Integrative gene duplication and genome-wide analysis characterize Peroxin11 gene family in wheat

Abstract

Peroxisomes are essential organelles for plant development and stress adaptation, yet the Peroxin11 (PEX11) gene family that mediates peroxisome proliferation remains uncharacterized in wheat (Triticum aestivum L.), a key polyploid cereal. This study presents the first comprehensive genome-wide identification and integrative analysis of the wheat PEX11 genes (TaPEX11), identifying 12 loci encoding 13 protein isoforms due to alternative splicing at one locus. Chromosomal mapping revealed uneven distribution, while protein analyses confirmed a conserved Pfam05648 domain with multiple transmembrane helices; some TaPEX11 members showed divergent features suggestive of specialized roles. Phylogenetic and synteny analyses indicated family expansion through segmental duplications under strong purifying selection. Promoter analysis uncovered diverse cis‑elements associated with hormone signalling, development, and abiotic stress responses. Using RNA‑seq data and qRT‑PCR, I demonstrate that distinct TaPEX11 genes are inducible under drought, with higher expression in the tolerant genotype Masr‑3 compared to the sensitive Sakha‑94. This transcriptional response was associated with increased catalase activity and indicators of oxidative stress response in Masr‑3. Co‑expression network and Gene Ontology analyses linked TaPEX11 genes to photosynthesis, gluconeogenesis, and peroxisomal homeostasis. Overall, the findings highlight the evolutionary diversification and genotype‑specific regulation of wheat PEX11 genes under drought and provides candidates genes and regulatory elements for future functional studies and breeding programs targeting drought tolerance.