权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Role of Aquaporin-0 for cell-to-cell adhesion and lens transparency

Aquaporin-0 在细胞间粘附和晶状体透明度方面的作用

基本信息

批准号：
8494216
负责人：
Kulandaiappan Varadaraj
金额：
$ 7.5万
依托单位：
STATE UNIVERSITY NEW YORK STONY BROOK
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-04-01 至 2014-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8494216
关键词：
Accounting Adhesions Aging-Related Process Amino Acids Animal Model Architecture Binding Biochemical Biological Blinded Blindness Calmodulin Cataract Categories Cell Adhesion Cell Adhesion Molecules Cell Aging Cells Charge Chimera organism Cleaved cell Computers Data Development Disease Drug Compounding Engineering Goals Homeostasis Human In Vitro Integral Membrane Protein Investigation Knock-in Mouse Knock-out Knockout Mice L Cells Lens Fiber Literature MIP gene Methods Missense Mutation Modeling Molecular Mus Mutagenesis Mutate Mutation Outcome Permeability Play Prevention Proteins Role Senile Cataract Site Site-Directed Mutagenesis Structural Protein Structure Testing Therapeutic Tissues Transgenic Organisms Tyrosine United States Vision Water Xenopus oocyte age related base cell age cytotoxicity design extracellular falls fiber cell improved in vivo insight lens lens transparency monomer mouse model mutant novel promoter protein expression protein misfolding public health relevance research study restoration simulation water channel

项目摘要

DESCRIPTION (provided by applicant): Lens is a transparent tissue that lacks vasculature. Transmembrane water channels known as aquaporins (AQPs) play a significant role in maintaining transparency and homeostasis in the avascular lens. Mutations in AQP0 result in lens cataract in both human and mouse; knockout leads to cataract in mouse. Our long term goal is to contribute to the treatment and prevention of lens cataract. In this proposal, we are directing our focus on AQP0. At least two functions have been attributed for AQP0 viz., water permeability and cell-to-cell adhesion. Water permeability has been proven authentically through in vitro and in vivo studies while cell-to-cell adhesion function remains hypothetical; moreover, it is controversial whether intact as well as cleaved forms of AQP0 function both as a water pore and a cell-to-cell adhesion protein. The goals of this proposal is to critically experiment and clearly define whether AQP0 functions as a cell-to-cell adhesion protein, whether intact as well as the N- or and C- terminus cleaved forms function both as a water pore and a cell-to-cell adhesion protein (Aim 1), whether the extracellular loops play a critical role in cell-to-cell adhesion (Aim 2), whether the calmodulin-binding domain has a role with regard to adhesion function (Aim 3) and whether the function/s of AQP0 can be replaced by knocking in AQP4 which is proven to have both water permeability and cell-to-cell adhesion function (Aim 4). A novel method developed will be used to study the cell-to-cell adhesion function of the different forms of AQP0. Involvement of extracellular loop in cell-to-cell adhesion and the role of calmodulin binding domain for the functions of AQP0 will be studied using site-directed mutagenesis and PCR-based domain swapping. Computer based molecular simulation will be performed as necessary for mutagenesis studies. Knock-in animal models will be developed to test the in vivo outcome of the in vitro findings. The objectives will be pursued using structure-function approach and performing cytological, biochemical and molecular biological experiments as appropriate to verify the results. PUBLIC HEALTH RELEVANCE: Lens cataract is responsible for majority of the loss of sight in the United States and ranks #1 globally with over 20 million people around the world already blinded and an additional 1.25 million added to the total each year; age-related cataract by itself accounts for more than 48% of loss of vision scenarios. Lens cataract caused by AQP0 falls in the category of conformational diseases (proteopathies) as they are mainly caused by missense mutations or age related protein misfolding, aggregation and cytotoxicity and main goal of this project is to provide new insights into the structure-related functional roles of AQP0, the most abundant integral membrane protein in the lens, for maintaining transparency and homeostasis. This investigation will contribute to an improved understanding of normal lens development and aging processes, and help to design and develop therapeutic compounds/drugs for congenital and senile cataracts in humans.

