Transcriptome sequencing and screening of genes related to sex determination of Trichosanthes kirilowii Maxim.

Trichosanthes kirilowii Maxim. (TK) is a dioecious plant in the Cucurbitaceae for which different sexes have separate medicinal uses. In order to study the genes related to sex determination, transcriptome sequencing was performed on flower buds and leaves of male and female plants using the high-throughput sequencing technology. A total of 145,975 unigenes and 7110 DEGs were obtained. There were 6776 DEGs annotated to 1234 GO terms and enriched to 18 functional groups, including five biological processes related to sugar metabolism. KEGG pathway analysis indicated genes involved in hormone transduction, hormone synthesis and carbohydrate metabolism. The sex determination genes of TK are different from known sex determination mechanisms (ACS11, ACS7(2), WIP1). Many DEGs of TK are involved in reproductive organ formation, hormone signal transduction and regulatory networks. In combination with the previous study of sex differentiation of Cucurbitaceae, the results of GO, KEGG and the expression of related genes in male and female plants, 18 candidate genes for sex determining of TK were screened from 151 hormone-related differentially expressed genes. The genes included MYB80, MYB108 and MYB21 of the MYB family, CER1, CBL, ABCB199, SERK1 and HSP81-3. The results provide a foundation for the study of sex differentiation in TK.