Regulation of kainate receptor expression in cone bipolar cells

视锥双极细胞中红藻氨酸受体表达的调节

基本信息

批准号：
10367733
负责人：
Anis Contractor
金额：
$ 43.44万
依托单位：
NORTHWESTERN UNIVERSITY AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-30 至 2026-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10367733
关键词：
AMPA Receptors Acids Acute Address Adult Affinity Anatomy Area Autoimmune Diseases Binding Brain CRISPR/Cas technology Cell Culture Techniques Cells Chief Cell Communication Cone Contractor Data Databases Development Epilepsy Excision Excitatory Synapse Frequencies Genetic Diseases Glutamate Receptor Glutamates Health Human Individual Interneurons Kainic Acid Receptors Kinetics Knock-out Light Measures Mediating Metabotropic Glutamate Receptors Microscopy Modality Modification Molecular Molecular Genetics Mood Disorders Mus Pathway interactions Perfusion Pharmaceutical Preparations Photoreceptors Physiologic pulse Physiological Play Primates Process Property Proteins Proteomics RNA Splicing Receptor Cell Recovery Regulation Resolution Retina Retinal Cone Role Signal Transduction Spermophilus Structure Synapses System Vision Work authority base cell type desensitization experimental study genetic manipulation in vivo kainate mouse model outer plexiform layer pain signal preservation receptor receptor expression receptor function response tool transcriptomics virus genetics visual information

项目摘要

The long term objective of this work is to understand the molecular genetic basis for how the retina transmits and processes the signals produced when lights are turned off. Cone photoreceptors mediate vision during daylight and use glutamate as their transmitter. The cone signals are carried across the retina by two functional classes of bipolar cells, On and Off, which have different glutamate receptors that cause them to depolarize (ie, signal) either at light-on or -off, respectively. Each functional class of bipolar cell can be subdivided into 5-6 anatomical types. This study focuses on the Off bipolar cells that chiefly express sign-preserving kainate-type glutamate receptors (subunits GluK1-5). Surprisingly, while AMPA receptors predominate at most CNS synapses, kainate receptors predominate at the cone synapses of most of the Off bipolar cell types. They are important to study for at least four reasons. First, the temporal signaling properties of kainate receptors differ from those of AMPA receptors, and these differences are likely to change the size and timing of the Off signals traversing the retina in as yet poorly understood ways. Second, the kainate receptors at most well-studied synapses almost always contain the GluK2 subunit, whereas the Off bipolar cells choose the less well-studied GluK1 subunit as their main subunit instead. Third, Off bipolar cells express Neto1, an auxiliary receptor subunit that profoundly alters the in vivo responses of GluK2-containing receptors. The effect of Neto1 on endogenous GluK1-containing receptors has not yet been studied. And fourth, while the functional properties of different kainate receptors on the Off bipolar cell have been described, the molecular basis for their diverse responses has not been established. To determine the subunit basis for signaling at the Off bipolar cell synapse, we propose to study synaptic responses in mice in which receptor subunits (GluK1-GluK5) are individually knocked out either permanently or acutely. Similar studies will be performed to define the role of the auxiliary subunit Neto1 in communication. Three specific aims will 1) determine the subunits that mediate synaptic responses in Off bipolar cell types 1a, 2, and 3a; 2) determine the function of Neto proteins in signaling at the Off bipolar cell synapse; and, 3) determine the physiological function of the GluK1-1d subunit, which is unique to the retina, the molecular factors that localize the GluK1-1d subunit to the synapse.

这项工作的长期目标是了解视网膜如何发生变化的分子遗传学基础传输和处理灯关闭时产生的信号。视锥细胞感光器在白天调节视力并使用谷氨酸作为其传递器。携带锥体信号两种功能类别的双极细胞（开和关）穿过视网膜，它们具有不同的功能谷氨酸受体，导致它们分别在开灯或关灯时去极化（即发出信号）。双极细胞的每个功能类别可细分为 5-6 个解剖类型。这项研究重点关注主要表达保留信号的红藻氨酸型谷氨酸的非双极细胞受体（GluK1-5 亚基）。令人惊讶的是，虽然 AMPA 受体在大多数中枢神经系统中占主导地位突触，红藻氨酸受体在大多数非双极细胞的锥体突触中占主导地位类型。它们之所以重要，至少有四个原因。一、时间信号特性红藻氨酸受体的功能与 AMPA 受体的功能不同，这些差异很可能改变穿过视网膜的关闭信号的大小和时间，目前尚知之甚少方式。其次，大多数经过充分研究的突触中的红藻氨酸受体几乎总是包含 GluK2 亚基，而 Off 双极细胞则选择研究较少的 GluK1 亚基作为其主要亚基代替。第三，Off双极细胞表达Neto1，这是一种辅助受体亚基，深刻改变含 GluK2 受体的体内反应。 Neto1对的影响内源性含 GluK1 受体尚未被研究。第四，虽然功能性已经描述了非双极细胞上不同红藻氨酸受体的特性，分子他们的不同反应的基础尚未确定。确定亚基基础关闭双极细胞突触的信号传导，我们建议研究小鼠的突触反应，其中受体亚基（GluK1-GluK5）被单独永久或急性敲除。将进行类似的研究来定义辅助亚基 Neto1 在通信中的作用。三个具体目标将 1) 确定在非双相情感障碍中介导突触反应的亚基细胞类型 1a、2 和 3a； 2) 确定 Neto 蛋白在 Off 双极信号传导中的功能细胞突触； 3）确定GluK1-1d亚基的生理功能，这是独一无二的对于视网膜，将 GluK1-1d 亚基定位于突触的分子因子。