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Hox specificity unique roles for cofactors and collaborators
Richard S Mann1, Katherine M Lelli, Rohit Joshi
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
Current Topics in Developmental Biology
|August 5, 2009
Summary
Hox proteins regulate gene expression through specific DNA elements. Understanding these cis-regulatory elements reveals flexibility in Hox function, crucial for animal evolution.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- Hox proteins are critical transcription factors with well-defined in vivo functions.
- The molecular mechanisms of Hox-mediated gene regulation are not fully understood.
- Understanding transcription factor function requires analyzing their cis-regulatory elements.
Purpose of the Study:
- To review concepts of Hox protein gene regulation.
- To analyze validated Hox-regulated cis-regulatory elements.
- To identify generalizations in Hox-binding site characteristics and cofactor/collaborator roles.
Main Methods:
- Literature review of Hox protein gene regulation.
- Analysis of curated Hox cis-regulatory elements and binding sites.
- Examination of five X-ray crystal structures of Hox-cofactor-DNA complexes.
Main Results:
- Identified generalizations in Hox-binding sites within cis-regulatory elements.
- Distinguished between Hox cofactors (DNA binding) and collaborators (regulation sign/strength).
- Structural analysis revealed significant flexibility in Hox protein regulatory mechanisms.
Conclusions:
- Hox protein gene regulation is highly flexible.
- Cofactors and collaborators play distinct roles in Hox-mediated transcription.
- This flexibility likely contributes to Hox proteins' role in animal morphological evolution.
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