Genome-wide identification and characterization of FORMIN genes in cotton: Implications for abiotic stress tolerance

Background

Formins are highly conserved proteins with multiple domains that play an important role in the interaction with microfilaments and microtubules and thus regulate actin organisation and cytoskeletal dynamics. Despite their importance in plant development and response to stress, the study of FORMIN (FH) genes in cotton, an important fibre crop, remains limited. The genetic diversity of these genes is critical for improving the adaptability of cotton to environmental stress, which is a major challenge for cotton breeding programmes aimed at improving abiotic stress tolerance.

Results

Through comprehensive bioinformatics approaches, we identified 46, 50 and 27 putative FH genes in Gossypium hirsutum, G. barbadense and their diploid ancestors G. arboreum and G. raimondii, respectively. A phylogenetic analysis classified these genes into five subfamilies and revealed evolutionary relationships to Arabidopsis thaliana. Syntenic and collinear analyses showed that genomic duplications in cotton have driven the expansion of the FH gene family. Structural analysis showed significant variations in sequence length and conserved motifs. Promoter analysis revealed several cis-acting elements associated with growth, stress response and hormonal signalling. Protein-protein interaction predictions suggest involvement in hormone signalling, cytoskeletal regulation and cell wall dynamics. Differential expression of G. hirsutum FH (GhFH) genes in different cotton tissues under drought and osmotic stress was confirmed by qRT-PCR.

Conclusion

This study provides new insights into the functional diversity and evolutionary dynamics of FH genes in cotton and emphasises their potential role in improving abiotic stress tolerance. By identifying key regulatory genes involved in stress adaptation, this research contributes to the development of more resilient cotton varieties through targeted breeding strategies. The results underline the importance of genetic diversity in enabling cotton breeding programmes to overcome the challenges posed by abiotic stress.