Catechins, the key active components in tea, are known for their protective effects against conditions like diabetes, cancer, and cardiovascular diseases. However, their biosynthesis is highly sensitive to environmental factors, particularly phosphate (Pi) availability, which is often scarce in the soils where tea is grown.
This deficiency can adversely affect tea quality by disrupting the accumulation of secondary metabolites. Given these challenges, there is an urgent need to understand the molecular mechanisms governing catechin production under varying nutrient conditions.
Conducted by scientists at the Zhejiang Academy of Agricultural Sciences and published in Horticulture Research, a study explores the complex interplay between phosphate signaling and jasmonate (JA) pathways in tea plants.
Researchers identified two key transcription factors, CsPHR1 and CsPHR2 (Phosphate Starvation Response, PHR), involved in phosphate signaling, and CsJAZ3 (JAZ, Jazmonate Zim Domain), a repressor in the jasmonate pathway. Together, these elements regulate catechin biosynthesis in response to nutrient levels and hormonal signals, providing new insights into the genetic control of tea quality.
The research demonstrates that phosphate deficiency activates critical genes in catechin biosynthesis through CsPHR1 and CsPHR2, boosting the expression of CsANR1 (anthocyanidin reductase, ANR) and CsMYB5c (Myeloblastosis, MYB), which are pivotal in catechin production. Additionally, CsSPX1, a phosphate pathway repressor, was found to inhibit the action of CsPHR1 and CsPHR2, fine-tuning the response to phosphate availability.
