Research Paper

Molecular Mechanisms Underlying the Regulation of Anthocyanin Biosynthesis by the Transcription Factor CsMYB75-like-2 in Tea Plants (Camellia sinensis)

  • ZHOU Hui ,
  • CUI You ,
  • CHEN Wenjian ,
  • DU Yueyang ,
  • ZHANG Huan ,
  • SU Hongfeng ,
  • ZHANG Kaikai ,
  • ZHANG Lingyun
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  • 1. Guangdong Provincial Engineering Technology Research Center for Southern Specialty Tea, Guangzhou 510642, China;
    2. College of Horticulture, South China Agricultural University, Guangzhou 510642, China

Received date: 2025-06-11

  Revised date: 2025-07-06

  Online published: 2026-02-06

Abstract

Anthocyanins, as vital plant secondary metabolites, contribute to pigmentation, pollinator attraction and stress resistance, significantly impacting plant development. This study elucidated the regulatory role of the R2R3-MYB transcription factor CsMYB75-like-2 in anthocyanin biosynthesis in tea plants (Camellia sinensis), utilizing the anthocyanin-rich cultivar ‘Zijuan’ as the material. Phylogenetic analysis reveals that CsMYB75-like-2 belongs to the SG6 subfamily of anthocyanin-related transcription factors. CsMYB75-like-2 is expressed at higher levels in purple tea cultivars than in green ones and is specifically enriched in young tissues. Its coding sequence remains highly conserved across cultivars. Subcellular localization confirmed its residence in the nuclear membrane, and yeast assays demonstrated its function as a transcriptional activator. Shade treatment experiments showed a positive correlation between CsMYB75-like-2 expression, its downstream genes (CsDFR and CsFLS) as well as anthocyanin accumulation. However, unlike CsMYB75-like-1, CsMYB75-like-2 does not directly bind to or activate the key anthocyanin biosynthesis gene CsANS. Instead, it forms an interactive regulatory network with other MYB family members, including CsMYB308 and CsMYB114. These findings provided crucial insights into the molecular mechanisms governing anthocyanin biosynthesis in tea plants and offer valuable targets for breeding enhanced purple tea cultivars.

Cite this article

ZHOU Hui , CUI You , CHEN Wenjian , DU Yueyang , ZHANG Huan , SU Hongfeng , ZHANG Kaikai , ZHANG Lingyun . Molecular Mechanisms Underlying the Regulation of Anthocyanin Biosynthesis by the Transcription Factor CsMYB75-like-2 in Tea Plants (Camellia sinensis)[J]. Journal of Tea Science, 2026 , 46(1) : 20 -34 . DOI: 10.13305/j.cnki.jts.2026.01.001

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