Genome-Wide Identification of Wheat KNOX Gene Family and Functional Characterization of TaKNOX14-D in Plants

• Published in: International journal of molecular sciences Vol. 23; no. 24; p. 15918
• Main Authors: Li, Song, Yao, Yaxin, Ye, Wenjie, Wang, Shaoyu, Zhang, Chao, Liu, Shudong, Sun, Fengli, Xi, Yajun
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14.12.2022; MDPI
• Subjects: Abscisic acid; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Barley; Chromosomes; cold stress; Cytokinins; D gene; Exons; Gene expression; Gene Expression Regulation, Plant; Genes; Genome, Plant; Genomes; High resistance; Hormones; Introns; KNOX expression pattern; KNOX gene; KNOX gene family; leaf development; Leaves; Low temperature resistance; mechanical damage; Multigene Family; Phylogeny; Plant Proteins - genetics; Plant Proteins - metabolism; Proteins; Soybeans; Stress, Physiological - genetics; Triticum; Wheat; KNOX gene family; cold stress; wheat; mechanical damage; KNOX expression pattern; leaf development
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms232415918

The KNOX genes play important roles in maintaining SAM and regulating the development of plant leaves. However, the genes in wheat are still not well understood, especially their role in abiotic stress. In this study, a total of 36 KNOX genes were identified, and we demonstrated the function of the gene under mechanical injury and cold stress. Thirty-six genes were divided into two groups, and thirty-four genes were predicted to be located in the nucleus by Cell-PLoc. These genes contained five tandem duplications. Fifteen collinear gene pairs were exhibited in wheat and rice, one collinear gene pair was exhibited in wheat and Arabidopsis. The phylogenetic tree and motif analysis suggested that the gene appeared before C3 and C4 diverged. Gene structure showed that the numbers of exons and introns in gene are different. Wheat genes showed different expression patterns during the wheat growth phase, with seven genes being highly expressed in the whole growth period. These seven genes were also highly expressed in most tissues, and also responded to most abiotic stress. Eleven TaKNOX genes were up-regulated in the tillering node during the leaf regeneration period after mechanical damage. When treating the wheat with different hormones, the expression patterns of TaKNOX were changed, and results showed that ABA promoted expression and seven genes were up-regulated under cytokinin and auxin treatment. Overexpression of the gene in could increase the leaf size, plant height and seed size. This gene overexpression in also increased the compensatory growth capacity after mechanical damage. Overexpression lines also showed high resistance to cold stress. This study provides a better understanding of the TaKNOX genes.