P-selectin

Selectin P (granule membrane protein 140kDa, antigen CD62)
PDB rendering based on pdb 1gsr.
Available structures PDB 1FSB, 1G1Q, 1G1R, 1G1S, 1HES, 1KJD
Identifiers
Symbols	SELP; CD62; CD62P; FLJ45155; GMP140; GRMP; LECAM3; PADGEM; PSEL
External IDs	OMIM: 173610 MGI: 98280 HomoloGene: 2260 GeneCards: SELP Gene
Gene Ontology Molecular function • lipopolysaccharide binding • glycoprotein binding • protein binding • sugar binding • heparin binding • sialic acid binding • fucose binding • glycosphingolipid binding • eukaryotic cell surface binding • calcium-dependent protein binding • oligosaccharide binding Cellular component • extracellular space • membrane fraction • soluble fraction • plasma membrane • plasma membrane • integral to plasma membrane • external side of plasma membrane • platelet dense granule membrane • platelet alpha granule membrane • platelet alpha granule membrane Biological process • platelet degranulation • positive regulation of leukocyte migration • regulation of cellular extravasation • inflammatory response • cell adhesion • heterophilic cell-cell adhesion • leukocyte cell-cell adhesion • blood coagulation • positive regulation of platelet activation • response to organic cyclic compound • platelet activation • response to lipopolysaccharide • positive regulation of cell adhesion • blood vessel morphogenesis • defense response to Gram-negative bacterium • leukocyte migration • leukocyte tethering or rolling Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	6403	20344
Ensembl	ENSG00000174175	ENSMUSG00000026580
UniProt	P16109	Q32MF1
RefSeq (mRNA)	NM_003005.3	NM_011347.2
RefSeq (protein)	NP_002996.2	NP_035477.1
Location (UCSC)	Chr 1: 169.56 – 169.6 Mb	Chr 1: 166.05 – 166.08 Mb
PubMed search	[1]	[2]

P-selectin is a cell adhesion molecule (CAM) on the surfaces of activated endothelial cells, which line the inner surface of blood vessels, and activated platelets. In unactivated endothelial cells, it is stored in granules called Weibel-Palade bodies, and α-granules in unactivated platelets.

Other names for P-selectin include CD62P, Granule Membrane Protein 140 (GMP-140), and Platelet Activation-Dependent Granule to External Membrane Protein (PADGEM). It was first shown to be found in endothelial cells in 1989.

Function

P-selectin plays an essential role in the initial recruitment of leukocytes (white blood cells) to the site of injury during inflammation. When endothelial cells are activated by molecules such as histamine or thrombin during inflammation, P-selectin moves from an internal cell location to the endothelial cell surface.

Thrombin is one trigger which can stimulate endothelial-cell release of P-selectin and recent studies suggest an additional Ca²⁺-independent pathway involved in release of P-selectin. ^[1]

Ligands for P-selectin on eosinophils and neutrophils are similar sialylated, protease-sensitive, endo-beta-galactosidase-resistant structures, clearly different than those reported for E-selectin, and suggest disparate roles for P-selectin and E-selectin during recruitment during inflammatory responses. ^[2]

P-selectin is also very important in the recruitment and aggregation of platelets at areas of vascular injury. In quiescent platelet, P-selectin is located on the inner wall of α-granules. Platelet activation (through agonists such as thrombin, Type II collagen and ADP) results in "membrane flipping" where the platelet releases α- and dense granules and the inner walls of the granules are exposed on the outside of the cell. The P-selectin then promotes platelet aggregation through platelet-fibrin and platelet-platelet binding.

P-selectin attaches to the actin cytoskeleton through anchor proteins that are still poorly characterized.

See also

• Selectin

Footnotes

1. ^ Cleator, JH; Zhu, WQ; Vaughan, DE; Hamm, HE (April 2006). "Differential regulation of endothelial exocytosis of P-selectin and von Willebrand factor by protease-activated receptors and cAMP". Blood 107 (7): 2736–44. doi:10.1182/blood-2004-07-2698. PMC 1895372. PMID 16332977. 16332977. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1895372. 
2. ^ Wein, M; Sterbinsky, SA; Bickel, CA; Schleimer, RP; Bochner, BS (1995). "Comparison of human eosinophil and neutrophil ligands for P-selectin: ligands for P-selectin differ from those for E-selectin". Am J Respir Cell Mol Biol. 12 (3): 315–9. PMID 7532979. 

Further reading

• Ryan US, Worthington RE (1992). "Cell-cell contact mechanisms". Curr. Opin. Immunol. 4 (1): 33–7. doi:10.1016/0952-7915(92)90120-4. PMID 1375831. 
• Bajorath J, Stenkamp R, Aruffo A (1994). "Knowledge-based model building of proteins: concepts and examples". Protein Sci. 2 (11): 1798–810. doi:10.1002/pro.5560021103. PMC 2142283. PMID 7505680. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2142283. 
• Varki NM, Varki A (2002). "Heparin inhibition of selectin-mediated interactions during the hematogenous phase of carcinoma metastasis: rationale for clinical studies in humans". Semin. Thromb. Hemost. 28 (1): 53–66. doi:10.1055/s-2002-20564. PMID 11885026. 
• Furie B, Furie BC (2004). "Role of platelet P-selectin and microparticle PSGL-1 in thrombus formation". Trends in molecular medicine 10 (4): 171–8. doi:10.1016/j.molmed.2004.02.008. PMID 15059608. 
• Cambien B, Wagner DD (2004). "A new role in hemostasis for the adhesion receptor P-selectin". Trends in molecular medicine 10 (4): 179–86. doi:10.1016/j.molmed.2004.02.007. PMID 15059609. 
• Chen M, Geng JG (2006). "P-selectin mediates adhesion of leukocytes, platelets, and cancer cells in inflammation, thrombosis, and cancer growth and metastasis". Arch. Immunol. Ther. Exp. (Warsz.) 54 (2): 75–84. doi:10.1007/s00005-006-0010-6. PMID 16648968. 

External links

• MeSH P-Selectin