title: Depletion of bitter taste transduction leads to massive spermatid loss in transgenic mice.
abstract: Bitter taste perception is an important sensory input warning against the ingestion of toxic and noxious substances. Bitter receptors, a family of ~30 highly divergent G-protein-coupled receptors, are exclusively expressed in taste receptor cells that contain the G-protein α-subunit gustducin, bind to α-gustducin in vitro, and respond to bitter tastes in functional expression assays. We generated a taste receptor type 2 member 5 (T2R5)-Cre/green fluorescent protein reporter transgenic mouse to investigate the tissue distribution of T2R5. Our results showed that Cre gene expression in these mice was faithful to the expression of T2R5 in taste tissue. More surprisingly, immunostaining and X-gal staining revealed T2R5 expression in the testis. Ablation of T2R5 + cells led to a smaller testis and removed the spermatid phase from most of the seminiferous tubules. The entire taste transduction cascade (α-gustducin, Ggamma13, phospholipase Cβ2) was detected in spermatogenesis, whereas transient receptor potential, cation channel subfamily M member 5 (Trpm5), was observed only in the later spermatid phase. In short, our results indicate that the taste transduction cascade may be involved in spermatogenesis.
authors.affiliation: Laboratory of Developmental Biology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, People's Republic of China. lifengwest@gmail.com
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Minliang
authors.initials: M
authors.lastname: Zhou
mesh_terms: D000370:Ageusia / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D003433:Crosses, Genetic; D017930:Genes, Reporter; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009845:Oligospermia / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D009929:Organ Size; D009928:Organ Specificity; D054799:Phospholipase C beta / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D013087:Spermatids / Q000378:metabolism; D013091:Spermatogenesis; D050053:TRPM Cation Channels / Q000378:metabolism; D013650:Taste Buds / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D013737:Testis / Q000166:cytology / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D000098706:Taste Receptors, Type 2
chemical_list: C510865:Ggamma13 protein, mouse; D020033:Protein Isoforms; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins; D050053:TRPM Cation Channels; C498617:Trpm5 protein, mouse; D000098706:Taste Receptors, Type 2; D054799:Phospholipase C beta; C518037:Plcb2 protein, mouse; C524407:GNAT3 protein, mouse; D020962:Heterotrimeric GTP-Binding Proteins