The Arabidopsis CrRLK1L protein kinases BUPS1 and BUPS2 are required for normal growth of pollen tubes in the pistil
The Arabidopsis CrRLK1L protein kinases BUPS1 and BUPS2 are required for normal growth of pollen tubes in the pistil
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拟南芥 CrRLK1L 蛋白激酶 BUPS1 和 BUPS2 是雌蕊中花粉管正常生长所必需的
DOI：
10.1111/tpj.13963
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发表时间：
2018-08-01
期刊：
影响因子：
7.2
通讯作者：
Ye, De
中科院分区：
文献类型：
--
作者：
Zhu, Lei;Chu, Liang-Cui;Ye, De
在有花植物中，花粉管与雌性组织的相互作用对于双受精的完成是重要的。关于花粉管和雌性组织之间的信号传递机制，人们知之甚少。在这项研究中，两个拟南芥花粉管表达CrRLK1L蛋白激酶，佛纸密封1（BUPS1）和BUPS2，被确定为所需的正常顶端生长的花粉管在雌蕊。它们在花粉和花粉管中大量表达，并定位于花粉管尖端区域的质膜上。BUPS1的突变大大减少了种子集。大多数bups1突变体的花粉管生长在雌蕊中，表现出肿胀的花粉管尖端，导致受精失败。bups2的花粉管形态稍有异常，但仍能完成双受精。bups1 bups2双突变体表现出轻微增强的表型相比，单bups1突变体。BUPS1蛋白可以与BUPS2形成同聚体和异聚体，而BUPS2只能与BUPS1形成异聚体。酵母双杂交（Y2H）和双分子荧光互补（BiFC）分析表明，BUPS蛋白可以与拟南芥花粉表达的RopGEFs相互作用。结果表明，BUPSs可能介导雌蕊中花粉管的正常极性生长。
In flowering plants, the interaction of pollen tubes with female tissues is important for the accomplishment of double fertilization. Little information is known about the mechanisms that underlie signalling between pollen tubes and female tissues. In this study, two Arabidopsis pollen tube-expressed CrRLK1L protein kinases, Buddha's Paper Seal 1 (BUPS1) and BUPS2, were identified as being required for normal tip growth of pollen tubes in the pistil. They are expressed prolifically in pollen and pollen tubes and are localized on the plasma membrane of the pollen tube tip region. Mutations in BUPS1 drastically reduced seed set. Most of the bups1 mutant pollen tubes growing in the pistil exhibited a swollen pollen tube tip, leading to failure of fertilization. The bups2 pollen tubes had a slightly abnormal morphology but could still accomplish double fertilization. The bups1 bups2 double mutant exhibited a slightly enhanced phenotype compared to the single bups1 mutants. The BUPS1 proteins could form homomers and heteromers with BUPS2, whereas BUPS2 could only form heteromers with BUPS1. The BUPS proteins could interact with the Arabidopsis pollen-expressed RopGEFs in the yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. The results indicated that the BUPSs may mediate normal polar growth of pollen tubes in the pistil.