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Updated: May 12, 2026
11:02
Chromatin Immunoprecipitation Assay for Tissue-specific Genes using Early-stage Mouse Embryos
Published on: April 29, 2011
The MyoD DNA binding domain contains a recognition code for muscle-specific gene activation
R L Davis1, P F Cheng, A B Lassar
1Department of Genetics, Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|March 9, 1990
Summary
The MyoD basic region is crucial for DNA binding and muscle gene activation. Swapping this region prevents muscle program activation, even with DNA binding capability.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- The myogenic determination gene MyoD plays a key role in muscle development.
- A specific 60 amino acid domain of MyoD is known to be essential for its function.
Purpose of the Study:
- To identify the specific region within the MyoD domain responsible for sequence-specific DNA binding and myogenic conversion.
- To investigate the role of the helix-loop-helix (HLH) motif and the upstream basic region in MyoD's function.
Main Methods:
- Site-directed mutagenesis was used to replace specific regions of the MyoD gene.
- In vitro DNA binding assays were performed to assess sequence-specific binding.
- Transfection assays using C3H10T1/2 cells were conducted to evaluate myogenic conversion and muscle-specific gene activation.
Main Results:
- A highly basic region upstream of the HLH motif is essential for MyoD's in vitro DNA binding.
- Replacing helix1, helix2, or the loop of MyoD with analogous sequences from Drosophila T4 achaete-scute protein did not affect DNA binding or muscle gene activation.
- Substitution of the MyoD basic region with sequences from E12 or T4 achaete-scute proteins allowed DNA binding but abolished muscle-specific gene activation.
Conclusions:
- The MyoD basic region contains a recognition code critical for muscle-specific gene activation.
- Sequence-specific DNA binding alone is insufficient to trigger the muscle development program; the basic region's specific sequence is required.
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