OsPKS1 is required for sexine layer formation, which shows functional conservation between rice and Arabidopsis
OsPKS1 is required for sexine layer formation, which shows functional conservation between rice and Arabidopsis
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OsPKS1 是性腺层形成所必需的，这表明水稻和拟南芥之间的功能保守
DOI：
10.1016/j.plantsci.2018.08.009
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发表时间：
2018-12-01
期刊：
影响因子：
5.2
通讯作者：
Zhu, Jun
中科院分区：
文献类型：
--
作者：
Shi, Qiang-Sheng;Wang, Kai-Qi;Zhu, Jun
孢粉素前体是花粉外壁的主要成分，在绒毡层中合成，经运输和加工后沉积在花粉表面。聚酮合酶将酰基辅酶A缩合成羟烷基α-吡喃酮，其被预测为孢粉素前体的组分。本研究通过序列比对发现水稻多聚酮合成酶1（OsPKS 1）与拟南芥多聚酮合成酶A/少粘花粉6（PKSA/LAP 6）同源。通过Crispr-Cas9介导的编辑获得的OsPKS 1敲除突变体表现出完全的雄性不育表型。细胞学观察表明，异常杆状沉积和ubisch体结构的性线形成导致花粉破裂ospks 1。表达分析表明，OsPKS 1基因在水稻花药发育的第9 ~ 11期绒毡层细胞和药室中高表达。亚细胞定位表明OsPKS 1蛋白优先定位于ER。由PKSA/LAP 6启动子驱动的OsPKS 1基因组序列恢复了拟南芥pksa/lap 6的性线模式。这些结果表明OsPKS 1基因是水稻性线层形成所必需的，并且在孢粉素合成途径中具有保守的功能。
The sporopollenin precursors, as a general constituent of sexine, are synthesized in the tapetum and deposited on the pollen surface after transportation and processing. The polyketide synthase condenses the acyl-CoA into a hydroxyalkyl alpha-pyrone, which is predicted to be a component of the sporopollenin precursors. In this study, we found that the rice POLYKETIDE SYNTHASE 1 (OsPKS1) was the orthologue of Arabidopsis POLYKETIDE SYNTHASE A/LESS ADHESIVE POLLEN 6 (PKSA/LAP6) through sequence alignment. The OsPKS1 knockout mutants obtained by Crispr-Cas9-mediated editing exhibited a complete male sterile phenotype. Cytological observations revealed that abnormal bacula deposition and ubisch body structures for sexine formation led to pollen rupture in ospks1. The expression analysis showed that the OsPKS1 was highly expressed in tapetal cells and anther locules from stage 9 to stage 11 during anther development in rice. Subcellular localization demonstrated that the OsPKS1 protein was preferentially localized to the ER. The genomic sequence of OsPKS1 driven by the PKSA/LAP6 promoter restored the sexine pattern of Arabidopsis pksa/lap6. These results indicated that OsPKS1 is required for sexine layer formation in rice and functionally conserved in the sporopollenin synthesis pathway.