Nucleolar release of Hand1 acts as a molecular switch to determine cell fate

  title={Nucleolar release of Hand1 acts as a molecular switch to determine cell fate},
  author={David Michael John Martindill and Catherine A. Risebro and Nicola Smart and Maria Del Mar Franco-Viseras and Carla O. Rosario and Carol Jane Swallow and James W. Dennis and Paul Richard Riley},
  journal={Nature Cell Biology},
The bHLH transcription factor Hand1 is essential for placentation and cardiac morphogenesis in the developing embryo. Here we implicate Hand1 as a molecular switch that determines whether a trophoblast stem cell continues to proliferate or commits to differentiation. We identify a novel interaction of Hand1 with a protein that contains an I-mfa (inhibitor of myogenic factor) domain that anchors Hand1 in the nucleolus where it negatively regulates Hand1 activity. In the trophoblast stem-cell… 

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