Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissue...Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in vivo.Methods:To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues,multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique.A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the zygotes.Then,T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder mice.Quantitative real-time polymerase chain reaction(qRT-PCR)and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste buds.Perception to taste substance was also studied using twobottle preference tests.Results:We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 technique.Immunostaining results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant mice.But qRT-PCR results revealed the changed expression profile of m Tas2rs gene in taste buds of these mutant mice.With two-bottle preference tests,these mutant mice eliminate responses to cycloheximide due to genetic mutation of Tas2r105.In addition,these mutant mice showed a loss of taste perception to quinine dihydrochloride,denatonium benzoate,and cucurbitacin B(CuB).Gnat3-mediated taste receptor and its signal pathway contribute to CuB perception.Conclusions:These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues.展开更多
This study examines a common phenomenon that is greatly ignored by the clinical community for numerous reasons. Many people for a multitude of reasons experience taste alterations. The supertaster phenomenon is an alt...This study examines a common phenomenon that is greatly ignored by the clinical community for numerous reasons. Many people for a multitude of reasons experience taste alterations. The supertaster phenomenon is an alteration of taste that requires more investigation. In this study, a proband was examined for subjective reports of a taste alteration to determine its nature through a medical history examination and interview as well as any recollections of the taste disorder in her life. Through this examination, it was found that medical history examination and interview of the proband that many members of her nuclear family showed traits of the same taste disorder or in the case of one family member being a suspect for the taste alteration and one member not showing any signs because of genetic diversity as a half-sibling. Taste disorders are heritable, have multiple health and mental health consequences, influence life choices including mate choice, avoidance behaviors, social choices, alcohol use/abuse, smoking, food choices, and more. More awareness is needed in the research and clinical community into taste alterations as well as calls for future research from neuroscience, biomedical science, life science, and allied science community to investigate taste alterations.展开更多
基金Shanghai Science and Technology Commission“R&D Public Service Platform and Institutional Capacity Improvement Project”,Grant/Award Number:21DZ2291300National Science and Technology Major Project,Grant/Award Number:2017ZX10304402-001-006 and 2017ZX10304402-001-012Start-on Funding from Shanghai Public Health Clinical Center,Grant/Award Number:KY-GW-2019-11,KYGW-2019-19 and KY-GW-2021-39。
文摘Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in vivo.Methods:To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues,multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique.A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the zygotes.Then,T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder mice.Quantitative real-time polymerase chain reaction(qRT-PCR)and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste buds.Perception to taste substance was also studied using twobottle preference tests.Results:We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 technique.Immunostaining results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant mice.But qRT-PCR results revealed the changed expression profile of m Tas2rs gene in taste buds of these mutant mice.With two-bottle preference tests,these mutant mice eliminate responses to cycloheximide due to genetic mutation of Tas2r105.In addition,these mutant mice showed a loss of taste perception to quinine dihydrochloride,denatonium benzoate,and cucurbitacin B(CuB).Gnat3-mediated taste receptor and its signal pathway contribute to CuB perception.Conclusions:These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues.
文摘This study examines a common phenomenon that is greatly ignored by the clinical community for numerous reasons. Many people for a multitude of reasons experience taste alterations. The supertaster phenomenon is an alteration of taste that requires more investigation. In this study, a proband was examined for subjective reports of a taste alteration to determine its nature through a medical history examination and interview as well as any recollections of the taste disorder in her life. Through this examination, it was found that medical history examination and interview of the proband that many members of her nuclear family showed traits of the same taste disorder or in the case of one family member being a suspect for the taste alteration and one member not showing any signs because of genetic diversity as a half-sibling. Taste disorders are heritable, have multiple health and mental health consequences, influence life choices including mate choice, avoidance behaviors, social choices, alcohol use/abuse, smoking, food choices, and more. More awareness is needed in the research and clinical community into taste alterations as well as calls for future research from neuroscience, biomedical science, life science, and allied science community to investigate taste alterations.
