|CD42d||GP5 (glycoprotein V platelet), GPV (platelet glycoprotein)|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Lineage Restricted Molecule|
Type 1 glycoprotein
|82 / 82|
|CD42d expression is restricted on platelets and megakaryocytes.|
|MOLECULAR FAMILY NAME: Belongs to the mucin family.|
CD42d is a single-pass type-1 glycoprotein. It contains a 504 aa N-terminal extracellular domain which contains 14 leucine-rich sequences flanked by consensus flanking sequences of 22 aa, a thrombin cleavage site and cleavage sites for other physiological relevant proteases such as calpain and 8 potential N-glycosylation sites and may have 2-3 O-glycosylation sites in the region close to the membrane, a 24 aa transmembrane domain and a 16 aa cytoplamsic domain. CD42d belongs to the mucin family which is part of the leucine-rich repeat (LRR) family. It forms a non-covalent complex with CD42a, ba and cb.
POST-TRANSCRIPTIONAL MODIFICATION: No information.
There are 8 potential N-glycosylation sites and, possibly, in the region near to the membrane, 2 or 3 O-glycosylation sites.
|CD42 complex binds von Willebrand factor the thrombin.|
LIGANDS AND MOLECULES ASSOCIATED WITH CD42d
|CD42d combines with CD42a, CD42b and CD42c to form a CD42 complex, which functions as a receptor for von Willebrand factor. The receptor mediates the adhesion of platelets to injured vascular surfaces in the arterial circulation, a critical initiating event in homostasis. The complex mediates adhesion of platelets to subendothelial matrices, which are exposed upon damage to the endothelium, at high shear rates. It also amplifies the platelet response to thrombin during platelet activation where thrombin is involved. |
The CD42a-d complex serves as receptor for von Willebrand factor (vWf) and thrombin.
DISEASE RELEVANCE AND FUNCTION OF CD42d IN INTACT ANIMAL
Mutations in CD42d gives rise to Bernard-Soulier syndrome (BSS), which is a bleeding disorder and with the presence of giant platelets, is characterized by the absence or very reduced expression of members of the GPIb/IX/V CD42a-d complex. So far mutations have been found in the genes encoding CD42a, CD42b and CD42c in patients with BSS. CD42d mouse monoclonal antibodies are used for detection of auto- and allo-platelet antibodies with the MAIPA assay.
|MOLECULAR INTERACTIONS -|
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD42d
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD42d
Coexpression studies suggest that CD42d may be essential for the formation of the high affinity thrombin receptor.
Database accession numbers
Revised June 25, 2008