Identification of CPP genes in quinoa and functional characterization of CqCPP09 under drought stress

The Cysteine-rich polycomb-like gene encodes key transcription factors involved in abiotic stress responses. Therefore, we conducted a comprehensive analysis of the quinoa genome to determine the function of CPP protein in quinoa. In this study, 11 CPP genes were identified in quinoa, and duplication events showed that they produced 7 pairs of fragment duplications. Phylogenetic analysis divided CPP genes into two subfamilies based on their gene structures and conserved motifs, which were consistent with their classification on the phylogenetic tree. Additionally, a total of 33 elements related to light, hormone regulation, tissue-specific expression patterns, and abiotic stress response were found in the promoter region, including stress elements such as drought defense and stress response elements. Finally, the expression pattern of CqCPP genes under abiotic stress was studied by combining transcriptome data with qRT-PCR. The results demonstrated that all 11 CqCPP genes responded differently to drought and salt stress. In particular, CqCPP09 gene. In addition, the CqCPP09 gene was overexpressed in Arabidopsis thaliana. The value of Pn, Tr, and Gs, the content of SPAD and Proline, the activity of Superoxide Dismutase, Peroxidase and Catalase in the overexpressed lines under drought stress was significantly higher than those in the wild type. This study provides new insights into the evolution and function of the CPP TF family during quinoa growth and development, and these findings offer important clues for further analyzing drought stress response functions.

The online version contains supplementary material available at 10.1007/s12298-026-01748-w.