A QTL for rice grain width and weight encodes a previously unknown RING-type E3 ubiquitin ligase
A QTL for rice grain width and weight encodes a previously unknown RING-type E3 ubiquitin ligase
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DOI：
10.1038/ng2014
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发表时间：
2007-05-01
期刊：
影响因子：
30.8
通讯作者：
Lin, Hong-Xuan
中科院分区：
文献类型：
--
作者：
Song, Xian-Jun;Huang, Wei;Lin, Hong-Xuan
粒重是影响产量的重要因素之一，受来自作物自然变异的数量性状基因座（QTL）控制。然而，QTL在粒重调控中的分子作用尚未完全阐明。在这里，我们报告的GW 2，一个新的QTL，控制水稻粒宽和粒重的克隆和表征。我们的数据表明，GW 2编码一个以前未知的RING型蛋白与E3泛素连接酶的活性，这是已知的泛素-蛋白酶体途径的降解功能。GW 2功能的缺失增加了细胞数量，导致小穗船体变大（变宽），并加快了灌浆速率，从而提高了粒宽、粒重和产量。我们的研究结果表明，GW 2负调控细胞分裂，其底物（S）的蛋白酶体调节蛋白水解。GW 2的功能特性提供了对种子发育机制的深入了解，并且是提高作物谷物产量的潜在工具。
Grain weight is one of the most important components of grain yield and is controlled by quantitative trait loci (QTLs) derived from natural variations in crops. However, the molecular roles of QTLs in the regulation of grain weight have not been fully elucidated. Here, we report the cloning and characterization of GW2, a new QTL that controls rice grain width and weight. Our data show that GW2 encodes a previously unknown RING-type protein with E3 ubiquitin ligase activity, which is known to function in the degradation by the ubiquitin-proteasome pathway. Loss of GW2 function increased cell numbers, resulting in a larger ( wider) spikelet hull, and it accelerated the grain milk filling rate, resulting in enhanced grain width, weight and yield. Our results suggest that GW2 negatively regulates cell division by targeting its substrate(s) to proteasomes for regulated proteolysis. The functional characterization of GW2 provides insight into the mechanism of seed development and is a potential tool for improving grain yield in crops.