Comprehensive genome-wide analysis of DUF668 gene family in potato reveals roles in growth and stress responses.

The DUF668 gene family, distinguished by a plant-specific conserved domain, is significantly involved in growth and stress responses. An extensive genome-wide study of the DUF668 gene family in potato (Solanum tuberosum L.) was conducted. A total of 11 DUF668s (StDUF668-1 to StDUF668-11) were recognized and analysed for their physicochemical characteristics, chromosomal distribution, gene structures, conserved motif profiles, secondary and tertiary structures and evolutionary relationships. The StDUF668s exhibited diverse structures, with intron-exon variations contributing to their functional diversity. The analysis of promoter sequences revealed multiple cis-acting regulatory elements related to phytohormones, stress responses, and developmental processes, indicating their potential modulatory roles. Expression profiling was conducted across various potato tissues and under different hormonal and stress conditions which demonstrated that StDUF668s play a role in crucial biological processes, involving abiotic and biotic stress responses. Furthermore, qRT-PCR-based expression profiling in response to salt and osmotic stress conditions validated that StDUF668s are involved in abiotic stress responses. Protein-protein interaction and miRNA targeting analyses highlighted the molecular pathways associated with the functions of DUF668s in potato. This study advances our understanding of the DUF668 gene family and provides a valuable resource for future research aimed at improving potato stress tolerance and growth.