Identification of key genes related to flowering by transcriptome of flowering and nonflowering Prunella vulgaris.

Prunella vulgaris L. have high medicinal and ornamental values. It blooms in summer and then quickly withers, and there is no research on the regulatory mechanisms of flowering-related genes. Therefore, in this study, the flowering (leaves and spicas) and nonflowering (leaves) parts of P. vulgaris were sequenced with an Illumina HiSeq 4000, and 187 387 transcripts were obtained using Trinity software package. A total of 10 158 differentially expressed genes (DEGs) were found in the leaves of flowering and nonflowering P. vulgaris, with 6 294 upregulated genes and 3 864 downregulated genes. DEGs in leaves of flowering and nonflowering P. vulgaris were mainly annotated for metabolic processes (4 207) in Gene Ontology (GO) and ribosomal pathways (416) in Kyoto Encyclopedia of Genes and Genomes (KEGG). Screening of this set of genes yielded 50 flowering-related unigenes homologous to Arabidopsis genes involved in multiple regulatory pathways related to plant flowering, including autonomous, vernalization, gibberellin, and age pathways. In addition, there are significant differences in the expressions of genes related to flowering, such as PvFLC, PvSOC1, and PvFY, as well as genes involved in plant hormone signal transduction and sugar metabolism. The accuracy and reliability of the transcriptome results were verified by quantitative real-time RT-qPCR analysis of PvGA20OX, PvSVP, PvELF3, PvCRY1, and PvSOC1. Thus, we speculate that the flowering of P. vulgaris is regulated by certain genes related to the flowering regulation pathway and sugar and hormone metabolism pathways. Analysis of the P. vulgaris transcriptome will provide a basis for revealing its flowering mechanism. [ABSTRACT FROM AUTHOR]