protein
AP-1 complex subunit sigma-2
Gene
AP1S2
Organism
Homo sapiens(9606)
Length
157 aa
Mass
18,615 Da
AP-1 complex subunit sigma-2 (AP1S2) is a component of the clathrin-associated adaptor protein complex 1, which mediates protein sorting in the late-Golgi/trans-Golgi network and endosomes by recruiting clathrin to membranes and recognizing cargo sorting signals (UniProt: P56377). The protein functions in intracellular trafficking and membrane protein organization across multiple cellular compartments.
AP1S2 is associated with Pettigrew syndrome, an X-linked disorder characterized by intellectual disability, choreoathetosis, hydrocephalus, and seizures (UniProt: P56377). This link highlights the protein's importance in neurological function, particularly in developmental contexts.
AP1S2 is upregulated in Alzheimer's disease brain tissue. Human post-mortem AD brain compared to age-matched controls showed elevated AP1S2 levels across measured subcellular fractions, with a mean log2 fold-change of 1.03 (Chaparral AD proteomics). This upregulation suggests potential involvement in AD-related pathological processes, though the specific mechanistic contribution to neurodegeneration remains to be elucidated.
Generated from the curated entity record below. May contain errors — verify against source links.
Proteomics Evidence · AD
↑ Up in ADP3
+1.065
P2
+0.986
S2
not detected
S3
not detected
Mean log₂FC across detected fractions: +1.0256 (2 of 4 fractions detected)
Human post-mortem AD brain vs age-matched controls, TMT-labeled, 4 subcellular fractions (P2, P3, S2, S3), DDA proteomics.
Related Publications
Browse all →Tau molecular diversity contributes to clinical heterogeneity in Alzheimer's disease.
Dujardin Simon et al.Nature medicine2020PMID 32572268Deep Multilayer Brain Proteomics Identifies Molecular Networks in Alzheimer's Disease Progression.
Bai Bing et al.Neuron2020PMID 31926610A Multi-network Approach Identifies Protein-Specific Co-expression in Asymptomatic and Symptomatic Alzheimer's Disease.
Seyfried Nicholas T et al.Cell systems2017PMID 27989508Large-scale deep multi-layer analysis of Alzheimer's disease brain reveals strong proteomic disease-related changes not observed at the RNA level.
Johnson Erik C B et al.Nature neuroscience2022PMID 35115731Organization and regulation of gene transcription.
Cramer PatrickNature2019PMID 31462772
Function
Subunit of clathrin-associated adaptor protein complex 1 that plays a role in protein sorting in the late-Golgi/trans-Golgi network (TGN) and/or endosomes. The AP complexes mediate both the recruitment of clathrin to membranes and the recognition of sorting signals within the cytosolic tails of transmembrane cargo molecules
Disease associations
Pettigrew syndromePGS
An X-linked syndrome characterized by intellectual disability and additional highly variable features, including choreoathetosis, hydrocephalus, Dandy-Walker malformation, seizures, and iron or calcium deposition in the brain. Intellectual disability is characterized by significantly below average general intellectual functioning associated with impairments in adaptive behavior and manifested during the developmental period.
Sources
Last updated 5/8/2026, 6:32:27 AM