Distribution of glial cell line-derived neurotrophic factor receptor alpha-1 in the brain of adult zebrafish.
Glial cell line-derived neurotrophic factor (GDNF) is a potent trophic factor for several types of neurons in the central and peripheral nervous systems. The biological activity of GDNF is mediated by a multicomponent receptor complex that includes a common transmembrane signaling component (the rearranged during transfection (RET) proto-oncogene product, a tyrosine kinase receptor) as well as a GDNF family receptor alpha (GFRalpha) subunit, a high-affinity glycosyl phosphatidylinositol (GPI)-linked binding element. Among the four known GFRalpha subunits, GFRalpha1 preferentially binds to GDNF. In zebrafish (Danio rerio) embryos, the expression of the GFRalpha1a and GFRalpha1b genes has been shown in primary motor neurons, the kidney, and the enteric nervous system. To examine the activity of GFRalpha in the adult brain of a lower vertebrate, we have investigated the localization of GFRalpha1a and GFRalpha1b mRNA and the GFRalpha1 protein in zebrafish. GFRalpha1a and GFRalpha1b transcripts were observed in brain extracts by reverse transcription-polymerase chain reaction. Whole-mount in-situ hybridization experiments revealed a wide distribution of GFRalpha1a and GFRalpha1b mRNAs in various regions of the adult zebrafish brain. These included the olfactory bulbs, dorsal and ventral telencephalic area (telencephalon), preoptic area, dorsal and ventral thalamus, posterior tuberculum and hypothalamus (diencephalon), optic tectum (mesencephalon), cerebellum, and medulla oblongata (rhombencephalon). Finally, expression patterns of the GFRalpha1 protein, detected immunohistochemically, correlated well with the mRNA expression and provided further insights into translational activity at the neuroanatomical level. In conclusion, the current study demonstrated that the presence of GFRalpha1 persists beyond the embryonic development of the zebrafish brain and, together with the GDNF ligand, is probably implicated in the brain physiology of an adult teleost fish.
Lucini
Carla
C
Department of Biological Structures, Functions and Technology, University of Naples 'Federico II', Naples, Italy. carla.lucini@unina.it
Carla
Lucini
L
Facello
Bruna
B
Bruna
Facello
F
Maruccio
Lucianna
L
Lucianna
Maruccio
M
Langellotto
Fernanda
F
Fernanda
Langellotto
L
Sordino
Paolo
P
Paolo
Sordino
S
Castaldo
Luciana
L
Luciana
Castaldo
C
D000818:Animals; D001921:Brain / Q000378:metabolism*; D004027:Diencephalon / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors / Q000235:genetics / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008297:Male; D008636:Mesencephalon / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013687:Telencephalon / Q000378:metabolism; D015027:Zebrafish / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D012333:RNA, Messenger; D029961:Zebrafish Proteins; C494996:gfra1a protein, zebrafish