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General Comment |
The GDNF family of neurotrophic factors currently has four members: neurturin (NRTN), glial cell
line-derived neurotrophic factor (GDNF), persephin, and artemin. These proteins are potent survival
factors for several populations of central and peripheral neurons. The receptors for these factors are
complexes that include the Ret tyrosine kinase receptor and a GPI-linked, ligand-binding component
called GDNF family receptor alpha 1-4 (GFRalpha1-4). ()The glial cell line-derived neurotrophic factor (GDNF) ligands (GDNF, Neurturin , and Persephin
) signal through a multicomponent receptor system composed of a high-affinity binding component
(GFRalpha1-GFRalpha4) and a common signaling component (RET). Here, we report the identification
of Artemin, a novel member of the GDNF family, and demonstrate that it is the ligand for the former
orphan receptor GFRalpha3-RET. Artemin is a survival factor for sensory and sympathetic neurons in
culture, and its expression pattern suggests that it also influences these neurons in vivo. Artemin can also
activate the GFRalpha1-RET complex and supports the survival of dopaminergic midbrain neurons in
culture, indicating that like GDNF (GFRalpha1-RET) and NTN (GFRalpha2-RET), Artemin has a
preferred receptor (GFRalpha3-RET) but that alternative receptor interactions also occur.
NCBI Summary:
The protein encoded by this gene is a member of the glial cell line-derived neurotophic factor (GDNF) family of ligands which are a group of ligands within the TGF-beta superfamily of signaling molecules. GDNFs are unique in having neurotrophic properties and have potential use for gene therapy in neurodegenrative disease. Artemin has been shown in culture to support the survival of a number of periferal neuron populations and at least one population of dopaminergic CNS neurons. Its role in the PNS and CNS is further substantiated by its expression pattern in the proximity of these neurons. This protein is a ligand for the RET receptor and uses GFR-alpha 3 as a coreceptor. Four alternatively spliced transcripts have been described, two of which encode the same protein.
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Comment |
Artemin-like immunoreactivity in the zebrafish, Danio rerio.
Lucini C, et al .
Artemin is a member of the glial cell line-derived neurotrophic factor (GDNF) family. It is a neurotrophic factor that supports neurite migration and outgrowth and survival of the sympathetic and sensory nervous system. Artemin has been studied in human and murine tissues, but no study has been devoted to nonmammalian species. Zebrafish is a teleost fish belonging to the family Ciprinidae, which is becoming an important model species for genetic and developmental studies. Thus, the aim of the present investigation was to evaluate, by immunochemical and immunocytochemical analyses, the tissue distribution pattern of artemin in zebrafish. Different isoforms of artemin with corresponding different molecular weights were detected in the brain, muscle, testis, ovary, kidney, gut, and gills of zebrafish by Western blot analysis. Immunocytochemical analysis showed artemin-like immunoreactivity in different cell types: in glial cells and rare neurons of the central nervous system, taste buds, retina, neuromasts of the lateral line, dorsal root ganglia, sympathetic ganglia, gill epithelium, tubular kidney epithelium, gut epithelium and ganglia, pancreas, thyroid, hypothalamus, testis, and ovary. These results indicate a wide distribution of artemin-like immunoreactivity in adult zebrafish, related to the presence of different forms of artemin. These findings might suggest a complex maturation pattern of artemin, whose forms could also exert different roles in zebrafish tissues.
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