Dataset Information

Taste dysfunction in BTBR mice due to a mutation of Itpr3, the inositol triphosphate receptor 3 gene.

ABSTRACT: The BTBR T+ tf/J (BTBR) mouse strain is indifferent to exemplars of sweet, Polycose, umami, bitter, and calcium tastes, which share in common transduction by G protein-coupled receptors (GPCRs). To investigate the genetic basis for this taste dysfunction, we screened 610 BTBR×NZW/LacJ F2 hybrids, identified a potent QTL on chromosome 17, and isolated this in a congenic strain. Mice carrying the BTBR/BTBR haplotype in the 0.8-Mb (21-gene) congenic region were indifferent to sweet, Polycose, umami, bitter, and calcium tastes. To assess the contribution of a likely causative culprit, Itpr3, the inositol triphosphate receptor 3 gene, we produced and tested Itpr3 knockout mice. These were also indifferent to GPCR-mediated taste compounds. Sequencing the BTBR form of Itpr3 revealed a unique 12 bp deletion in Exon 23 (Chr 17: 27238069; Build 37). We conclude that a spontaneous mutation of Itpr3 in a progenitor of the BTBR strain produced a heretofore unrecognized dysfunction of GPCR-mediated taste transduction.

SUBMITTER: Tordoff MG

PROVIDER: S-EPMC3783815 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Taste dysfunction in BTBR mice due to a mutation of Itpr3, the inositol triphosphate receptor 3 gene.

Tordoff Michael G MG Ellis Hillary T HT

Physiological genomics 20130716 18

The BTBR T+ tf/J (BTBR) mouse strain is indifferent to exemplars of sweet, Polycose, umami, bitter, and calcium tastes, which share in common transduction by G protein-coupled receptors (GPCRs). To investigate the genetic basis for this taste dysfunction, we screened 610 BTBR×NZW/LacJ F2 hybrids, identified a potent QTL on chromosome 17, and isolated this in a congenic strain. Mice carrying the BTBR/BTBR haplotype in the 0.8-Mb (21-gene) congenic region were indifferent to sweet, Polycose, umami ...[more]

PMID: 23859941

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Dataset Information

Taste dysfunction in BTBR mice due to a mutation of Itpr3, the inositol triphosphate receptor 3 gene.

Publications

Taste dysfunction in BTBR mice due to a mutation of Itpr3, the inositol triphosphate receptor 3 gene.

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