Genome-Wide Identification and Functional Investigation of () Genes in Cotton.

ACO is one of the rate-limiting enzymes in the biosynthesis of ethylene, and it plays a critical role in the regulation of plant growth and development. However, the function of genes in cotton is not well studied. In this study, a total of 332 , 187 , and were identified in , , and , respectively. Gene duplication analysis showed that whole-genome duplication (WGD) and tandem duplication were the major forces driving the generation of cotton genes. In the promoters of , there were cis-acting elements responding to stress, phytohormones, light, and circadian factors, indicating the possible involvement of in these processes. Expression and co-expression analyses illustrated that most were not only widely expressed in various tissues but also coexpressed with other genes in response to salt and drought stress. overexpression in promoted flowering and increased salt tolerance. These results provide a comprehensive overview of the genes of cotton and lay the foundation for subsequent functional studies of these genes.