Biotech Updates

PtrMYB57 Transcription Factors Negatively Regulate Anthocyanin and Proanthocyanidin Synthesis in Poplar

May 31, 2017

Previous studies have identified that R2R3-MYB transcription factors are involved in anthocyanin and proanthocyanidin (PA) biosynthesis in poplar (Populus sp.). Researchers from various universities in China now report the identification and characterization of PtrMYB57. PtrMYB57 was found to encode R2R3 MYB protein localized in the nucleus and is expressed in mature leaves.

Transgenic poplar overexpressing PtrMYB57 exhibited a reduction in anthocyanin and PA accumulation compared to wild types. In contrast, high anthocyanin and PA levels were observed in Ptrmyb57 mutants. Furthermore, assays revealed that the PtrMYB57 transcription factor interacts with bHLH131 (bHLH) and PtrTTG1 (WDR) to form the MBW complex and binds to the flavonoid gene promoters, leading to inhibition of the promoters.

These results suggest that PtrMYB57 negatively regulates anthocyanin and PA biosynthesis in poplar.

For more on this study, read the article in Plant Cell Reports.