Genome-wide identification and expression analysis of the chlorophyll a/b binding protein gene family in oilseed (Brassica napus L.) under salt stress conditions

Abstract

To elucidate the functions and molecular mechanisms of BnLhc gene family members in Brassica napus under different exogenous hormones and abiotic stress, we identified 57 BnLhc gene family members from the entire genome of B. napus variety ZS11 using Arabidopsis Lhc protein as a seed sequence combined with phyll A-B binding protein PF00504. We performed comprehensive analyses including physicochemical property analysis, structural analysis, phylogenetic relationship analysis, homology relationship analysis, protein interaction network analysis, microRNA-target gene interaction analysis and GO enrichment analysis. Additionally, based on transcriptome data, we investigated response patterns of BnLhc genes to various exogenous stress conditions. Comparative evaluation between non-salt (NS:0) and salt-treated (TS: 1) rapeseed plants revealed significant inhibition in leaf chlorophyll content, biomass (W), leaf area (LA), root surface area (RA), as well as chloroplasts and roots under salt treatment. Furthermore, qPCR was employed to assess the relative expression levels of BnLhc genes associated with salt tolerance. Our findings indicate that while BnLhcs were upregulated in leaves upon exposure to salt signals suggesting their potential involvement in enhancing rape's resistance to salt stress through ion redistribution processes; they were downregulated in roots. This study provides valuable insights into the functionality and molecular genetic mechanisms underlying the role BnLhc gene family