The LCG1‐OsBP5 OsEBP89‐Wx module regulates the grain chalkiness and taste quality

Bin Tu, Tao Zhang, Pin Liu, Wen Yang, Ling Zheng, Ying Dai, Hao Wang, Song Lin, Zehua Zhang, Xiaohang Zheng, Mengting Yuan, Yong Chen, Xiaobo Zhu, Hua Yuan, Ting Li, Jiawei Xiong, Zhaohui Zhong, Weilan Chen, Bingtian Ma, Peng Qin, Yuping Wang, Shigui Li

Plant Biotechnol J, . 2024 Sep 23.( IF=10.1)

https://pubmed.ncbi.nlm.nih.gov/39312475/

Abstract

It is well known that the overall quality of japonica/geng rice is superior to that of indica/xian rice varieties. However, the molecular mechanisms underlying the quality disparities between these two subspecies of rice are still largely unknown. In this study, we have pinpointed a gene homologous to SLR1, termed LCG1, exhibiting significant expression during early caryopsis development and playing a specific role in regulating rice chalkiness and taste by affecting the accumulation of grain storage components, starch granule structure and chain length distribution of amylopectin. LCG1 physically interacts with OsBP5 and indirectly influences the expression of the amylose synthesis gene Waxy (Wx) by hindering the transcriptional activity of the OsBP5/OsEBP89 complex. Notably, sequence variations in the promoter region of LCG1 result in enhanced transcription in japonica rice accessions. This leads to elevated LCG1 expression in CSSL-LCG1Nip, thereby enhancing rice quality. Our research elucidates the molecular mechanism underlying the impact of the LCG1-OsBP5/OsEBP89-Wx regulatory pathway on rice chalkiness and taste quality, offering new genetic resources for improving the indica rice quality.

Keywords: LCG1; OsBP5/OsEBP89 complex; Wx; grain chalkiness; rice; taste quality.