The polyketide synthase OsPKS2 is essential for pollen exine and Ubisch body patterning in rice
The polyketide synthase OsPKS2 is essential for pollen exine and Ubisch body patterning in rice
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聚酮合酶 OsPKS2 对于水稻花粉外壁和 Ubisch 体模式至关重要
DOI：
10.1111/jipb.12574
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发表时间：
2017
影响因子：
11.4
通讯作者：
Liang Wanqi
中科院分区：
文献类型：
--
作者：
Zhu Xiaolei;Yu Jing;Shi Jianxin;Tohge Takayuki;Fernie Alisdair R;Meir Sagit;Aharoni Asaph;Xu Dawei;Zhang Dabing;Liang Wanqi
脂类和酚类物质的代谢对花粉外壁的形成具有重要作用。在拟南芥中，聚酮脱氢酶（PKSs）对孢粉素的生物合成和外壁的形成都是必需的。在这里，我们的特点的作用，聚酮合酶（OsPKS 2）在水稻雄性生殖。重组OsPKS 2催化脂肪酰辅酶A与丙二酰辅酶A缩合生成花粉外壁的主要成分三酮和四酮α-吡喃酮。事实上，theospks 2突变体具有缺陷的外壁图案，并且是雄性不育的。然而，突变体显示出没有显着减少孢粉素积累。与野生型相比，ospks 2的外壁中存在无限制的无定形顶盖层和连接层，且乌氏体的组织结构较弱。与opsisortholog的pksb/lap 5突变体一样，ospks 2在花药相关酚类化合物的谱中表现出广泛的变化。然而，不像epksb/lap 5，其中大多数检测到的酚类物质大幅下降，ospks 2积累较高水平的酚类物质。基于这些结果和我们观察到OsPKS 2不能完全恢复pksb/lap 5的外壁缺陷，我们认为PKS蛋白在进化过程中具有功能多样性。总的来说，我们的研究结果表明，PKSs代表了一个保守的和多样化的生化途径花药和花粉发育在高等植物。
Lipid and phenolic metabolism are important for pollen exine formation. InArabidopsis, polyketide synthases (PKSs) are essential for both sporopollenin biosynthesis and exine formation. Here, we characterized the role of a polyketide synthase (OsPKS2) in male reproduction of rice (Oryza sativa). Recombinant OsPKS2 catalyzed the condensation of fatty acyl‐CoA with malonyl‐CoA to generate triketide and tetraketide α‐pyrones, the main components of pollen exine. Indeed, theospks2mutant had defective exine patterning and was male sterile. However, the mutant showed no significant reduction in sporopollenin accumulation. Compared with the WT (wild type), ospks2displayed unconfined and amorphous tectum and nexine layers in the exine, and less organized Ubisch bodies. Like thepksb/lap5mutant of theArabidopsisortholog,ospks2showed broad alterations in the profiles of anther‐related phenolic compounds. However, unlikepksb/lap5, in which most detected phenolics were substantially decreased,ospks2accumulated higher levels of phenolics. Based on these results and our observation thatOsPKS2is unable to fully restore the exine defects in thepksb/lap5, we propose that PKS proteins have functionally diversified during evolution. Collectively, our results suggest that PKSs represent a conserved and diversified biochemical pathway for anther and pollen development in higher plants.