Open AccessAn Arabidopsis E3 ligase HUB 2 increases histone H2B monoubiquitination and enhances drought tolerance in transgenic cotton
Author(s) -
Chen Hong,
Feng Hao,
Zhang Xueyan,
Zhang Chaojun,
Wang Tao,
Dong Jiangli
Publication year - 2019
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12998
Subject(s) - biology , h3k4me3 , transgene , drought tolerance , genetically modified crops , ubiquitin ligase , gene , arabidopsis , botany , microbiology and biotechnology , genetics , promoter , gene expression , ubiquitin , mutant
Summary The HUB 2 gene encoding histone H2B monoubiquitination E3 ligase is involved in seed dormancy, flowering timing, defence response and salt stress regulation in Arabidopsis thaliana . In this study, we used the cauliflower mosaic virus (Ca MV ) 35S promoter to drive At HUB 2 overexpression in cotton and found that it can significantly improve the agricultural traits of transgenic cotton plants under drought stress conditions, including increasing the fruit branch number, boll number, and boll‐setting rate and decreasing the boll abscission rate. In addition, survival and soluble sugar, proline and leaf relative water contents were increased in transgenic cotton plants after drought stress treatment. In contrast, RNA i knockdown of Gh HUB 2 genes reduced the drought resistance of transgenic cotton plants. At HUB 2 overexpression increased the global H2B monoubiquitination (H2Bub1) level through a direct interaction with GhH2B1 and up‐regulated the expression of drought‐related genes in transgenic cotton plants. Furthermore, we found a significant increase in H3K4me3 at the DREB locus in transgenic cotton, although no change in H3K4me3 was identified at the global level. These results demonstrated that At HUB 2 overexpression changed H2Bub1 and H3K4me3 levels at the Gh DREB chromatin locus, leading the Gh DREB gene to respond quickly to drought stress to improve transgenic cotton drought resistance, but had no influence on transgenic cotton development under normal growth conditions. Our findings also provide a useful route for breeding drought‐resistant transgenic plants.