Natural variation of an E3 ubiquitin ligase encoding gene Chalk9 regulates grain chalkiness in rice

• 全文链接

E3泛素连接酶编码基因Chalk9的自然变异调控水稻籽粒垩白度

关键词：

来源：

nature communications

全文链接：

//agri.nais.net.cn/topic/downloadFile/83c9223c-5745-440a-979b-d629a9a47caf

来源地址：

https://www.nature.com/articles/s41467-025-61683-4

资源所属：

马铃薯基因组设计育种

类型：

学术文献

语种：

中文

原文发布日期：

2025-07-15

摘要：

Grain chalkiness is an undesirable trait affecting rice quality, concerning both consumers and breeders. However, the genetic mechanisms underlying rice chalkiness remain largely elusive. Here, we identify Chalk9 as a major gene associated with grain chalkiness in a natural population. Chalk9 encodes an E3 ubiquitin ligase that targets OsEBP89 for its ubiquitination and degradation. Low expression of Chalk9 results in excessive accumulation of OsEBP89, disrupting the homeostasis of storage components and leading to the chalkiness phenotype. A 64-bp insertion/deletion in the Chalk9 promoter contributes to its differential transcriptional levels, thus causing chalkiness variation among rice varieties. Moreover, the elite allele Chalk9-L reduces grain chalkiness, without compromising yield. Chalk9-L is strongly selected in japonica but exhibits a complex evolutionary trajectory in indica. Our findings reveal the molecular and genetic mechanisms underlying chalkiness and provide a potential strategy for breeding rice varieties with improved quality.