Previous results indicated that in grapevine （Vitis vinifera）, regulation of the flavonoid pathway genes by MYB transcription factors depends on their interaction with basic helix-loop-helix proteins （bHLHs）. The ...Previous results indicated that in grapevine （Vitis vinifera）, regulation of the flavonoid pathway genes by MYB transcription factors depends on their interaction with basic helix-loop-helix proteins （bHLHs）. The present study describes the first functional characterization of a bHLH factor from grapevine named VvMYC1. This transcription factor is phylogenetically related to Arabidopsis bHLH proteins, which participate in the control of flavonoid biosynthesis and epidermal cell fate. Transient promoter and yeast two-hybrid assays demonstrated that VvMYC1 physically interacts with MYB5a, MYB5b, MYBA1/A2, and MYBPA1 to induce promoters of flavonoid pathway genes involved in anthocyanin and/ or proanthocyanidin （PA） synthesis. Additionally, transient promoter assays revealed that VvMYC1 is involved in feedback regulation of its own expression. Transcript levels of VvMYC1 during berry development correlate with the synthesis of anthocyanins and PAs in skins and seeds of berries, suggesting that VvMYC1 is involved in the regulation of anthocyanins and PA synthesis in these organs. Likewise, transient expression of VvMYC1 and VvMYBA1 induces anthocyanin synthesis in grapevine suspension cells. These results suggest that VvMYCl is part of the transcriptional cascade controlling antho- cyanin and PA biosynthesis in grapevine.展开更多
Derived from neural stem cells(NSCs)and progenitor cells originated from the neuroectoderm,the nervous system presents an unprecedented degree of cellular diversity,interwoven to ensure correct connections for propaga...Derived from neural stem cells(NSCs)and progenitor cells originated from the neuroectoderm,the nervous system presents an unprecedented degree of cellular diversity,interwoven to ensure correct connections for propagating information and responding to environ-mental cues.NSCs and progenitor cells must integrate cell-intrinsic programs and environmental cues to achieve production of appropriate types of neurons and glia at appropriate times and places during develop-ment.These developmental dynamics are reflected in changes in gene expression,which is regulated by transcription factors and at the epigenetic level.From early commitment of neural lineage to functional plas-ticity in terminal differentiated neurons,epigenetic regulation is involved in every step of neural develop-ment.Here we focus on the recent advance in our un-derstanding of epigenetic regulation on orderly genera-tion of diverse neural cell types in the mammalian nervous system,an important aspect of neural devel-opment and regenerative medicine.展开更多
文摘Previous results indicated that in grapevine （Vitis vinifera）, regulation of the flavonoid pathway genes by MYB transcription factors depends on their interaction with basic helix-loop-helix proteins （bHLHs）. The present study describes the first functional characterization of a bHLH factor from grapevine named VvMYC1. This transcription factor is phylogenetically related to Arabidopsis bHLH proteins, which participate in the control of flavonoid biosynthesis and epidermal cell fate. Transient promoter and yeast two-hybrid assays demonstrated that VvMYC1 physically interacts with MYB5a, MYB5b, MYBA1/A2, and MYBPA1 to induce promoters of flavonoid pathway genes involved in anthocyanin and/ or proanthocyanidin （PA） synthesis. Additionally, transient promoter assays revealed that VvMYC1 is involved in feedback regulation of its own expression. Transcript levels of VvMYC1 during berry development correlate with the synthesis of anthocyanins and PAs in skins and seeds of berries, suggesting that VvMYC1 is involved in the regulation of anthocyanins and PA synthesis in these organs. Likewise, transient expression of VvMYC1 and VvMYBA1 induces anthocyanin synthesis in grapevine suspension cells. These results suggest that VvMYCl is part of the transcriptional cascade controlling antho- cyanin and PA biosynthesis in grapevine.
基金supported by grants from the National Natural Science Foundation of China(Grant No.2012CB966701)the Ministry of Science and Technology of the People’s Republic of China.
文摘Derived from neural stem cells(NSCs)and progenitor cells originated from the neuroectoderm,the nervous system presents an unprecedented degree of cellular diversity,interwoven to ensure correct connections for propagating information and responding to environ-mental cues.NSCs and progenitor cells must integrate cell-intrinsic programs and environmental cues to achieve production of appropriate types of neurons and glia at appropriate times and places during develop-ment.These developmental dynamics are reflected in changes in gene expression,which is regulated by transcription factors and at the epigenetic level.From early commitment of neural lineage to functional plas-ticity in terminal differentiated neurons,epigenetic regulation is involved in every step of neural develop-ment.Here we focus on the recent advance in our un-derstanding of epigenetic regulation on orderly genera-tion of diverse neural cell types in the mammalian nervous system,an important aspect of neural devel-opment and regenerative medicine.
