title: NPEP Protein
description: NPEP (Puromycin-Sensitive Aminopeptidase) - Puromycin-sensitive aminopeptidase (NPEP) is a cytosolic metallopeptidase that hydrolyzes N-terminal...
tags: kind:protein, section:proteins, state:published
| Gene | [NPEP](/proteins/npep) |
|---|---|
| UniProt | Q11011 |
| PDB Structures | 4OMU, 4P0Z |
| Molecular Weight | 99.4 kDa |
| Subcellular Localization | Cytoplasm, nucleus |
| Protein Family | M1 family, zinc metallopeptidases |
NPEP (Puromycin-Sensitive Aminopeptidase) is a cytosolic metallopeptidase that hydrolyzes N-terminal amino acids from peptide substrates. It belongs to the family of zinc-dependent aminopeptidases and plays essential roles in protein turnover, antigen processing, and regulation of bioactive peptides[1].
NPEP is widely expressed throughout the body with significant activity in the brain. In the central nervous system, it is localized in neurons and glial cells, where it participates in the degradation of proteins and peptides involved in synaptic transmission and neuroprotection. Its high activity in neural tissues reflects its importance in normal brain function[2].
The enzymatic activity of NPEP is specific for neutral amino acids at the N-terminus of peptides. It can degrade various neuroactive peptides including enkephalins, dynorphins, and substance P, thereby modulating pain perception, reward pathways, and stress responses. This broad substrate specificity makes NPEP a key regulator of peptidergic signaling in the brain[3].
In neurodegenerative diseases, NPEP has been implicated in several processes:
Alzheimer's disease: NPEP participates in the degradation of amyloid-beta peptides and may contribute to their clearance from the brain. Altered NPEP activity has been reported in AD brain tissue, suggesting a potential role in amyloid pathology[4].
Parkinson's disease: NPEP may be involved in the metabolism of alpha-synuclein and other proteins that aggregate in PD. Some studies suggest its activity is modulated in affected brain regions[5].
Amyotrophic lateral sclerosis (ALS): Changes in NPEP expression have been observed in ALS models, potentially affecting protein homeostasis and motor neuron survival[6].
Therapeutic modulation of NPEP activity is being explored. Inhibitors of NPEP have been investigated for their potential effects on peptide metabolism, while enhancers might boost protein clearance mechanisms relevant to neurodegenerative disease. Additionally, NPEP's role in antigen processing makes it relevant to neuroinflammation in chronic brain disorders[7].
NPEP (Puromycin-Sensitive Aminopeptidase) is a M1 family, zinc metallopeptidases protein with a molecular weight of approximately 99.4 kDa. The protein localizes to cytoplasm, nucleus.
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