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Preparation of Living Isolated Vertebrate Photoreceptor Cells for Fluorescence Imaging
Published on: June 22, 2011
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Cobalamin's (Vitamin B12) Surprising Function as a Photoreceptor.
Zhuo Cheng1, Haruki Yamamoto1, Carl E Bauer1
1Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN 47405, USA.
Trends in Biochemical Sciences
|May 25, 2016
Summary
Vitamin B12 (cobalamin) has a new regulatory role. Light absorption can link B12 to proteins, influencing gene expression and potentially other cellular functions.
Area of Science:
- Biochemistry
- Molecular Biology
- Bioinformatics
Background:
- Cobalamin (Vitamin B12) is a vital cofactor for numerous enzymes.
- Many proteins with B12-binding domains have unknown functions.
- Emerging evidence links B12 to non-enzymatic regulatory roles.
Purpose of the Study:
- To explore novel regulatory functions of Vitamin B12.
- To identify new classes of proteins that bind B12.
- To investigate the potential for light-regulated B12 interactions.
Main Methods:
- Bioinformatics analysis of protein domains.
- Literature review of B12-protein interactions.
- Analysis of B12-dependent gene regulation.
Main Results:
- Identified B12-binding domains in transcription factors, photoreceptors, kinases, and oxygen sensors.
- Demonstrated light-induced covalent linkage of B12 to transcription factors.
- Showed B12's role in regulating gene expression.
Conclusions:
- Vitamin B12 possesses a newly identified regulatory function beyond enzymatic catalysis.
- Light absorption can modulate B12-protein interactions, impacting cellular processes.
- Further research into light-sensitive B12-binding proteins is warranted.
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