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Nicotinamide adenine dinucleotide: beyond a redox coenzyme
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA. hl379@cornell.edu
Organic & Biomolecular Chemistry
|November 21, 2007
Summary
ADP-ribosylation, a key enzymatic reaction involving nicotinamide adenine dinucleotide (NAD+), impacts numerous biological processes. This review covers ADP-ribosyltransferases like PARPs, sirtuins, and CD38, detailing their functions and mechanisms.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- ADP-ribosylation is a crucial post-translational modification regulating diverse cellular functions.
- Nicotinamide adenine dinucleotide (NAD+) serves as the substrate for ADP-ribosylation reactions.
- Various enzymes, known as ADP-ribosyltransferases, catalyze these modifications.
Purpose of the Study:
- To provide a comprehensive review of ADP-ribosyltransferases.
- To elucidate the enzymatic reactions, mechanisms, structures, and biological roles of these enzymes.
- To highlight the significance of NAD+ in ADP-ribosylation processes.
Main Methods:
- Literature review of ADP-ribosyltransferases.
- Analysis of enzymatic reaction mechanisms.
- Examination of protein structures.
- Compilation of biological functions.
Main Results:
- Detailed overview of key ADP-ribosyltransferases: PARPs, ARTs, sirtuins, tRNA 2'-phosphotransferases, and ADP-ribosyl cyclases (CD38, CD157).
- Explanation of diverse catalytic mechanisms and structural features.
- Summary of the wide-ranging biological processes influenced by these enzymes.
Conclusions:
- ADP-ribosylation is a versatile enzymatic modification with profound biological implications.
- Understanding ADP-ribosyltransferases is essential for deciphering cellular regulation and disease mechanisms.
- This review consolidates current knowledge on these critical enzymes and their functions.
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