The cotton HD-Zip transcription factor GhHB12 regulates flowering time and plant architecture via the GhmiR157-GhSPL pathway

First author: Xin He; Affiliations: Huazhong Agricultural University (华中农业大学): Wuhan, China

Corresponding author: Longfu Zhu 

Domestication converts perennial and photoperiodic ancestral cotton to day-neutral cotton varieties, and the selection of short-season cotton varieties is one of the major objectives of cotton breeding. However, little is known about the mechanism of flowering time in cotton. Here, we report a cotton HD-ZIP I-class transcription factor (GhHB12) specifically expressed in axillary buds (腋芽), which antagonisticlly interacts with GhSPL10/13 to repress the expression of GhFT, GhFUL, and GhSOC1, resulting in bushy architecture and delayed flowering under long-day conditions. We found that GhHB12-mediated ancestral upland cotton phenotypes (bushy architecture and delayed flowering) could be rescued under short-day conditions. We showed that overexpressing of GhrSPL10 partially rescues the bushy architecture and delayed flowering phenotypes, while overexpression of GhmiR157 reinforced these phenotypes in GhHB12-overexpressing plants. This study defines a regulatory module which regulates cotton architecture, phase transition and could be applied in the breeding of early maturing cotton varieties.

驯化将多年生光周期棉花祖先种转变成了日中性棉花品种，短季棉花棉花品种的选育是棉花育种中的主要目的之一。然而，对于控制棉花开花时间的分子机制了解得还很少。本文研究显示棉花HD-ZIP I类转录因子GhHB12特异性在腋芽中表达，与GhSPL10/13拮抗互作以抑制GhFT、GhFUL和GhSOC1的表达，导致长日照条件下密集株型和开花延迟。作者发现GhHB12介导的古老的陆地棉和密集株型和开花延迟表型可以在短日照的条件下被拯救。研究显示在过表达GhHB12的植株中过表达GhrSPL10会部分恢复密集株型和开花延迟表型，而过表达GhmiR157则会加强这些表型。本研究鉴定了调控棉花株型结构、状态转变的调控模块，对于早熟棉花品种的育种具有潜在应用价值。

通讯：朱龙付  (http://cpst.hzau.edu.cn/info/1015/1579.htm)

个人简介：2004年，华中农业大学，博士；2007-2008年，美国德州理工大学，合作研究；2014年，荷兰瓦赫宁根大学，合作研究。

研究方向：棉花与黄萎病菌互作分子机制研究；棉花基础免疫信号网络与调控；棉花早熟多抗分子育种。

doi: https://doi.org/10.1038/s42003-018-0234-0

Journal: Communications Biology

Published date: 13 December, 2018