Qin Sun, Yunfu Li, Dianming Gong, Aoqing Hu, Wanshun Zhong, Hailiang Zhao, Qiang Ning, Zengdong Tan, Kun Liang, Luyao Mu, David Jackson, Zuxin Zhang, Fang Yang, Fazhan Qiu

Nature Communications, volume13, Article number: 5708(2022)

Published: 29 September 2022

Abstract

Maize early endosperm development is initiated in coordination with elimination of maternal nucellar tissues. However, the underlying mechanisms are largely unknown. Here, we characterize a major quantitative trait locus for maize kernel size and weight that encodes an EXPANSIN gene,ZmEXPB15. The encoded β-expansin protein is expressed specifically in nucellus, and positively controls kernel size and weight by promoting nucellus elimination. We further show that two nucellus-enriched transcription factors (TFs),ZmNAC11andZmNAC29, activateZmEXPB15expression. Accordingly, these two TFs also promote kernel size and weight through nucellus elimination regulation, and genetic analyses support their interaction withZmEXPB15. Importantly, hybrids derived from aZmEXPB15overexpression line have increased kernel weight, demonstrates its potential value in breeding. Together, we reveal a pathway modulating the cellular processes of maternal nucellus elimination and early endosperm development, and an approach to improve kernel weight.

原文链接：https://doi.org/10.1038/s41467-022-33513-4