Phylogenetic and Functional Analysis of CesA Genes in Cotton
Background: Cotton (Gossypium hirsutum) is widely distributed all over the world, and improving the quality of its fiber is one of the most important tasks in cotton breeding. Cotton fibers are primarily composed of cellulose, which is synthesized and regulated by cellulose synthase (CesAs). But the molecular mechanism of CesA genes in cotton was unclear. Results: In this study, the phylogenetic history and purifying selection of CesA genes were investigated along with their functions. CesA3
... functions. CesA3 and CesA6 are the two largest subgroups in G. arboreum, comprising 52.8% of the whole CesA family. These two CesA subgroups were then chosen for further research, and the results showed that they are highly differentiated in dicot groups. The two subgroups were also discriminated with the use of a Ka/Ks analysis. This indicated that they may play an important role in fiber development based on their unique phylogenetic status. Functional studies were subsequently conducted using the most purified genes (Gohir.A08G144300.1 in CesA3 subgroup). The silencing of Gohir.A08G144300.1 visibly inhibits the growth of cotton fiber, showing that it is critical for the growth of cotton fibers. Conclusions: The results presented here a target gene Gohir.A08G144300.1 based on the analysis of CesA gene members, and it is found that this gene was crucial to the growth of cotton fibers. This study provides more information for the understanding of the molecular mechanism of cotton fiber development.