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The chemical biology of NAD⁺ regulation in axon degeneration.

ABSTRACT: During axon degeneration, NAD⁺ levels are largely controlled by two enzymes: nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) and sterile alpha and toll interleukin motif containing protein 1 (SARM1). NMNAT2, which catalyzes the formation of NAD⁺ from NMN and ATP, is actively degraded leading to decreased NAD⁺ levels. SARM1 activity further decreases the concentration of NAD⁺ by catalyzing its hydrolysis to form nicotinamide and a mixture of ADPR and cADPR. Notably, SARM1 knockout mice show decreased neurodegeneration in animal models of axon degeneration, highlighting the therapeutic potential of targeting this novel NAD⁺ hydrolase. This review discusses recent advances in the SARM1 field, including SARM1 structure, regulation, and catalysis as well as the identification of the first SARM1 inhibitors.

SUBMITTER: Icso JD

PROVIDER: S-EPMC10084848 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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The chemical biology of NAD+ regulation in axon degeneration.

Icso Janneke D JD Thompson Paul R PR

Current opinion in chemical biology 20220701

During axon degeneration, NAD+ levels are largely controlled by two enzymes: nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) and sterile alpha and toll interleukin motif containing protein 1 (SARM1). NMNAT2, which catalyzes the formation of NAD+ from NMN and ATP, is actively degraded leading to decreased NAD+ levels. SARM1 activity further decreases the concentration of NAD+ by catalyzing its hydrolysis to form nicotinamide and a mixture of ...[more]

PMID: 35780654

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