Genome-wide Identification and Function Analysis of HMAD Gene Family in Cotton (Gossypium Spp.)

Background: Soil salinized and heavy metal toxicity has become a major threat to sustainable crop production worldwide. Previous studies revealed that halophytes were supposed to tolerate other stress including heavy metal toxicity. Though HMAD (heavy-metal-associated domain) was reported to play various important functions in different plants, little is known in Gossypium . Results: : A total of 169 G. hirsutum genes were identified belonging to the HMAD gene family and divided into five classes. Additionally, 84, 76 and 159 HMAD genes were identified in each G. arboreum, G. raimondii and G. barbadense , respectively. Furthermore, conserved sequence analysis found the conserved catalytic center containing an anion binding (CXXC) box. The HMAD gene family showed a differential expression levels among different tissues and developmental stages in G. hirsutum with the different cis-elements and transcription factor binding sites (TFBS) for abiotic stress. Conclusions: : Current study provides important information about HMAD genes under salt-stress in Gossypium genome, which would be useful to understand its putative functions in different species of cotton.