Calcium coding mechanisms in plant cell growth and immunity

植物细胞生长和免疫中的钙编码机制

基本信息

批准号：
10430218
负责人：
Sheng Luan
金额：
$ 40.08万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10430218
关键词：
Address Affect Alzheimer&apos s Disease Angiosperms Animal Structures Animals Arabidopsis Back Binding Biochemical Biological Assay Biological Models Ca(2+)-Transporting ATPase Calcium Calcium Channel Calcium Oscillations Calcium Signaling Calcium Spikes Calmodulin Cell membrane Cells Code Complement Complex Coupling Cyclic AMP Cyclic GMP Cyclic Nucleotides Cytosol Defect Electrophysiology (science)Eukaryota Female Fertilization Genetic Growth Health Heart failure Human Hyphae Image Immune System Diseases Immune response Immunity Knowledge Laboratories Laboratory Study Link Malignant Neoplasms Medical Metabolic Diseases Modeling Names Natural Immunity Neurodegenerative Disorders Nucleotides Pathway interactions Peptide Receptor Peptide Signal Sequences Peptides Phenotype Phosphotransferases Plants Play Pollen Tube Process Proteins Protons Regulation Research Role Saccharomycetales Second Messenger Systems Sequence Analysis Shapes Signal Transduction Specificity Structure-Activity Relationship Testing Translating Whole Organism Work autocrine axon guidance base cell growth cyclic-nucleotide gated ion channels directional cell genetic analysis human disease male mutant pathogenic bacteria peptide hormone polarized cell receptor reconstitution response sensor sperm cell tool yeast genetics

项目摘要

Calcium (Ca) is a second messenger in all eukaryotes. Defects in Ca signaling cause numerous human diseases including Alzheimer’s disease, heart failure, metabolic diseases, immune disorders, neurodegenerative diseases, and cancer. Despite the importance and broad medical implications, Ca signaling mechanisms remain unclear. The challenging question concerns how Ca encodes specific information coming from different primary signals and translate them into distinct cellular responses. Coding and decoding the specificity of Ca signals remains a long-standing puzzle in the signal transduction field. The PI’s laboratory studies Ca coding and decoding mechanisms using Arabidopsis as a model system and has made breakthroughs in dissecting Ca- coding mechanisms, setting the stage for this application. The proposed studies seek to understand Ca-coding mechanisms in the contexts of pollen tube growth and innate immunity both of which involve cyclic nucleotide- gated channels (CNGCs) in Arabidopsis. The Specific Aim 1 will address the relationship between CNGC-based Ca oscillations and peptide signaling during pollen tube growth. PI’s lab identified two CNGC-type proteins and calmodulin (CaM) forming a Ca “oscillator” in pollen tube growth that also requires autocrine peptide hormones produced by pollen tube. The overarching hypothesis is that peptides bind to their receptors that in turn modulate Ca-oscillator channels. This will be tested through genetic analysis combined with single cell Ca imaging. The Specific Aim 2 will identify Ca transporters that work together with CNGCs in immunity signaling. The importance of Ca signaling has long been recognized in innate immunity for both animal and plant cells. PI’s lab identified a CNGC-type channel that generates cytoplasmic Ca spike in response to bacterial pathogens. Using genetic analysis in Arabidopsis and yeast genetic complementation models, Aim 2 will identify the transporters responsible for removing the Ca signal and study how they coordinate with CNGC-type channels to precisely shape the spatial and temporal dynamics of Ca codes. Specific Aim 3 seeks to understand the mechanisms for activation and inactivation of plant CNGCs. The CNGC-type channels function in both pollen tube and immunity models, but they consist of different subunits and their regulations by CaM are different too. Further, while animal CNGCs are activated by the cyclic nucleotides (cAMP/cGMP), the plant CNGCs in pollen tube and immunity models are insensitive to these nucleotides. The hypothesis is that plant CNGCs are regulated differently from animal counterparts and CaM-based regulation depends on subunit composition of the CNGCs. This hypothesis will be tested in Aim 3 using biochemical and electrophysiological approaches in both pollen tube and immunity model. Arabidopsis is an ideal model to address basic Ca signaling mechanisms, as it provides a plethora of genetic tools and an array of whole-organism and single-cell Ca signaling phenotypes in the genetic mutants. Completion of these aims will reveal new Ca coding mechanisms, contributing to the conceptual framework of Ca signaling highly relevant to human health.

钙 (Ca) 是所有真核生物中的第二信使，Ca 信号传导缺陷会导致多种人类疾病。包括阿尔茨海默病、心力衰竭、代谢疾病、免疫疾病、神经退行性疾病尽管钙信号传导机制具有重要意义和广泛的医学意义，但它仍然存在。尚不清楚，具有挑战性的问题涉及 Ca 如何编码来自不同初级的特定信息。信号并将其转化为不同的细胞反应，编码和解码 Ca 信号的特异性。 PI 实验室研究 Ca 编码和信号转导领域长期存在的难题。使用拟南芥作为模型系统的解码机制，并在解剖 Ca- 方面取得了突破编码机制，为该应用奠定了基础。拟议的研究旨在理解 Ca 编码。花粉管生长和先天免疫背景下的机制都涉及环核苷酸- 拟南芥中的门控通道（CNGC）具体目标 1 将解决基于 CNGC 之间的关系。 PI 的实验室鉴定了两种 CNGC 型蛋白质和花粉管生长过程中的 Ca 振荡和肽信号传导。钙调蛋白 (CaM) 在花粉管生长过程中形成 Ca“振荡器”，也需要自分泌肽激素总体假设是肽与其受体结合，进而调节。 Ca 振荡器通道将通过遗传分析结合单细胞 Ca 成像进行测试。具体目标 2 将确定与 CNGC 一起发挥作用的 Ca 转运蛋白在免疫信号传导中的重要性。长期以来，PI 的实验室在动物和植物细胞的先天免疫中发现了 Ca 信号传导。 CNGC 型通道利用基因产生胞质 Ca 尖峰以响应细菌病原体。在拟南芥和酵母遗传互补模型中进行分析，目标 2 将识别转运蛋白负责去除 Ca 信号并研究它们如何与 CNGC 型通道协调以精确地具体目标 3 旨在了解 Ca 代码的空间和时间动态。 CNGC 型通道在花粉管和免疫中发挥作用。模型，但它们由不同的亚基组成，并且 CaM 的调节也不同。此外，而动物。 CNGCs被环核苷酸(cAMP/cGMP)、花粉管中的植物CNGCs和免疫激活模型对这些核苷酸不敏感，假设植物 CNGC 的调控方式与植物 CNGC 不同。动物单位和基于 CaM 的调节取决于 CNGC 的亚单位组成。将在目标 3 中使用生化和电生理学方法对花粉管和免疫进行测试拟南芥是解决基本 Ca 信号传导机制的理想模型，因为它提供了大量的遗传工具以及基因突变体中一系列整个生物体和单细胞 Ca 信号传导表型。完成这些目标将揭示新的 Ca 编码机制，有助于构建 Ca 信号传导与人类健康高度相关。