Objective Plant AT-rich sequence and zinc-binding (PLATZ) transcription factors are plant-specific, zinc-dependent DNA-binding proteins that play a role in regulating plant growth and environmental stress responses. To clarify the characteristics of the PLATZ family members in peanut (Arachis hypogaea), this study screened and analyzed the expression of the identified PLATZ gene family members in peanut.

Method Using peanut genome data, the PLATZ gene family members in peanut were identified, and bioinformatics methods were used to systematically analyze the physicochemical properties, phylogenetic trees, protein conservative motifs, cis-acting elements, and protein interactions of this gene family members. And the expression patterns of peanut PLATZ genes under salt and drought stress were analyzed using RT-qPCR.

Result A total of 13 AhPLATZ genes were identified in peanuts, which are unevenly distributed across 7 chromosomes. The AhPLATZ proteins range from 194 to 260 amino acids in length, with molecular weights between 22.00 and 29.49 kD, instability indices between 43.42 and 73.46, aliphatic indices between 47.46 and 83.92, and protein hydrophilicity between-1.094 and-0.345, indicating that they are all hydrophilic proteins. The AhPLATZ proteins are primarily localized in the nucleus and chloroplasts. Based on phylogenetic relationships, the AhPLATZ genes were categorized into 4 groups, with genes within the same group typically having similar motif compositions and numbers of exons or introns. The collinearity results suggest that the expansion of AhPLATZ gene members was achieved through gene duplication after diversification. Additionally, the promoter regions of AhPLATZ include various cis-acting elements associated with stress response and hormone regulation. The results of the RT-qPCR analysis indicate that AhPLATZ4, AhPLATZ5, and AhPLATZ11 exhibit significantly induced expression under salt stress, while AhPLATZ4 and AhPLATZ5 actively respond to drought stress.

Conclusion Thirteen members of the PLATZ gene family have been identified in peanuts, among which AhPLATZ4 and AhPLATZ5 actively respond to both salt stress and drought stress. These findings provide a basis for further functional investigations of the AhPLATZ genes in peanuts.