Targeted Taste Cell-specific Overexpression of Brain-derived Neurotrophic Factor in Adult Taste Buds Elevates Phosphorylated TrkB Protein Levels in Taste Cells, Increases Taste Bud Size, and Promotes Gustatory Innervation

Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel t...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 2012-05, Vol.287 (20), p.16791-16800
Main Authors: Nosrat, Irina V., Margolskee, Robert F., Nosrat, Christopher A.
Format: Article
Language:English
Subjects:
Animals
Brain-derived Neurotrophic Factor (BDNF)
Brain-Derived Neurotrophic Factor - biosynthesis
Brain-Derived Neurotrophic Factor - genetics
Development
Gene Expression
Gene Expression Regulation, Enzymologic - genetics
Growth Factors
Gustation
Membrane Glycoproteins - biosynthesis
Membrane Glycoproteins - genetics
Mice
Mice, Transgenic
NCAM
Neural Cell Adhesion Molecules - biosynthesis
Neural Cell Adhesion Molecules - genetics
Neurobiology
Neurotrophins
Organ Size - genetics
Protein-Tyrosine Kinases - biosynthesis
Protein-Tyrosine Kinases - genetics
Receptors, Purinergic P2X3 - biosynthesis
Receptors, Purinergic P2X3 - genetics
Taste Buds
Taste Buds - metabolism
Taste Perception
Tongue - innervation
Tongue - metabolism
Transgenic Mice
TrkB
Up-Regulation - genetics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Brain-derived neurotrophic factor (BDNF) is the most potent neurotrophic factor in the peripheral taste system during embryonic development. It is also expressed in adult taste buds. There is a lack of understanding of the role of BDNF in the adult taste system. To address this, we generated novel transgenic mice in which transgene expression was driven by an α-gustducin promoter coupling BDNF expression to the postnatal expression of gustducin in taste cells. Immunohistochemistry revealed significantly stronger BDNF labeling in taste cells of high BDNF-expressing mouse lines compared with controls. We show that taste buds in these mice are significantly larger and have a larger number of taste cells compared with controls. To examine whether innervation was affected in Gust-BDNF mice, we used antibodies to neural cell adhesion molecule (NCAM) and ATP receptor P2X3. The total density of general innervation and specifically the gustatory innervation was markedly increased in high BDNF-expressing mice compared with controls. TrkB and NCAM gene expression in laser capture microdissected taste epithelia were significantly up-regulated in these mice. Up-regulation of TrkB transcripts in taste buds and elevated taste cell-specific TrkB phosphorylation in response to increased BDNF levels indicate that BDNF controls the expression and activation of its high affinity receptor in taste cells. This demonstrates a direct taste cell function for BDNF. BDNF also orchestrates and maintains taste bud innervation. We propose that the Gust-BDNF transgenic mouse models can be employed to further dissect the specific roles of BDNF in the adult taste system. There is a lack of information about the roles of neurotrophin BDNF in adult taste buds. We generated taste cell-specific BDNF-overexpressing mice. Increased BDNF elevates TrkB activation, increases transcription of NCAM-TrkB, leads to larger taste buds, and increases taste cell number and taste-specific innervation. BDNF has local and neuronal influences. BDNF might be involved in the supertasting phenomenon.
ISSN:0021-9258
1083-351X
DOI:10.1074/jbc.M111.328476