AH2 encodes a MYB domain protein that determines hull fate and affects grain yield and quality in rice

• DOI: 10.1111/tpj.14481
• Publication Date: 2019-07-29T22:31:22Z
• Authors: Deyong Ren; Yuanjiang Cui; Haitao Hu; Qiankun Xu; Yuchun Rao; Xiaoqi Yu; Yu Zhang; Yuexing Wang; Youlin Peng; Dali Zeng; Jiang Hu; Guangheng Zhang; Zhenyu Gao; Li Zhu; Guang Chen; Lan shen; Qiang Zhang; Longbiao Guo; Qian Qian
• Keywords: 2. Zero hunger; 0301 basic medicine; 0303 health sciences; Oryza; Flowers; Plants, Genetically Modified; Plant Epidermis; 03 medical and health sciences; Gene Expression Regulation, Plant; Mutation; Seeds; Cloning, Molecular; Plant Proteins; Transcription Factors

SummaryThe palea and lemma (hull) are grass‐specific organs, and determine grain size and quality. In the study, AH2 encodes a MYB domain protein, and functions in the development of hull and grain. Mutation of AH2 produces smaller grains and alters grain quality including decreased amylose content and gel consistency, and increased protein content. Meantime, part of the hull lost the outer silicified cells, and induces a transformation of the outer rough epidermis to inner smooth epidermis cells, and the body of the palea was reduced in the ah2 mutant. We confirmed the function of AH2 by complementation, CRISPR‐Cas9, and cytological and molecular tests. Additionally, AH2, as a repressor, repress transcription of the downstream genes. Our results revealed that AH2 plays an important role in the determination of hull epidermis development, palea identity, and grain size.