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Optical Sectioning and Visualization of the Intervertebral Disc from Embryonic Development to Degeneration
Published on: July 8, 2021
Functional architecture of atrophins
Yiguo Shen1, Gena Lee1, Youngshik Choe1
1Gallo Center and the Department of Neurology, University of California at San Francisco, Emeryville, California 94608.
The Journal of Biological Chemistry
|December 8, 2006
Summary
Vertebrate genomes contain two Atrophin genes, Atrophin-1 and Atrophin-2. While Atrophin-1 is dispensable for development, Atrophin-2
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- Vertebrate genomes possess two Atrophin genes: Atrophin-1 (Atn1) and Atrophin-2 (Atn2).
- Atn2 locus encodes two protein isoforms: a full-length form and a short form.
- Atrophin-1 and Atrophin-2 interact, suggesting a functional partnership.
Purpose of the Study:
- To investigate the developmental role of Atrophin-1 by generating a null allele.
- To elucidate the distinct functional domains and regulatory activities of Atrophin gene products.
- To understand the requirement of Atrophin function in early embryonic development.
Main Methods:
- Generation of an Atrophin-1 null allele in vertebrates.
- Co-immunoprecipitation assays to assess protein interactions.
- Functional domain analysis of Atrophin-1, Atrophin-2 long form, and Atrophin-2 short form.
Main Results:
- Atrophin-1 function was found to be dispensable for vertebrate development.
- The long form of Atrophin-2 possesses unique transcriptional repression activity essential for embryogenesis.
- Atrophin-1 and the short form of Atrophin-2 exhibit potent transcriptional activation capabilities.
Conclusions:
- Atrophins function as bifunctional transcriptional regulators, integrating both activation and repression activities.
- The specific transcriptional repression activity of the long Atrophin-2 isoform is critical for normal embryogenesis.
- Differential activities of Atrophin isoforms highlight complex regulatory roles in development.
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