Yield in rice is determined mainly by panicle architecture. Using map-based cloning, we identified an R2R3 MYB transcription factor REGULATOR OF GRAIN NUMBER1 (RGN1) affecting grain number and panicle architecture. Mutation of RGN1 caused an absence of lateral grains on secondary branches. We demonstrated that RGN1 controls lateral grain formation by regulation of LONELY GUY (LOG) expression, thus controlling grain number and shaping panicle architecture. A novel favourable allele, RGN1^C, derived from the Or-I group in wild rice affected panicle architecture by means longer panicles. Identification of RGN1 provides a theoretical basis for understanding the molecular mechanism of lateral grain formation in rice; RGN1 will be an important gene resource for molecular breeding for higher yield.

中文翻译：

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RGN1控制水稻粒数和穗形结构

水稻产量主要由穗结构决定。使用基于图谱的克隆，我们确定了影响谷物数量和圆锥花序结构的 R2R3 MYB 转录因子 GRAIN NUMBER1 (RGN1) 转录因子。RGN1的突变导致次生枝上没有侧粒。我们证明了RGN1通过调节LONELY GUY ( LOG ) 的表达来控制侧粒的形成，从而控制粒数和形成圆锥花序结构。一种新的有利等位基因，RGN1 ^C，来源于野生稻中的 Or-I 组，通过更长的穗来影响穗结构。RGN1的鉴定为理解水稻侧粒形成的分子机制提供理论依据；RGN1将成为高产分子育种的重要基因资源。