ricin B-type lectin domain, beta-trefoil fold, found in receptor-type tyrosine-protein phosphatase beta (PTPRB) isoform e and similar proteins
PTPRB (EC 3.1.3.48), also called protein-tyrosine phosphatase beta, R-PTP-beta, vascular endothelial protein tyrosine phosphatase, or VE-PTP, plays an important role in blood vessel remodeling and angiogenesis. It is not necessary for the initial formation of blood vessels but is essential for their maintenance and remodeling. It is also essential for the maintenance of endothelial cell contact integrity and for the adhesive function of VE-cadherin in endothelial cells, which requires the presence of plakoglobin. The subfamily corresponds to PTPRB isoform e, which contains an extra ricin B-type lectin domain at the N-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain may harbor a sugar-binding pocket.
Jiyao W et al.(2023). "The conserved domain database in 2023.",