Comprehensive profiling of Bcl-2-associated athanogene (BAG) genes and their genetic potential role under cold stress in Cotton

Bcl-2-associated athanogene (BAG) gene family is important in stress tolerance and death regulation in plants. Cotton (Gossypium hirsutum) is an important cash crop with strong functional significance, while the BAG gene family in cotton has been little studied. Remains largely unexplored. Of these, the genome-wide identification and characterization of BAG genes were performed in Gossypium hirsutum, Gossypium barbadense, Gossypium raimondii, and Gossypium arboreum in this study. In G. hirsutum, G. barbadense, G. raimondii, and G. arboreum, there were 30, 32, 12, and 11 BAG genes found, respectively. Phylogenetic classification groupgrouped these genes into five classes (A–E), depending on their evolutionary relatedness with the BAG genes from other plant species. Investigation of the gene structures and expression patterns of BAG proteins indicated conserved domain architectures, gene motifs, and subcellular localizations among Gossypium species. Within tetraploid species, whole-genome and segmental duplications were determined to be the main contributors to BAG gene expansion, while diploid progenitors had few gene duplication events. Comparative sequence approaches and analyses of conserved motifs revealed jagged evolutionary conservation of the BAG domain indicating their possible functional roles in stress response and programmed cell death. Detailed expression profiling under abiotic stress conditions (drought, salt, and cold) showed that several BAG genes significantly differentially expressed which indicating their participation in adaptation mechanisms to stress conditions. In addition, the identification of essential cis-regulatory factors in the promoter regions suggested potential regulation by environmental changes. BAG gene family Structure, evolutionary relationship and expression pattern in cotton in response to different stresses study with predictable implications. Deciphering how the BAG gene functions at a molecular and evolutionary scale will help guide future research into genetic engineering approaches aimed at enhancing cotton tolerance to environmental stressors.