描述(申请人提供)：晶状体是一种透明的组织，缺乏血管系统。跨膜水通道，称为水通道蛋白(AQPs)，在维持无血管晶状体的透明度和动态平衡方面发挥着重要作用。AQP0基因突变导致人类和小鼠晶状体白内障；基因敲除导致小鼠白内障。我们的长期目标是为晶状体白内障的治疗和预防做出贡献。在这项提案中，我们将重点放在AQP0上。AQP0至少有两个功能，即透水性和细胞间黏附。体外和体内研究已经证实了AQP0的透水性，但细胞与细胞间的黏附功能仍是一个假说；此外，AQP0的完整和裂解形式是否同时具有水孔和细胞间黏附蛋白的功能仍存在争议。这项建议的目标是进行关键实验并明确确定AQP0是否作为细胞间黏附蛋白发挥功能，是否完整以及N-或和C-末端裂解形式是否同时作为水孔和细胞间黏附蛋白(目标1)，细胞外环是否在细胞间黏附中发挥关键作用(目标2)。钙调蛋白结合域是否具有与黏附功能有关的作用(目标3)以及是否可以通过敲打既具有透水性又具有细胞间黏附功能的AQP4来取代AQP0的功能(AQP4)(目标4)。一种新开发的方法将被用来研究不同形式的AQP0的细胞间黏附功能。细胞外环参与细胞间黏附以及钙调蛋白结合域在AQP0功能中的作用将通过定点突变和基于PCR的结构域交换来研究。根据诱变研究的需要，将进行基于计算机的分子模拟。将建立敲入动物模型来测试体外发现的体内结果。将使用结构-功能方法来实现这些目标，并酌情进行细胞学、生化和分子生物学实验来验证结果。公共卫生相关性：晶状体白内障是美国大部分失明的原因，在全球排名第一，全世界有2000多万人失明，每年新增125万人；年龄相关性白内障本身就占失明情况的48%以上。由AQP0引起的晶状体白内障属于构象疾病(蛋白质病)的范畴，因为它们主要是由错义突变或年龄相关的蛋白质错误折叠、聚集和细胞毒性引起的，本项目的主要目的是为研究AQP0的结构相关功能提供新的见解，AQP0是晶状体中含量最丰富的完整膜蛋白，用于维持透明和内稳。这项研究将有助于更好地了解晶状体的正常发育和衰老过程，并有助于设计和开发治疗人类先天性和老年性白内障的化合物/药物。

项目成果

期刊论文数量（11）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Intact and N- or C-terminal end truncated AQP0 function as open water channels and cell-to-cell adhesion proteins: end truncation could be a prelude for adjusting the refractive index of the lens to prevent spherical aberration.

DOI：
10.1016/j.bbagen.2014.05.002
发表时间：
2014-09
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS
影响因子：
3
作者：
Kumari, S. Sindhu;Varadaraj, Kulandaiappan
通讯作者：
Varadaraj, Kulandaiappan

Deletion of beaded filament proteins or the C-terminal end of Aquaporin 0 causes analogous abnormal distortion aberrations in mouse lens.

DOI：
10.1016/j.exer.2021.108645
发表时间：
2021-08
期刊：
EXPERIMENTAL EYE RESEARCH
影响因子：
3.4
作者：
Varadaraj, Kulandaiappan;FitzGerald, Paul G.;Kumari, S. Sindhu
通讯作者：
Kumari, S. Sindhu

Positively charged amino acid residues in the extracellular loops A and C of lens aquaporin 0 interact with the negative charges in the plasma membrane to facilitate cell-to-cell adhesion.

晶状体水通道蛋白 0 的细胞外环 A 和 C 中带正电荷的氨基酸残基与质膜中的负电荷相互作用，以促进细胞间粘附。

DOI：
10.1016/j.exer.2019.05.022
发表时间：
2019
期刊：
Experimental eye research
影响因子：
3.4
作者：
Kumari,Sindhu;Taginik,Gozde;Varadaraj,Sangeeth;Varadaraj,Kulandaiappan
通讯作者：
Varadaraj,Kulandaiappan

Functional characterization of an AQP0 missense mutation, R33C, that causes dominant congenital lens cataract, reveals impaired cell-to-cell adhesion.

DOI：
10.1016/j.exer.2013.09.019
发表时间：
2013-11
期刊：
EXPERIMENTAL EYE RESEARCH
影响因子：
3.4
作者：
Kumari, Sindhu S.;Gandhi, Jason;Mustehsan, Mohammed H.;Eren, Semih;Varadaraj, Kulandaiappan
通讯作者：
Varadaraj, Kulandaiappan

Aquaporin 0 plays a pivotal role in refractive index gradient development in mammalian eye lens to prevent spherical aberration.