当前位置: X-MOL 学术J. Exp. Bot. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The NAC transcription factor NAC019-A1 is a negative regulator of starch synthesis in wheat developing endosperm.
Journal of Experimental Botany ( IF 5.6 ) Pub Date : 2020-08-17 , DOI: 10.1093/jxb/eraa333
Yunchuan Liu 1, 2 , Jian Hou 1 , Xiaolu Wang 1 , Tian Li 1 , Uzma Majeed 1 , Chenyang Hao 1 , Xueyong Zhang 1
Affiliation  

Abstract
Starch is a major component of wheat (Triticum aestivum L.) endosperm and is an important part of the human diet. The functions of many starch synthesis genes have been elucidated. However, little is known about their regulatory mechanisms in wheat. Here, we identified a novel NAC transcription factor, TaNAC019-A1 (TraesCS3A02G077900), that negatively regulates starch synthesis in wheat and rice (Oryza sativa L.) endosperms. TaNAC019-A1 was highly expressed in the endosperm of developing grains and encoded a nucleus-localized transcriptional repressor. Overexpression of TaNAC019-A1 in rice and wheat led to significantly reduced starch content, kernel weight, and kernel width. The TaNAC019-A1-overexpression wheat lines had smaller A-type starch granules and fewer B-type starch granules than wild-type. Moreover, TaNAC019-A1 could directly bind to the ‘ACGCAG’ motif in the promoter regions of ADP-glucose pyrophosphorylase small subunit 1 (TaAGPS1-A1, TraesCS7A02G287400) and TaAGPS1-B1 (TraesCS7B02G183300) and repress their expression, thereby inhibiting starch synthesis in wheat endosperm. One haplotype of TaNAC019-B1 (TaNAC019-B1-Hap2, TraesCS3B02G092800) was positively associated with thousand-kernel weight and underwent positive selection during the Chinese wheat breeding process. Our data demonstrate that TaNAC019-A1 is a negative regulator of starch synthesis in wheat endosperm and provide novel insight into wheat yield improvement.
更新日期:2020-10-08
down
wechat
bug