Expression of GDNF and GFR alpha 1 in mouse taste bud cells.
GDNF (glial cell line-derived neurotrophic factor) affects the survival and maintenance of central and peripheral neurons. Using an immunocytochemical method, we examined whether the taste bud cells in the circumvallate papillae of normal mice expressed GDNF and its GFR alpha 1 receptor. Using double immunostaining for either of them and NCAM, PGP 9.5, or alpha-gustducin, we additionally sought to determine what type of taste bud cells expressed GDNF or GFR alpha 1, because NCAM is reported to be expressed in type-III cells, PGP 9.5, in type-III and some type-II cells, and alpha-gustducin, in some type-II cells. Normal taste bud cells expressed both GDNF and GFR alpha 1. The percentage of GDNF-immunoreactive cells among all taste bud cells was 31.63%, and that of GFR alpha 1-immunoreactive cells, 83.21%. Confocal laser scanning microscopic observations after double immunostaining showed that almost none of the GDNF-immunoreactive cells in the taste buds were reactive with anti-NCAM or anti-PGP 9.5 antibody, but could be stained with anti-alpha-gustducin antibody. On the other hand, almost all anti-PGP 9.5- or anti-alpha-gustducin-immunoreactive cells were positive for GFR alpha 1. Thus, GDNF-immunoreactive cells did not include type-III cells, but type-II cells, which are alpha-gustducin-immunoreactive; on the other hand, GFR alpha 1-immunoreactive cells included type-II and -III cells, and perhaps type-I cells. We conclude that GDNF in the type-II cells may exert trophic actions on type-I, -II, and -III taste bud cells by binding to their GFR alpha 1 receptors.
Takeda
Masako
M
Department of Oral Anatomy, School of Dentistry, Health Sciences University of Hokkaido, Tobetsu, Ishikari, Hokkaido 061-0293, Japan. matakeda@hoku-iryo-u.ac.jp
Suzuki
Yuko
Y
Obara
Nobuko
N
Uchida
Nobuhiko
N
Kawakoshi
Kentaro
K
D000818:Animals; D002628:Chemoreceptor Cells / Q000166:cytology / Q000378:metabolism*; D051100:Glial Cell Line-Derived Neurotrophic Factor; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D007150:Immunohistochemistry; D051379:Mice; D008815:Mice, Inbred Strains; D009414:Nerve Growth Factors / Q000378:metabolism*; D019006:Neural Cell Adhesion Molecules / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D013649:Taste / Q000502:physiology*; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism*; D014018:Tissue Distribution; D014059:Tongue / Q000166:cytology / Q000378:metabolism; D015293:Transducin / Q000378:metabolism; D043222:Ubiquitin Thiolesterase / Q000378:metabolism
C495040:Gdnf protein, mouse; C494988:Gfra1 protein, mouse; D051100:Glial Cell Line-Derived Neurotrophic Factor; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; D009414:Nerve Growth Factors; D019006:Neural Cell Adhesion Molecules; D011518:Proto-Oncogene Proteins; C075192:gustducin; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases; C489034:UCHL1 protein, rat; D043222:Ubiquitin Thiolesterase; D015293:Transducin