nature

当前位置: Nature » 基因&基因组学 » 正文

中国学者在Nature子刊发布首个调控稻米垩白的Chalk5基因克隆

摘要 : 近日,中科院院士张启发和由他领衔的华中农业大学作物遗传改良国家重点实验室的国家自然科学基金创新研究群体在国家自然科学基金等项目的支持下,成功克隆了第一个稻米垩白率的主效基因Chalk5,并对其调控垩白形成的分子与细胞学机理进行了深入研究。功能研究显示,该基因在稻米优质分子育种中具有广阔的应用前景。相关成果于3月16日在线发表于国际顶级遗传学杂志《自然—遗传学》。

 垩白是灌浆期胚乳淀粉粒和蛋白质颗粒排列疏松而充气所形成的白色不透明部分。它极大地影响了稻米可食用性产量,同时对稻米透明度等外观品质、蒸煮食味和营养品质等都有大的影响。

多年来,科学家们一直致力于寻找控制垩白的关键基因,经过近10年研究,该团队终于首次分离克隆到其中一个关键基因Chalk5。Chalk5基因对很多稻米品质性状具有大的普遍性影响,尤其是极大地影响外观品质、精米产量和储藏蛋白质的总含量。

研究成果不仅为优质稻米的分子育种提供了目标基因,还为水稻优质育种实践提供了理论指导,同时为进一步阐明作物品质调控的生物学机理提供了理论依据,而且为解释稻米产量与品质的矛盾与统一提供了遗传与分子证据。

原文摘要:

Chalk5 encodes a vacuolar H+-translocating pyrophosphatase influencing grain chalkiness in rice

Yibo Li,Chuchuan Fan,Yongzhong Xing,Peng Yun,Lijun Luo,Bao Yan,Bo Peng,Weibo Xie,Gongwei Wang,Xianghua Li,Jinghua Xiao,Caiguo Xu & Yuqing He

Grain chalkiness is a highly undesirable quality trait in the marketing and consumption of rice grain. However, the molecular basis of this trait is poorly understood. Here we show that a major quantitative trait locus (QTL), Chalk5, influences grain chalkiness, which also affects head rice yield and many other quality traits. Chalk5 encodes a vacuolar H+-translocating pyrophosphatase (V-PPase) with inorganic pyrophosphate (PPi) hydrolysis and H+-translocation activity. Elevated expressi0n of Chalk5 increases the chalkiness of the endosperm, putatively by disturbing the pH homeostasis of the endomembrane trafficking system in developing seeds, which affects the biogenesis of protein bodies and is coupled with a great increase in small vesicle-like structures, thus forming air spaces among endosperm storage substances and resulting in chalky grain. Our results indicate that two consensus nucleotide polymorphisms in the Chalk5 promoter in rice varieties might partly account for the differences in Chalk5 mRNA levels that contribute to natural variation in grain chalkiness.

来源: 中国科学报 浏览次数:117

热门文章TOP

RSS订阅 - 填写您的邮件地址,订阅我们的精彩内容: - 网站地图
网站联系电话:020-87540820 备案号:粤ICP备11050685号-8 增值电信业务经营许可证:粤B2-20120479
©2011-2015 生物帮 All rights reserved.