Related Experiment Video
Updated: Apr 27, 2026

Annotation of Plant Gene Function via Combined Genomics, Metabolomics and Informatics
Published on: June 17, 2012
The transcription factor CaMYB108a negatively regulates anthocyanin and other flavonoid biosynthesis in chili pepper
Qiaoyun He1, Shucan Liu2, Chenyuan Wang2
1Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518124, China.
Abstract:
Fruit color is a key horticultural trait that determines the economic value of chili pepper (Capsicum annuum L.), which is predominantly governed by the accumulation of flavonoid compounds, especially anthocyanins. The R2R3-MYB transcription factor subfamily plays a crucial role in regulating anthocyanin and flavonoid biosynthesis, yet its specific regulatory mechanisms in chili peppers remain largely elusive. In this study, using the known anthocyanin-related light-responsive factor CaHY5 as bait, we identified it interacting with R2R3-MYB protein through yeast two-hybrid screening, designated CaMYB108a. Phylogenetic and genomic analyses supported its classification within the MYB family. Functional validation demonstrated that CaMYB108a acts as a negative regulator of anthocyanin accumulation and total flavonoid compounds in chili pepper fruits. Overexpression of CaMYB108a significantly suppressed the expression of key anthocyanin biosynthetic structural genes, reduced anthocyanin accumulation, and decreased total flavonoid and quercetin contents. Conversely, silencing CaMYB108a markedly enhanced the expression of anthocyanin-related genes, promoted anthocyanin accumulation, and increased total flavonoid content and quercetin levels, whereas luteolin showed a slight decrease, indicating differential regulation across distinct branches of the flavonoid pathway. Further investigation revealed that CaMYB108a directly binds to the promoter regions of key anthocyanin biosynthetic genes CaCHI, CaF3'5'H, and CaDFR, repressing their transcription. This study uncovers the negative regulatory role of CaMYB108a in anthocyanin and flavonoid accumulation in chili pepper fruits and provides novel insights and a genetic target for improving fruit coloration.
More Related Videos
11:33Investigating Interactions Between Histone Modifying Enzymes and Transcription Factors in vivo by Fluorescence Resonance Energy Transfer
Published on: October 14, 2022
07:55Luciferase Complementation Imaging Assay in Nicotiana benthamiana Leaves for Transiently Determining Protein-protein Interaction Dynamics
Published on: November 20, 2017
Related Concept Videos
Adaptations that Reduce Water Loss
Transcription Attenuation in Prokaryotes
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Biological Clocks and Seasonal Responses
C4 Pathway and CAM
C4 Pathway
The C4 pathway is used by plants such as...
Gene Regulation During Sporulation
Cell Specific Gene Expression