RESUMO
Objective: To clone and analyze the coding region of gibberellin 20-oxidase (GA20ox) gene of Panax quinquefolium in seed dormancy and germination process. Methods: According to P. quinquefolium seeds transcriptome annotation, one transcript coding of GA20ox was obtained by comparative analysis of nine related unigenes. The full-length cDNA of PqGA20ox was determined by using RT-PCR method. Then the bioinformatic analysis of this gene and encoded protein was performed. The expression level of PqGA20ox in the roots, stems, leaves, and several seed dormancy periods was detected by real time fluorescent quantitative PCR (RT-qPCR). Results: Bioinformatic analysis showed that PqGA20ox contained 1092 bp and encoded 363 amino acids. PqGA20ox encoded protein had neither transmembrane nor signal peptide. The expression level of PqGA20ox was higher in the inset periods of morphological and physiological dormancy than that in the other periods based on RT-qPCR analysis. Conclusion: The PqGA20ox gene is cloned for the first time, and will provide a foundation for the dormancy release molecular mechanism of P. quinquefolium.