Aliases for GP1BB Gene
External Ids for GP1BB Gene
Previous GeneCards Identifiers for GP1BB Gene
Platelet glycoprotein Ib (GPIb) is a heterodimeric transmembrane protein consisting of a disulfide-linked 140 kD alpha chain and 22 kD beta chain. It is part of the GPIb-V-IX system that constitutes the receptor for von Willebrand factor (VWF), and mediates platelet adhesion in the arterial circulation. GPIb alpha chain provides the VWF binding site, and GPIb beta contributes to surface expression of the receptor and participates in transmembrane signaling through phosphorylation of its intracellular domain. Mutations in the GPIb beta subunit have been associated with Bernard-Soulier syndrome, velocardiofacial syndrome and giant platelet disorder. The 206 amino acid precursor of GPIb beta is synthesized from a 1.0 kb mRNA expressed in plateletes and megakaryocytes. A 411 amino acid protein arising from a longer, unspliced transcript in endothelial cells has been described; however, the authenticity of this product has been questioned. Yet another less abundant GPIb beta mRNA species of 3.5 kb, expressed in nonhematopoietic tissues such as endothelium, brain and heart, was shown to result from inefficient usage of a non-consensus polyA signal in the neighboring upstream gene (SEPT5, septin 5). In the absence of polyadenylation from its own imperfect site, the SEPT5 gene produces read-through transcripts that use the consensus polyA signal of this gene. [provided by RefSeq, Dec 2010]
GeneCards Summary for GP1BB Gene
GP1BB (Glycoprotein Ib Platelet Beta Subunit) is a Protein Coding gene. Diseases associated with GP1BB include Bernard-Soulier Syndrome, Type C and Velocardiofacial Syndrome. Among its related pathways are Formation of Fibrin Clot (Clotting Cascade) and Response to elevated platelet cytosolic Ca2+. GO annotations related to this gene include transmembrane signaling receptor activity. An important paralog of this gene is GP9.
UniProtKB/Swiss-Prot for GP1BB Gene
Gp-Ib, a surface membrane protein of platelets, participates in the formation of platelet plugs by binding to von Willebrand factor, which is already bound to the subendothelium.