Genome-Wide Identification and Functional Prediction of Phytochelatin Synthase Gene in Upland Cotton

Objective] Heavy metal stress rise advertise effects on growth and development in plant, from which phytochelatin synthase (PCS) plays key roles to protect plant cells. This article will present studies on the gene amount, structure, distribution and features. Method] PCS gene family in cotton are analyzed based on completely global genome sequence cotton species including Gossypium hirsutum ((AD)1), G. raimondii (D5) and G. arboreum (A2), for further understanding of those genes and protein family features. In this study, we conducted the analysis involving in identification on PCS family members, special protein domain comparison, polygenetic analysis, gene structure prediction and Cysteine survey. Result] 2, 2 and 4 PCS genes were identified out in G. raimondii (D5), G. arboreum (A2) and G. hirsutum ((AD)1), respectively. All these 8 PCS genes had phytochelatin and phytochelatin_C domains and strictly conserved amino acid residues related to catalytic activity. Cotton PCS protein family members could be divided into 2 sub-group, and these members belongs to sub-group I or sub-group II are close todicotyledon or nematode, respectively. What’s more, there are some difference in both gene structure and Cys distribution between those 2 sub-groups. Less integrity of exons in PCS genes in G. raimondii, comparing to G. hirsutum and G. arboreum. Conclusion] Comparing to sub-group II, the PCS genes from sub-group I should be higher catalytic activity. G. hirsutum and its donor G. arboreum probably are more heavy metal tolerant than G. raimondii. Based on the results, this research will provide some insights on further functional study.