with an HNH domain. WSL9 was expressed in various tissues. Under low temperature, the wsl9 mutation caused defects in splicing of rpl2, but increased the editing efficiency of rpoB. Expression levels of plastid genome-encoded genes, which are transcribed by plastid-coded RNA polymerase (PEP), chloroplast development genes and photosynthesis-related genes were altered in the wsl9 mutant.

Conclusion

WSL9 encodes an HNH endonuclease domain-containing protein that is essential for early chloroplast development. Our study provides opportunities for further research on regulatory mechanisms of chloroplast development in rice.

中文翻译：

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WSL9编码一种HNH核酸内切酶结构域蛋白，该蛋白对于水稻早期叶绿体发育至关重要。

背景

植物叶绿体对于光合作用和其他细胞过程至关重要，但是对植物叶绿体发育的生物学机制的了解还不完整。

结果

描述了一种新的对温度敏感的白色条纹叶9 （wsl9 ）水稻突变体。该突变体在早期叶片发育过程中会形成白色条纹，但在田间条件下的三叶阶段后变为绿色。所述wsl9当在低温下生长的突变体是albinic。WSL9基因座的基因定位以及互补性测试表明，WSL9编码具有HNH结构域的新型蛋白质。WSL9在各种组织中表达。在低温度下，wsl9突变引起的剪接缺陷rpl2，但增加的编辑效率的rpoB 。在wsl9突变体中，质体基因组编码基因的表达水平被质体编码RNA聚合酶（PEP），叶绿体发育基因和光合作用相关基因转录。

结论

WSL9编码含有HNH核酸内切酶结构域的蛋白质，该蛋白质对于早期叶绿体发育至关重要。我们的研究为水稻叶绿体发育调控机制的进一步研究提供了机会。