NARROW AND ROLLED LEAF 2 regulates leaf shape,male fertility,and seed size in rice

Grain yield in rice(Oryza sativa L.) is closely related to leaf and flower development. Coordinative regulation of leaf, pollen, and seed development in rice as a critical biological and agricultural question should be addressed. Here we identified two allelic rice mutants with narrow and semirolled leaves, named narrow and rolled leaf 2-1(nrl2-1) and nrl2-2. Map-based molecular cloning revealed that NRL2 encodes a novel protein with unknown biochemical function. The mutation of NRL2 caused pleiotropic effects, including a reduction in the number of longitudinal veins, defective abaxial sclerenchymatous cell differentiation, abnormal tapetum degeneration and microspore development, and the formation of more slender seeds compared with the wild type(WT). The NRL2 protein interacted with Rolling-leaf(RL14),causing the leaves of the nrl2 mutants to have a highercellulose content and lower lignin content than the WT, which may have been related to sclerenchymatous cell differentiation and tapetum degeneration. Thus, this gene is an essential developmental regulator controlling fundamental cellular and developmental processes, serving as a potential breeding target for high-yielding rice cultivars.     

茶树花发育MADS-box转录因子CsGLO1、CsGLO2与CsAG之间的互作关系研究

利用酵母双杂交方法和双分子荧光互补技术（BiFC）研究了茶树（Camellia sinensis（L.）O.Kuntze）花发育MADS-box的B类转录因子CsGLO1、CsGLO2与C类转录因子CsAG间的互作关系及其可能发生互作的亚细胞定位。通过构建5个酵母表达载体,利用酵母单杂交实验检测了3个蛋白的转录激活活性,并通过酵母双杂交实验分析了蛋白间的互作关系。结果显示,3个蛋白均无转录激活活性,且两两之间可发生相互作用。进一步构建6个BiFC表达载体,采用压力注射法瞬时浸染烟草（Nicotiana benthamiana L.）叶表皮细胞,并利用激光共聚焦显微镜观察荧光信号,结果表明茶树B类CsGLO与C类CsAG蛋白可在植物活细胞内形成同源和异源二聚体,并具有在细胞质中发生互作的特定模式。本研究可为利用分子生物学技术抑制茶树“花果同现”现象提供理论依据。