Isolation and initial characterization of GW5, a major QTL associated with rice grain width and weight
Isolation and initial characterization of GW5, a major QTL associated with rice grain width and weight
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DOI：
10.1038/cr.2008.307
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发表时间：
2008-12-01
期刊：
影响因子：
44.1
通讯作者：
Wan, Jianmin
中科院分区：
文献类型：
--
作者：
Weng, Jianfeng;Gu, Suhai;Wan, Jianmin
粒重是决定作物产量的主要因素，受自然存在的数量性状基因座（QTL）控制。我们之前鉴定了一个控制水稻粒宽和粒重的主效QTL GW 5，定位于水稻5号染色体上的重组热点。为了更好地了解GW 5如何控制水稻粒宽，我们对该位点进行了精细定位，发现了一个1 212 bp的缺失与水稻品种Asominori的粒宽增加，与细粒水稻IR 24相比。此外，对46个水稻品种的基因型分析表明，该缺失与粒宽表型高度相关，这表明GW 5缺失可能是在水稻驯化过程中选择的。GW 5编码一种定位于细胞核的144个氨基酸的新型核蛋白。此外，我们表明，GW 5物理相互作用与聚泛素在酵母双杂交试验。总之，我们的研究结果表明，GW 5代表了水稻宽度和重量的主要QTL，它可能在种子发育过程中通过泛素-蛋白酶体途径调节细胞分裂。该研究为水稻籽粒发育的分子调控机制提供了新的见解，并表明GW 5可作为作物高产育种的潜在工具。
Grain weight is a major determinant of crop grain yield and is controlled by naturally occurring quantitative trait loci (QTLs). We earlier identified a major QTL that controls rice grain width and weight, GW5, which was mapped to a recombination hotspot on rice chromosome 5. To gain a better understanding of how GW5 controls rice grain width, we conducted fine mapping of this locus and uncovered a 1 212-bp deletion associated with the increased grain width in the rice cultivar Asominori, in comparison with the slender grain rice IR24. In addition, genotyping analyses of 46 rice cultivars revealed that this deletion is highly correlated with the grain-width phenotype, suggesting that the GW5 deletion might have been selected during rice domestication. GW5 encodes a novel nuclear protein of 144 amino acids that is localized to the nucleus. Furthermore, we show that GW5 physically interacts with polyubiquitin in a yeast two-hybrid assay. Together, our results suggest that GW5 represents a major QTL underlying rice width and weight, and that it likely acts in the ubiquitin-proteasome pathway to regulate cell division during seed development. This study provides novel insights into the molecular mechanisms controlling rice grain development and suggests that GW5 could serve as a potential tool for high-yield breeding of crops.