关键词: 白花泡桐, CPP基因家族, 胁迫, 表达分析, 高值化利用

Abstract:

Objective: This study systematically analyzed the molecular characteristics of the CPP gene family in P. fortunei and their functions in stress resistance, aiming to provide theoretical basis and genetic resources for the creation of stress-tolerant Paulownia germplasm and its high-value utilization. Method: Based on the whole-genome data of P. fortunei, the bioinformatics, transcriptomics, and molecular biology approaches were comprehensively used to systematically identify members of the PfCPP gene family, and analyze in-depth their physicochemical properties, gene structures, evolutionary relationships, cis-acting elements, and expression patterns in response to biotic (phytoplasma infection) and abiotic (drought, salt) stresses. RT-qPCR was used to verify the expression trends of key genes, and explore their potential functions by combining subcellular localization and protein-protein interaction prediction. Result: A total of 7 PfCPP genes (PfCPP1–PfCPP7) were identified, which were classified into 3 subfamilies and unevenly distributed on 6 chromosomes. Cis-acting element analysis showed that these genes were enriched in elements related to light response, hormone regulation, and stress response. Synteny analysis indicated that segmental duplication was the main driver of the family expansion. Expression profile analysis revealed that PfCPP members exhibited specific expression divergence under different stresses: phytoplasma infection significantly induced the upregulation of PfCPP2/3/4/5/7; under drought stress, PfCPP1–4 were upregulated while PfCPP5–7 were downregulated; only PfCPP7 was significantly induced under salt stress. RT-qPCR results verified the reliability of the transcriptomic data. Subcellular localization showed that PfCPP4 was localized in the nucleus. Protein-protein interaction prediction and molecular docking results suggested that PfCPP4/7 might exert regulatory functions by interacting with MYB-like transcription factors. Conclusion: This study has systematically identified the PfCPP gene family in P. fortunei and revealed their structural characteristics and evolutionary rules. The differential expression patterns of PfCPP genes under various stresses indicate their important regulatory roles in Paulownia stress responses. They may form regulatory networks by interacting with MYB proteins to coordinately regulate Paulownia growth, development, and stress adaptation.

Key words: Paulownia fortunei, CPP gene family, stress, expression analysis, high-value utilization