Genome-wide investigation of HD-ZIP gene family and functional characterization of BnaHDZ149 and BnaHDZ22 in salt and drought response in Brassica napus L

• Published in: Plant science (Limerick) 2024-09, Vol.346, p.112130, Article 112130
• Main Authors: Fang, Yujie, Wang, Lu, Liu, Kuan, Wu, Han, Zheng, Yuqian, Duan, Yujing, Feng, Shanshan, Wang, Youping
• Format: Article
• Language: English
• Subjects: Brassica napus; Brassica napus - genetics; Brassica napus - physiology; drought; Drought stress; Droughts; family; Gene Expression Regulation, Plant; genes; Genes, Plant; genetically modified organisms; Genome, Plant; HD-ZIP; Multigene Family; Phylogeny; plant development; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified - genetics; polyethylene glycol; rapeseed; Salt stress; Salt Tolerance - genetics; species; Stress, Physiological - genetics; transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; transcriptomics; water stress
• ISSN: 0168-9452; 1873-2259; 1873-2259
• DOI: 10.1016/j.plantsci.2024.112130

HD-ZIP proteins comprise a plant-specific transcription factor family, which play pivotal roles in plant development and adaptation to ever-changing environment. Although HD-ZIP family members have been identified in some plant species, so far our knowledge about HD-ZIP genes in rapeseed is still limited. In this study, 178 Brassica napus HD-ZIP (BnaHDZ) family members were identified in the rapeseed genome. The phylogenetic relationship, chromosomal locations, intron-exon structures, motif composition, and expression patterns of the BnaHDZ members were analyzed. The BnaHDZ family can be phylogenetically divided into four categories (Ⅰ, Ⅱ, Ⅲ and Ⅳ). Genome-wide transcriptome analysis revealed that most of the HD-ZIP I members respond to at least one abiotic stress. Two closely homologous stress-responsive HD-ZIP Ⅰ genes, BnaHDZ22 and BnaHDZ149, were identified to be involved in drought and salt responses, and selected for further functional characterization. Overexpressing BnaHDZ149 in rapeseed increased salt sensitivity of the transgenic plants, whereas overexpressing BnaHDZ22 increased sensitivity of the transgenic plants to polyethylene glycol (PEG)-simulated drought stress. This research provides not only a comprehensive landscape of BnaHDZ genes, but also a theoretical basis for elucidating the molecular mechanism of the abiotic stress responses of the HD-ZIP family in rapeseed. •A total of 178 HD-ZIP genes belonging to four categories (Ⅰ, Ⅱ, Ⅲ and Ⅳ) were systematically identified in B. napus.•Two closely homologous stress-responsive HD-ZIP Ⅰ genes, BnaHDZ22 and BnaHDZ149, were functionally characterized.•BnaHDZ149 was identified as a negative regulator of salt tolerance in B. napus.•Overexpression of BnaHDZ22 increased sensitivity to osmotic stress of transgenic rapeseed.