Abstract
Basic-helix-loop-helix (bHLH) class transcription factors bind DNA as hetero- and homodimers. In murine myogenic cells the HLH network includes multiple members of the E protein, MyoD, and Id families; changes in the network characterize muscle determination and differentiation and have been proposed as causal for these developmental transitions. To test the importance of HLH partner choice in these cellular decisions, we have designed a strategy in which the identity of a bHLH dimer is specified by joining two monomers via a flexible polypeptide linker. A MyoD ∼ E47 polyprotein avidly bound the same DNA target as its unlinked counterpart, but, unlike intermolecular dimers that are very sensitive to inhibition by Id, MyoD ∼ E47 was resistant to Id challenge. In cells MyoD ∼ E47 acted as a dominant positive myogenic factor, capable of initiating myogenic determination and also substantially bypassing negative regulation of differentiation by serum growth factors.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
