Electrophysiological basis of sour taste transduction

酸味转导的电生理基础

基本信息

批准号：
10627899
负责人：
Sue C. Kinnamon
金额：
$ 47.96万
依托单位：
UNIVERSITY OF SOUTHERN CALIFORNIA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-04-01 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10627899
关键词：
Acids Action Potentials Animals Applications Grants Behavior Behavior assessment Behavioral Brain region Brown Fat Calcium Cell Separation Cells Circumvallate Papilla Citrus Fruit Cytosol Data Defect Detection Development Diabetes Mellitus Diet Disease Electrophysiology (science)Epithelium Exhibits Family Fire - disasters Food Funding Fungiform Papilla Gene Expression Profile Gene Family Genes Goals Homologous Gene Human Hypertension In Situ Hybridization Integral Membrane Protein Investigation Ion Channel Ions Knock-out Knockout Mice Laboratories Maintenance Mammals Measures Mediating Membrane Modeling Molecular Mouse Strains Mus Mutate Nature Nerve Obesity Operant Conditioning Palate Physiological Physiological Processes Play Potassium Channel Property Protein Isoforms Protons Receptor Cell Reporter Role Salts Sensory Signal Transduction Sodium Chloride Stimulus Sweetening Agents System Taste Buds Taste Perception Testing Tongue Type III Epithelial Receptor Cell Xenopus oocyte cell type combat defined contribution dietary experimental study genetic testing immunocytochemistry improved in vivo lipid metabolism member novel patch clamp promoter receptor receptor function response screening sensor taste stimuli taste system taste transduction

项目摘要

Project Summary The broad goal of the proposed experiments is to identify key molecules that allow mammals to detect basic tastes and generate electrical responses that are conducted to brain regions. Molecular mechanisms of taste reception have been a subject of intense investigation over the last 30 years, with great strides made in identifying receptors for bitter, sweet and umami. Much less is known about the nature and function of receptors for sour, the taste that allows us to detect acids in spoiled foods or citrus fruits. In this proposal, we will begin to unravel this problem as we test the contribution of the newly discovered otopetrin proton channels in the transduction of acidic and ionic tastes. These experiments build on the progress made in the last grant application, where we used a combination of cellular, molecular and functional approaches to identify the pH sensitive ion channels in Type III taste receptor cells (TRCs) that mediate sour taste. Notably, we described a novel proton-selective ionic current that is likely to be a key component of sour taste transduction. In the last funding period, we successfully identified the gene that encodes the proton channel, through functional screening of genes enriched in Type III TRCs. Among 41 genes tested, we identified one, encoding the transmembrane protein Otop1 that upon expression induced a proton current in both Xenopus oocytes and HEK-293 cells. Interestingly, Otop1 was first identified as a gene mutated in mice with vestibular defects (“tilted” or tlt) but its function in the vestibular system and elsewhere in the body was not understood. Building on these new results, we propose three specific aims to test the role of the Otop channels in taste signaling. The first aim will examine the functional distribution of Otop1 across the tongue and palate epithelium, allowing us to answer the question of whether Otop1 is the sole ion channel mediating proton influx in the gustatory system. In the second aim, we will measure cellular responses to acids in wildtype and Otop1 KO mice in order to determine the degree to which Otop1 contributes to sensory responses, ex vivo. In the third aim, we will measure responses from gustatory nerves and assess behavioral thresholds for acid detection in wildtype and Otop1 KO mice to determine the extent to which Otop1 mediates responses to sour taste stimuli in vivo. Together our experiments will allow us to determine if Otop1 functions as a sour taste receptor. Our efforts to identify mechanisms of taste transduction may allow the development of taste modifiers that can be used to enhance palatability of food, reducing the need to add sweeteners that contribute to the development of diabetes or salts that contribute to hypertension. Moreover, the proposed experiments will provide basic information regarding the functional properties of this new family of proton channels that will help us understand their contributions to diverse physiological processes, including brown fat metabolism and the development and maintenance of the vestibular system.

