SHUH SHERAZI, M SHAFIQ, H AHMED, J AHMAD, M HAMMAD, A SANAM, M REHAN, MT TUFAIL, Q HAYYAT
Pathogenesis-related gene PR1 acts as an essential element in the plant defensive mechanism and is made during the process of systemic acquired resistance (SAR) and salicylic-induced signaling. The genome-wide analysis of the PR1 gene in Pisum sativum has been conducted to analyze the functionality, composition, and evolutionary status of this gene. Based on the fact that CAP (Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1) domain, fifteen PsPR1 genes were identified. Complete CAP domain has been found on these proteins, which ensures that all belong to the PR1 family. There is a mild difference in the size of protein, the molecular mass, as well as the point of isoelectric activity showed by the physicochemical study. On the other hand, subcellular localization predictions revealed that there is predominant extracellular targeting, with the secretory nature of PR-1 proteins, in multiple cellular compartments. The Fabaceae family has a lineage-specific increase of PR-1 genes, according to phylogenetic research with several dicot species. This suggests functional conservation with known Arabidopsis thaliana PR-1 homologs involved in SAR. The majority of PsPR1 genes are either intron-less or have a single intron, supporting fast transcriptional activation during stress, according to conserved motif and gene structure analyses that revealed strong evolutionary conservation. Strong purifying selection was shown by Ka/Ks analysis of duplicated gene pairs, highlighting PR-1 genes' physiological importance in pea defence. Numerous cis-regulatory regions linked to hormone signalling, stress response, and transcription factor binding were found by promoter analysis, suggesting intricate regulatory control. PsPR1 genes were found to be distributed unevenly by chromosomal mapping, with tandem duplication being the main cause of the substantial clustering on chromosome 1. Tandem and segmental duplication events both contributed to the formation of the gene family, according to synteny analysis. PsPR1.1, PsPR1.3, and PsPR1.9 were found to be significantly regulated genes by expression profiling during heat stress, especially in the heat-tolerant cultivar Akra Chaitra. Overall, this study identifies intriguing possibilities for enhancing heat stress resilience and offers a solid foundation for comprehending the functional evolution and stress-responsive activities of PR-1 genes in Pisum sativum.