Genetic dissection of TrkB activated signalling pathways required for specific aspects of the taste system

Neural Development

Liliana Minichiello¹  Chinnavuth Vatanashevanopakorn²  Jacqueline M Horn¹  Juraj Koudelka³ 

[1] Department of Pharmacology, University of Oxford, OX1 3QT Oxford, UK;Department of Biochemistry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand;Centre for Neuroregeneration, University of Edinburgh, EH16 4SB Edinburgh, UK

关键词: Taste receptors;    Taste buds;    Survival;    Gustatory system;    TrkB signalling;    Neurotrophin-4;    Brain derived neurotrophic factor;   

Others  :  1146404
DOI  :  10.1186/1749-8104-9-21

 received in 2014-07-03, accepted in 2014-09-18,  发布年份 2014

【 摘 要 】

Background

Neurotrophin-4 (NT-4) and brain derived neurotrophic factor (BDNF) bind to the same receptor, Ntrk2/TrkB, but play distinct roles in the development of the rodent gustatory system. However, the mechanisms underlying these processes are lacking.

Results

Here, we demonstrate, in vivo, that single or combined point mutations in major adaptor protein docking sites on TrkB receptor affect specific aspects of the mouse gustatory development, known to be dependent on BDNF or NT-4. In particular, mice with a mutation in the TrkB-SHC docking site had reduced gustatory neuron survival at both early and later stages of development, when survival is dependent on NT-4 and BDNF, respectively. In addition, lingual innervation and taste bud morphology, both BDNF-dependent functions, were altered in these mutants. In contrast, mutation of the TrkB-PLCγ docking site alone did not affect gustatory neuron survival. Moreover, innervation to the tongue was delayed in these mutants and taste receptor expression was altered.

Conclusions

We have genetically dissected pathways activated downstream of the TrkB receptor that are required for specific aspects of the taste system controlled by the two neurotrophins NT-4 and BDNF. In addition, our results indicate that TrkB also regulate the expression of specific taste receptors by distinct signalling pathways. These results advance our knowledge of the biology of the taste system, one of the fundamental sensory systems crucial for an organism to relate to the environment.

【 授权许可】

   
2014 Koudelka et al.; licensee BioMed Central Ltd.

【 图 表 】

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