Comparison of endogenous and overexpressed MyoD shows enhanced binding of physiologically bound sites

作者：Yao Zizhen; Fong Abraham P; Cao Yi; Ruzzo Walter L; Gentleman Robert C; Tapscott Stephen J^*

来源：Skeletal Muscle, 2013, 3(1): 8.

DOI：10.1186/2044-5040-3-8

• Transcription factor
• Overexpressed
• MyoD
• c-Myc
• ChIP-seq

Background: Transcription factor overexpression is common in biological experiments and transcription factor amplification is associated with many cancers, yet few studies have directly compared the DNA-binding profiles of endogenous versus overexpressed transcription factors.
Methods: We analyzed MyoD ChIP-seq data from C2C12 mouse myotubes, primary mouse myotubes, and mouse fibroblasts differentiated into muscle cells by overexpression of MyoD and compared the genome-wide binding profiles and binding site characteristics of endogenous and overexpressed MyoD.
Results: Overexpressed MyoD bound to the same sites occupied by endogenous MyoD and possessed the same E-box sequence preference and co-factor site enrichments, and did not bind to new sites with distinct characteristics.
Conclusions: Our data demonstrate a robust fidelity of transcription factor binding sites over a range of expression levels and that increased amounts of transcription factor increase the binding at physiologically bound sites.

• 出版日期2013