Identification of Stress-Responsive Transcription Factors Interacting with Cysteine Desulfurase through Co-expression Network Analysis under Drought, Heat, and Salinity Conditions in Potato (Solanum tuberosum)

Abstract

Cysteine desulfurases are essential enzymes involved in sulfur metabolism, redox regulation, and hydrogen sulfide (H₂S) signalling, especially under abiotic stress conditions. This study aimed to explore the gene networks associated with a cysteine desulfurase gene (PGSC0003DMT400078713) in Solanum tuberosum exposed to drought, heat, and salinity. A subset of RNA-Seq data (SRA029323) were analysed using the Tuxedo pipeline on the Galaxy platform, and log₂(FC) values were used to assess gene co-expression. A total of 2,397 genes showed strong positive correlation (r ≥ 0.90) with the target gene, including 201 transcription factors and kinases identified from the iTAK database. Functional annotation revealed that the top co-expressed genes are involved in oxidative stress response, signal transduction, and mitochondrial respiration. Notably, a cytochrome-c oxidase involved in proton transport and copper binding (PGSC0003DMT400080385) and a putative membrane protein (PGSC0003DMT400065426) were highly upregulated under drought and heat stress, suggesting their role in stress adaptation. Conversely, some uncharacterized genes (e.g., PGSC0003DMT400096412 and PGSC0003DMT400022675) were strongly downregulated under salinity and drought. Network analysis positioned the cysteine desulfurase gene as a central hub linking multiple stress-responsive TF and kinase families, including AP2/ERF, MYB, NAC, and bHLH. These findings contribute to a better understanding of the molecular mechanisms behind abiotic stress responses in potato and may guide future breeding or genetic engineering strategies aimed at improving stress resilience in crops. © This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY SA) license