项目摘要提出的实验的广泛目标是识别允许哺乳动物检测基本的关键分子口味并产生对大脑区域进行的电气反应。味道的分子机制在过去的30年中，接待一直是一项激烈调查的主题识别苦，甜和鲜味的受体。对受体的性质和功能知之甚少对于酸味，使我们能够在变质的食物或柑橘类水果中检测到酸的味道。在此提案中，我们将开始当我们测试新发现的otopetrin质子通道的贡献时，请解散这个问题酸性和离子口味的转导。这些实验建立在上次赠款中取得的进展基础上应用，我们使用细胞，分子和功能方法的组合来识别pH 介导酸味的III型味道受体细胞（TRC）中的敏感离子通道。值得注意的是，我们描述了一个新型质子选择性离子电流可能是酸味转移的关键组成部分。在最后资金期，我们通过功能筛选成功地确定了编码质子通道的基因富含III型TRC的基因。在测试的41个基因中，我们鉴定了一个编码跨膜的基因蛋白OTOP1在表达后诱导异爪蟾卵母细胞和HEK-293细胞中质子电流。有趣的是，otop1首先被鉴定为具有前庭缺陷的小鼠突变的基因（“倾斜”或TLT），但它的基因不了解前庭系统和人体其他地方的功能。以这些新结果为基础我们提出了三个特定的目标，以测试OTOP通道在味觉信号传导中的作用。第一个目标将检查 OTOP1在舌头和上皮上皮的功能分布，使我们能够回答这个问题 otop1是否是造成质子在味道系统中介导质子影响的唯一离子通道。在第二个目标中，我们将测量野生型和OTOP1 KO小鼠中对酸的细胞反应，以确定程度 OTOP1有助于感觉响应，离体。在第三个目标中，我们将衡量来自在野生型和OTOP1 KO小鼠中检测酸检测的味觉神经和评估行为阈值确定OTOP1在体内介导对酸味刺激的反应的程度。一起实验将使我们能够确定OTOP1是否作为酸味接收器的功能。我们为确定口味机制的努力转导可能允许开发口味修饰符，以增强食物的可口性，减少添加甜味剂的需求，以有助于糖尿病或盐的发展高血压。此外，拟议的实验将提供有关功能的基本信息这个新的质子渠道家族的财产将帮助我们了解他们对潜水员的贡献生理过程，包括棕色脂肪代谢以及前庭的发展和维护系统。

项目成果

期刊论文数量（12）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Activation Stoichiometry and Pore Architecture of TRPA1 Probed with Channel Concatemers.

DOI：
10.1038/s41598-018-35435-y
发表时间：
2018-11-20
期刊：
Scientific reports
影响因子：
4.6
作者：
Ye W;Tu YH;Cooper AJ;Zhang Z;Katritch V;Liman ER
通讯作者：
Liman ER

The evolution of sour taste.

DOI：
10.1098/rspb.2021.1918
发表时间：
2022-02-09
期刊：
Proceedings. Biological sciences
影响因子：
0
作者：
Frank HER;Amato K;Trautwein M;Maia P;Liman ER;Nichols LM;Schwenk K;Breslin PAS;Dunn RR
通讯作者：
Dunn RR

The proton channel OTOP1 is a sensor for the taste of ammonium chloride.

DOI：
10.1038/s41467-023-41637-4
发表时间：
2023-10-05
期刊：
NATURE COMMUNICATIONS
影响因子：
16.6
作者：
Liang, Ziyu;Wilson, Courtney E.;Teng, Bochuan;Kinnamon, Sue C.;Liman, Emily R.
通讯作者：
Liman, Emily R.

Structural motifs for subtype-specific pH-sensitive gating of vertebrate otopetrin proton channels.

DOI：
10.7554/elife.77946
发表时间：
2022-08-03
期刊：
ELIFE
影响因子：
7.7
作者：
Teng, Bochuan;Kaplan, Joshua P.;Liang, Ziyu;Krieger, Zachary;Tu, Yu-Hsiang;Burendei, Batuujin;Ward, Andrew B.;Liman, Emily R.
通讯作者：
Liman, Emily R.

TRP Channels: Pain enters through the side door.

TRP通道：疼痛从侧门进入。