北京大学瞿礼嘉团队揭示拟南芥中阻止多精受精的分子机制。
研究人员表示，一个卵子被多个精子受精（多精受精）会导致致命的基因组不平衡和染色体分离缺陷。在拟南芥中，阻止多精受精的机制是通过防止多管齐下（多个花粉管到达一个胚珠）来促进的。
研究人员发现，位于隔膜的FERONIA、ANJEA和HERCULES RECEPTOR KINASE 1受体样激酶与花粉管特异性的RALF6、7、16、36和37肽配体相互作用，从而建立这种多管阻断。RALF（快速碱化因子）肽和受体复合物的相同组合控制花粉管在目标胚珠内的接收和破裂。花粉管破裂后释放出隔膜处的多管阻隔，这使得受精失败后出现了次级花粉管。因此，拟南芥受精过程中的步骤是由相同的信号成分协调的，从而保证和优化生殖成功。
附：英文原文
Title: RALF peptide signaling controls the polytubey block in Arabidopsis
Author: Sheng Zhong, Ling Li, Zhijuan Wang, Zengxiang Ge, Qiyun Li, Andrea Bleckmann, Jizong Wang, Zihan Song, Yihao Shi, Tianxu Liu, Luhan Li, Huabin Zhou, Yanyan Wang, Li Zhang, Hen-Ming Wu, Luhua Lai, Hongya Gu, Juan Dong, Alice Y. Cheung, Thomas Dresselhaus, Li-Jia Qu
Issue&Volume: 2022-01-21
Abstract: Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In Arabidopsis thaliana, the block to polyspermy is facilitated by a mechanism that prevents polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube–specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in Arabidopsis are coordinated by the same signaling components to guarantee and optimize reproductive success.
DOI: abl4683
Source: https://www.science.org/doi/10.1126/science.abl4683