Comparative Transcriptomic Analyses of Chlorogenic Acid Biosynthesis Pathways in Diploid and Triploid Camellia sinensis

Abstract

Chlorogenic acid (CGA), as a kind of depside in plants, has a variety of beneficial effects on human health, which also plays an important role in helping plants resist a variety of stresses. Therefore, the biosynthetic pathway of CGA has been studied in many plants, however, the synthesis of CGA has not been well elucidated in Camellia sinensis. In our research, different CGA levels were detected between triploid tea variety „Qianfu 4‟ and diplont tea variety „Qianmei 419‟ using HPLC and the CGA content in triploid Camellia sinensis was greater than that in diploid Camellia sinensis. Transcriptome sequencing for diploid and triploid Camellia sinensis was employed to explore genes associated with CGA biosynthesis. Finally, 154,097 unigenes were obtained in total, of which 891 may be related to the biosynthesis of CGA. Furthermore, differentially expressed genes (DEGs) were screened between diploid and triploid Camellia sinensis, 32 DEGs were discovered to be related to CGA biosynthesis, including sixteen phenylalanine ammonia lyase (PAL) genes, three 4-coumarate coenzyme A ligase (4CL) genes, nine cinnamate 4-Hydroxylase (C4H) genes, four Hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HQT/HCT), and two hundred and twenty-one TFs including eighty-eight ERFs, forty-one bZIPs, forty-two MYBs and fifty WRKYs, which may also play an important role in the biosynthesis of CGA. Our results will lay the foundation for further exploration of the biosynthesis of CGA and revealing the related regulatory network in Camellia sinensis. © 2021 Friends Science Publishers