GhALKBH10 negatively regulates salt tolerance in cotton

Changjiang Cui; Zhifeng Ma; Hui Wan; Jianbo Gao; Baoliang Zhou

doi:10.1016/j.plaphy.2022.09.029

GhALKBH10 negatively regulates salt tolerance in cotton

Plant Physiol Biochem. 2022 Dec 1:192:87-100. doi: 10.1016/j.plaphy.2022.09.029. Epub 2022 Oct 4.

Authors

Changjiang Cui¹, Zhifeng Ma¹, Hui Wan¹, Jianbo Gao¹, Baoliang Zhou²

Affiliations

¹ State Key Laboratory of Crop Genetics & Germplasm Enhancement, Collaborative Innovation Center for Modern Crop Production Co-sponsored By Province and Ministry, Nanjing Agricultural University, Nanjing, China.
² State Key Laboratory of Crop Genetics & Germplasm Enhancement, Collaborative Innovation Center for Modern Crop Production Co-sponsored By Province and Ministry, Nanjing Agricultural University, Nanjing, China. Electronic address: baoliangzhou@njau.edu.cn.

PMID: 36215791
DOI: 10.1016/j.plaphy.2022.09.029

Abstract

The alpha-ketoglutarate-dependent dioxygenase (AlkB) gene family plays an essential role in regulating plant development and stress response. However, the AlkB gene family is still not well understood in cotton. In this study, 40 AlkB genes in cotton and Arabidopsis are identified and classified into three classes based on phylogenetic analysis. Their protein motifs and exon/intron structures are highly conserved. Chromosomal localization and synteny analysis suggested that segmental or whole-genome duplication and polyploidization events contributed to the expansion of the cotton AlkB gene family. Furthermore, the AlkB genes showed dynamic spatiotemporal expression patterns and diverse responses to abiotic stresses. Among them, GhALKBH10 was down-regulated under various abiotic stresses and its subcellular expression was localized in cytoplasm and nucleus. Silencing GhALKBH10 in cotton increased antioxidant capacity and reduced cytoplasmic Na⁺ concentration, thereby improved the plant tolerance to salinity. Conversely, overexpression (OE) of GhALKBH10 in Arabidopsis markedly weakened the plant tolerance to salinity. The global m⁶A levels measured in VIGS and OE transgenic lines showed that they were significantly higher in TRV: GhALKBH10 plants (VIGS) than in TRV: 00 plants but significantly lower in OE plants than wild-type plants under salt stress, which could be considered as a potential m⁶A demethylase in cotton. Our results suggest that the GhALKBH10 gene negatively regulates salt tolerance in plants, which provides information of the cotton AlkB family and an understanding of GhALKBH10 function under salt condition as well as a new gene for salt-tolerant cotton breeding.

Keywords: AlkB; Cotton; Gene family, Salt stress; GhALKBH10.