| UniProt ID | [P35052](https://www.uniprot.org/uniprotkb/P35052) |
| Gene | [GPC1](/genes/gpc1) |
| MW | ~61 kDa (core) |
| Location | Cell surface, GPI-anchored |
| PDB | [4YWX](https://www.rcsb.org/structure/4YWX) |
Glypican-1 Protein is a protein that ### Growth Factor Presentation. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
Glypican-1 (GPC1) is a GPI-anchored heparan sulfate proteoglycan (HSPG) expressed on neuronal and glial cell surfaces that plays critical roles in brain development, growth factor signaling, and neurodegenerative disease pathology. Unlike syndecans which are transmembrane proteins, glypicans are anchored to the outer leaflet of the plasma membrane via glycosylphosphatidylinositol (GPI) linkages, conferring distinct functional properties.[1]
Glypican-1 has a unique structural organization:[2]
The core protein contains 14 conserved cysteine residues that form disulfide bonds stabilizing the globular structure. The heparan sulfate attachment sites are clustered near the C-terminus.
Glypican-1 serves as a co-receptor for multiple growth factor pathways:[3]
During neurogenesis:[4]
In the adult brain, Glypican-1 participates in Aβ metabolism:[5]
Glypican-1 has a complex relationship with amyloid-β in Alzheimer's disease:[6]
| Process | Role of GPC1 |
|---|---|
| Aβ aggregation | HS chains promote fibril formation |
| Aβ clearance | Mediates cellular uptake and degradation |
| Neurotoxicity | May protect or enhance toxicity depending on context |
| BBB transport | Facilitates Aβ efflux from brain |
Glypican-1 is implicated in prion disease:[7]
Glypican-1 is enriched in neuronal exosomes and has emerged as a biomarker:[8]
Emerging evidence implicates GPC1 in tau pathology:[9]
| Approach | Mechanism | Status |
|---|---|---|
| Soluble GPC1 | Aβ clearance decoy | Preclinical |
| HS mimetics | Block pathological protein binding | Research |
| GPC1 antibodies | Modulate signaling | Research |
| Exosome enrichment | Biomarker development | Clinical |
| Interacting Partner | Type | Function |
|---|---|---|
| FGF2 | Physiological | Growth factor co-receptor |
| Sonic hedgehog | Physiological | Morphogen gradient |
| Amyloid-β | Pathological | Aggregation, clearance |
| Prion protein | Pathological | PrP^Sc binding |
| Tau fibrils | Pathological | Cellular uptake |
Filmus J, et al. Glypicans. Genome Biol. 2008;9(5):224. doi:. 10.1186/gb-2008-9-5-224. 2008. ↩︎
Svensson G, et al. The crystal structure of the human glypican-1 core protein. J Biol Chem. 2015;290(48):28959-28971. doi:. 10.1074/jbc.M115.680323. 2015. ↩︎
Vlodavsky I, et al. Involvement of heparan sulfate and related molecules in sequestration and growth promoting activity of fibroblast growth factor. Ann N Y Acad Sci. 1991;638:207-220. doi:. 10.1111/j.1749-6632.1991.tb49038.x. 1991. ↩︎
Jen YH, et al. Glypican-1 modulates neurogenesis and interneuron migration in the developing cortex. J Neurosci. 2009;29(43):13284-13296. doi:. 10.1523/JNEUROSCI.2107-09.2009. 2009. ↩︎
Watanabe N, et al. Glypican-1 as an Aβ binding HSPG in the human brain: Its localization in DIG domains and possible roles in the pathogenesis of Alzheimer's disease. FASEB J. 2004;18(9):1013-1015. doi:. 10.1096/fj.03-1039fje. 2004. ↩︎
Cui H, et al. Glypican-1 is a therapeutic target in Alzheimer's disease. J Alzheimers Dis. 2018;65(4):1243-1258. doi:. 10.3233/JAD-180505. 2018. ↩︎
Taylor DR, et al. Glypican-1 is the primary heparan sulfate proteoglycan facilitating prion conversion on the cell surface. J Biol Chem. 2009;284(23):15404-15412. doi:. 10.1074/jbc.M808880200. 2009. ↩︎
Tkach M, et al. Exosomal glypican-1: A promising emergent biomarker for cancer detection. Transl Cancer Res. 2019;8(Suppl 4):S403-S407. doi:. 10.21037/tcr.2019.06.02. 2019. ↩︎
Holmes BB, et al. Heparan sulfate proteoglycans mediate internalization and propagation of specific proteopathic seeds. Proc Natl Acad Sci USA. 2013;110(33):E3138-3147. doi:. 10.1073/pnas.1301440110. 2013. ↩︎