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]
Overall distribution
Tissue specific distribution
Overall distribution
Tissue specific distribution
Gscore (Amp):
0.00
Gscore (Del):
0.00
Overall distribution
Tissue specific distribution
Mscore:
0.00
Overall
Tissue specific
Total fusion occurrence:
0
Overall
Tissue specific
Functional class:
Not specified
JensenLab PubMed score:
57.41 (Percentile rank: 64.67%)
PubTator score:
57.68 (Percentile rank: 70.07%)
Target development/druggability level:
TbioThese targets do not have known drug or small molecule activities that satisfy the activity thresholds detailed below AND satisfy one or more of the following criteria: 1) target is above the cutoff criteria for Tdark; 2) target is annotated with a Gene Ontology Molecular Function or Biological Process leaf term(s) with an Experimental Evidence code.
Tractability (small molecule):
N/A
Tractability (antibody):
Predicted Tractable - High confidenceTargets located in the plasma membrane; Targets with GO cell component terms plasma membrane or secreted
