G protein coupled receptors and chemosensation

• Grant number: 07/50743-9
• Support Opportunities: Research Projects - Thematic Grants
• Start date: July 01, 2007
• End date: December 31, 2011
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Bettina Malnic
• Grantee: Bettina Malnic
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 11/22611-6 - Identification of non-coding RNAs expressed in the olfactory epithelium, BP.DD

Abstract

Animais detect chemical cues that are present in the environment through a large family of receptors which belong to the G protein coupled receptors superfamily (GPCRs). These receptors are expressed in specialized cell types that are involved in different functions. Odorant receptors are expressed in the olfactory sensory neurons of the nose, taste receptors are expressed in the taste cells of the tongue, and pheromone receptors are expressed in the sensory neurons of the vomeronasal organ. Ligand induced activation of these receptors ultimately results in sensory perception. The aim of the present project is to analyze the following aspects relative to two different GPCR mediated sensorial modalities, smell and taste: 1) we will study the mechanisms of odorant signal transduction regulation in vivo. The role of Ric-8B, a putative GEF (guanine nucleotide exchange factor) which has been previously identified in our laboratory and shown to regulate the olfactory G protein Golf, will be analyzed; 2) mice have around 1000 OR genes, however, only one OR gene allele is expressed per olfactory sensory neuron. We will investigate the mechanisms that regulate OR gene expression in olfactory sensory neurons; 3) sweet tastants are detected bya heterodimer of GPCRs, constituted by the T1R2 and T1R3 receptors. We aim to isolate molecules that modulate human sweet receptor function. (AU)