Evolutionary Relationships and Divergence of Filamin Gene Family Involved in Development and Stress in Cotton ( Gossypium hirsutum L.).

Filamin protein is characterized by an N-terminal actin-binding domain that is followed by 24 Ig (immunoglobulin)-like repeats, which act as hubs for interactions with a variety of proteins. In humans, this family has been found to be involved in cancer cell invasion and metastasis and can be involved in a variety of growth signal transduction processes, but it is less studied in plants. Therefore, in this study, 54 gene family members from 23 plant species were investigated and divided into two subfamilies: FLMN and GEX2. Subcellular localization showed that most of the gene family members were located in the cell membrane. A total of 47 gene pairs were identified, most of which were whole-genome copies. Through the analyses of -acting elements, expression patterns and quantitative fluorescence, it was found that and are mainly expressed in the reproductive organs of upland cotton, and their interacting proteins are also related to the fertilization process, whereas and were related to stress. Thus, it is speculated that two genes of the GEX2 subfamily ( and ) may be involved in the reproductive development of cotton and may affect the fertilization process of cotton. This study provides a theoretical basis for the further study of the cotton gene family.