PTN
Description
The PTN (pleiotrophin) is a protein-coding gene located on chromosome 7.
PTN may refer to:
PTN (Pleiotrophin) is a secreted growth factor that signals through cell-surface proteoglycan and non-proteoglycan receptors. It binds to proteoglycan receptors through their chondroitin sulfate (CS) groups, regulating various cellular processes including proliferation, survival, growth, differentiation, and migration in tissues like neurons and bones. PTN also plays a role in synaptic plasticity and learning by inhibiting long-term synaptic potentiation. PTN binds to PTPRZ1, neutralizing the negative charges of its CS chains, leading to PTPRZ1 clustering, dimerization, and inactivation of its phosphatase activity. This inactivation results in increased tyrosine phosphorylation of PTPRZ1 substrates like ALK, CTNNB1, or AFAP1L2, activating the PI3K-AKT pathway. PTN's binding to PTPRZ1 also controls oligodendrocyte precursor cell differentiation by enhancing AFAP1L2 phosphorylation. PTN forms a complex with PTPRZ1 and integrin alpha-V/beta-3, stimulating endothelial cell migration through SRC dephosphorylation and activation, leading to ITGB3 'Tyr-773' phosphorylation. In the adult hippocampus, PTN promotes dendritic arborization, spine development, and functional integration of newborn granule neurons through ALK by activating AKT signaling. PTN binds to GPC2 and CSPGs at the neuron surface, abrogating PTPRS binding to CSPGs and promoting neurite outgrowth. PTN also binds to SDC3, mediating bone formation by recruiting osteoblasts/osteoblast precursors to bone deposition sites. PTN binds to ALK, promoting cell survival and proliferation through MAPK pathway activation. It inhibits neural stem cell proliferation and enhances differentiation by inhibiting FGF2-induced fibroblast growth factor receptor signaling. PTN mediates regulatory mechanisms in hemostasis, hematopoietic regeneration, and maintaining myeloid/lymphoid regeneration balance. It may also play roles in the female reproductive system, auditory response, and the progesterone-induced decidualization pathway. PTN interacts with ALK and NEK6. It interacts with PTPRZ1 through chondroitin sulfate groups, promoting homooligomer formation and impairing tyrosine phosphatase activity. PTN forms a complex with PTPRZ1 and CTNNB1, inactivating PTPRZ1 phosphatase activity and stimulating CTNNB1 tyrosine phosphorylation. It interacts with ITGB3 and ITGA5. PTN forms a complex with PTPRZ1 and integrin alpha-V/beta-3, stimulating endothelial cell migration through ITGB3 'Tyr-773' phosphorylation. PTN interacts with SDC3 through heparan sulfate chains, mediating neurite outgrowth promotion and osteoblast recruitment. It interacts with GPC2 through heparan sulfate, promoting neurite outgrowth by binding to CSPGs, releasing PTPRS from CSPGs, and enabling binding to GPC2 heparan sulfate.
PTN is also known as HARP, HB-GAM, HBBM, HBGF-8, HBGF8, HBNF, HBNF-1, NEGF1, OSF-1.
