日前，上海交通大学张大兵教授指导的博士生胡丽芳在水稻花药发育分子机制研究上获得新进展。该项研究找到了水稻MADS-box基因MADS3的一个新突变位点，该突变体（mads3-4）花药发育后期花药转变成异常的褐色，花粉败育，表现为完全雄性不育。深入研究发现，MADS3可以控制MT-1-4b等基因表达来调节花药发育后期活性氧分子的动态平衡，当该基因突变后，花药中会异常积累活性氧分子，影响花药发育和花粉的成熟。这个工作提出了水稻花药发育和花粉形成一个新的分子机制，为阐明植物生殖发育机制以及水稻遗传改良提供基础。该论文2011年2月6日在植物分子生物学领域的著名刊物《The Plant Cell》上在线发表（）。

论文摘要：

The rice (Oryza sativa) floral homeotic C-class gene, MADS3, was previously shown to be required for stamen identity determination during early flower development. Here, we describe a role for MADS3 in regulating late anther development and pollen formation. Consistent with this role, MADS3 is highly expressed in the tapetum and microspores during late anther development, and a newly identified MADS3 mutant allele, mads3-4, displays defective anther walls, aborted microspores, and complete male sterility. During late anther development, mads3-4 exhibits oxidative stress-related phenotypes. Microarray analysis revealed expression level changes in many genes in mads3-4 anthers. Some of these genes encode proteins involved in reactive oxygen species (ROS) homeostasis; among them is MT-1-4b, which encodes a type 1 small Cys-rich and metal binding protein. In vivo and in vitro assays showed that MADS3 is associated with the promoter of MT-1-4b, and recombinant MT-1-4b has superoxide anion and hydroxyl radical scavenging activity. Reducing the expression of MT-1-4b causes decreased pollen fertility and an increased level of superoxide anion in transgenic plants. Our findings suggest that MADS3 is a key transcriptional regulator that functions in rice male reproductive development, at least in part, by modulating ROS levels through MT-1-4b.

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