Key Laboratory of Landscaping Agriculture, Ministry of Agriculture and Rural Affairs, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
Jiangsu Graduate Workstation of Nanjing Agriculture University and Nanjing Oriole Island Modern Agricultural Development Co., Ltd, Nanjing 210043, China.
Plant Cell Physiol. 2021 Dec 10;62(11):1687-1701. doi: 10.1093/pcp/pcab124.
Male sterility, as a common reproductive characteristic in plants, plays an important role in breeding, in which pollen abortion is a key factor leading to male sterility. Here, based on a low expression level gene CmACOS5 in transcriptome of pollen abortive chrysanthemum, a new transcription factor CmLBD2 of the Lateral Organ Boundaries Domain family, which could bind the promoter of CmACOS5 by yeast one-hybrid library was screened. This study revealed the origin and expression pattern of CmLBD2 in chrysanthemum and verified the functions of two genes in pollen development by transgenic means. Inhibiting the expression of CmACOS5 or CmLBD2 can lead to a large reduction in pollen and even abortion in chrysanthemum. Using yeast one-/two-hybrid, electrophoretic mobility shift assays, and luciferase reporter assays, it was verified that CmLBD2 directly binds to the promoter of CmACOS5. These results suggest that LBD2 is a novel, key transcription factor regulating pollen development. This result will provide a new research background for enriching the function of LBD family proteins and also lay a new foundation for the breeding of male sterile lines and the mechanism of pollen development.
雄性不育作为植物中一种常见的生殖特征，在植物育种中起着重要作用，其中花粉败育是导致雄性不育的关键因素。在这里，基于花粉败育菊花转录组中低表达水平的基因 CmACOS5，筛选到一个新的侧生器官边界域家族转录因子 CmLBD2，该转录因子可以通过酵母单杂交文库结合 CmACOS5 的启动子。本研究揭示了菊花中 CmLBD2 的起源和表达模式，并通过转基因手段验证了两个基因在花粉发育中的功能。抑制 CmACOS5 或 CmLBD2 的表达可导致菊花花粉大量减少甚至败育。利用酵母单杂交/双杂交、电泳迁移率变动分析和荧光素酶报告基因分析，验证了 CmLBD2 可直接结合 CmACOS5 的启动子。这些结果表明 LBD2 是一种调控花粉发育的新型关键转录因子。该结果将为丰富 LBD 家族蛋白的功能提供新的研究背景，也为雄性不育系的选育和花粉发育机制奠定新的基础。
