2',3'-Cyclic-nucleotide 3'-phosphodiesterase
Protein-coding gene in the species Homo sapiens
From Wikipedia, the free encyclopedia
2′,3′-Cyclic-nucleotide 3'-phosphodiesterase (EC 3.1.4.37, CNPase, systematic name nucleoside-2′,3′-cyclic-phosphate 2′-nucleotidohydrolase) is an enzyme that in humans is encoded by the CNP gene.[5][6]
| 2′,3′-Cyclic-nucleotide 3'-phosphodiesterase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 3.1.4.37 | ||||||||
| CAS no. | 60098-35-3 | ||||||||
| Databases | |||||||||
| BRENDA | enzyme data | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | enzyme entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| Rhea | reactions | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
Reaction
CNPase catalyzes the following reaction:
- nucleoside 2′,3′-cyclic phosphate + H2O nucleoside 2′-phosphate
Function
CNPase is a myelin-associated enzyme that makes up 4% of total CNS myelin protein, and is thought to undergo significant age-associated changes.[7] It is named for its ability to catalyze the phosphodiester hydrolysis of 2',3'-cyclic nucleotides to 2'-nucleotides, though a cohesive understanding of its specific physiologic functions are still ambiguous.[8]
Structural studies have revealed that four classes of CNPases belong to one protein superfamily. CNPase's catalytic core consists of three alpha-helices and nine beta-strands. The proposed mechanism of CNPases phosphodiesterase catalytic activity is similar to the second step of the reaction mechanism for RNase A.[9]
CNPase is expressed exclusively by oligodendrocytes in the CNS, and the appearance of CNPase seems to be one of the earliest events of oligodendrocyte differentiation.[10] CNPase is thought to play a critical role in the events leading up to myelination.[11]
CNPase also associates with microtubules in brain tissue and FRTL-5 thyroid cells, and is reported to have microtubule-associated protein-like activity (MAP; see MAP2), being able to catalyze microtubule formation at low molar ratios. Deletion of the C-terminus of CNPase or phosphorylation abolish the catalytic activity of microtubule formation. CNPase can link tubulin to cellular membranes, and might be involved in the regulation cytoplasmic microtubule distribution.[12]
CNPase has also been demonstrated to inhibit the replication of HIV-1 and other primate lentiviruses by binding the retroviral Gag protein and inhibiting the genesis of nascent viral particles. Whether this is a biological function of CNPase or a coincidental activity remains unclear.[13]