trophic

Neurotrophic factor that enhances survival and morphological differentiation of dopaminergic neurons and increases their high-affinity dopamine uptake. GDNF Protein, Human, Recombinant (His & SUMO) is expressed in E. coli expression system with N-6xHis-SUMO tag. The predicted molecular weight is 31.1 kDa and the accession number is P39905.

VPS1 domain-containing receptor SorCS1, also known as SORCS1 and SORCS, is a single-pass type I membrane protein that belongs to the SORCS family and SORCS1 subfamily. SORCS1 contains five BNR repeats and one PKD domain. SorCS1 is a member of the Vps1p-domain receptor family comprised of Sortilin, SorCS1, SorCS2, SorCS3, and SorLA. The common characteristic of these receptors is an N-terminal Vps1p domain, which either represents the only module of the luminal/extracellular moiety or is combined with additional domains. Family members play roles in protein transport and signal transduction. The individual receptors bind and internalize a variety of ligands, such as neuropeptides and trophic factors, and Sortilin and SorLA mediate trans-Golgi network-to-endosome sorting. Their prominent neuronal expression, several of the identified ligands, and results support the notion that members of this receptor family have important functions in neurogenesis, plasticity-related processes, and functional maintenance of the nervous system. Sortilin and SorLA mediate intracellular protein trafficking and sorting. SorCS1 binds platelet-derived growth factor-BB (PDGF-BB) and is expressed in isoforms differing only in their cytoplasmic domains. SorCS1 binds platelet-derived growth factor, a growth factor crucial for pericyte recruitment to the microvasculature, and may thus have a role in expanding or maintaining the islet vasculature.

Tumor necrosis factor receptor superfamily member 21(DR6) is a single-pass type I membrane protein and contains 1 death domain and 4 TNFR-Cys repeats. The protein may activate NF-kappa-B and promote apoptosis and it may activate JNK and be involved in T-cell differentiation.It is required for both normal cell body death and axonal pruning. Trophic-factor deprivation triggers the cleavage of surface APP by beta-secretase to release sAPP-beta which is further cleaved to release an N-terminal fragment of APP (N-APP). N-APP binds TNFRSF21 triggering caspase activation and degeneration of both neuronal cell bodies (via caspase-3) and axons (via caspase-6).