JA Regulates Caffeine Biosynthesis in Tea Leaf for Resistance Against Fungal Infection and Antagonises With GA to Balance the Defence-Growth Trade-Off via CsDELLA-JAZ-MYC2-MYB184-TCS1 Module.

ABSTRACT: Caffeine is a defensive alkaloid primarily accumulated in tea leaves to defend against pathogens. But the regulatory mechanism for caffeine biosynthesis in response to fungal infection and the trade-off between specialised metabolite and plant growth remain elusive. Here, we report that jasmonic acid (JA)-regulated CsMYB184 is the key for caffeine biosynthesis in tea leaves. Exogenous MeJA promoted caffeine biosynthesis in tea leaves and enhanced the resistance against fungal pathogens. JASMONATE ZIM-domain proteins (JAZs) interacted with CsMYB184 to repress CsMYB184 transactivation of TCS1. Meanwhile, JA effector CsMYC2 directly bound to and activated CsMYB184 transcription, but inhibited plant growth by directly modulating GA inactivation through gibberellin 2-oxidase 4 (CsGA2ox4). By co

SUBMITTER: Ye Z 

PROVIDER: S-EPMC12665076 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature