Genome-Wide Analysis of the DUF1664 Family Genes in Peanut (Arachis hypogaea) and Functional Validation of AhDUF1664-1A

The Domains of Unknown Functions 1664 (DUF1664) genes are a class of genes with unknown functions, and their roles in abiotic stresses responses have not yet been reported. Using the hidden Markov model (HMM) profile of DUF1664 (PF07889) obtained from the Pfam database, along with Arabidopsis thaliana DUF1664 family protein sequences as reference, and verifying complete DUF1664 domains with the NCBI CD-Search online tool, seven DUF1664 family members were identified in the peanut (Arachis hypogaea) genome, designated as AhDUF1664-1A through AhDUF1664-4. Promoter analysis revealed that cis-acting elements in AhDUF1664 genes are associated with growth and development, stress responses, and plant hormone signaling, and these genes exhibit relatively conserved motifs. Functional validation showed that ectopic expression of AhDUF1664-1A enhanced tolerance to salt and drought stresses in Arabidopsis thaliana by modulating the expression of ABA signaling-related genes. Our findings identify the AhDUF1664 gene family in peanut and provide a basis for further investigation into the biological functions of these genes.