Structure and Function of Ocular Lacritin

眼泪素的结构和功能

• 批准号: 8116487
• 负责人: Gordon William Laurie
• 金额: $ 35.07万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8116487
• 关键词: AQP1 gene; Acinar Cell; Address; Adverse effects; Agonist; Anti-Inflammatory Agents; Binding; Biological Assay; Blepharitis; Calcineurin; Calcineurin inhibitor; Calcium; Calcium Signaling; Carbachol; Cell Culture Techniques; Cell Proliferation; Cell physiology; Cell surface; Complex; Contact Lenses; Cornea; Crystallins; Cyclosporine; Distal; Dose; Down-Regulation; Drug Design; Drug Prescriptions; Dry Eye Syndromes; Elements; Epithelial; Epithelial Cells; Epithelium; Event; Eye; Eye diseases; Female; G Protein-Coupled Receptor Genes; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Goals; Golgi Apparatus; Health; Heart; Human; INS 365; Insulin; Lacrimal gland structure; Ligation; Lung; Membrane; MicroRNAs; Molecular; Monkeys; Muramidase; Mutation; Oryctolagus cuniculus; Pancreas; Pathway interactions; Patients; Peroxidases; Pharmaceutical Preparations; Phosphotransferases; Production; Proliferating; Protein Phosphatase G; Proteins; Proteoglycan; RNA Splicing; Rattus; Receptor Signaling; Research; Role; STIM1 gene; Secretory Vesicles; Serum; Signal Transduction; Small Interfering RNA; Structure; T-Lymphocyte; Therapeutic; Treatment Protocols; Up-Regulation; Variant; Work; analog; base; cell type; corneal epithelium; eye dryness; feeding; heparanase; human FRAP1 protein; lacrimal; meibomian gland; novel; ocular surface; protein protein interaction; receptor; small molecule; syndecan; tear proteins

DESCRIPTION (provided by applicant): Our competitive renewal application addresses dry eye from the perspective of the new ocular-specific tear factor 'lacritin' discovered by us. Lacritin flows onto the ocular surface from lacrimal and meibomian glands to help promote ocular surface wetting. It is also a presumed contributor to corneal renewal via its basal corneal epithelial expression. Selective downregulation of lacritin in tears is associated with blepharitis and contact lens-related dry eye, the only two dry eye syndromes proteomically examined to date. Adding lacritin to eyes of normal rabbits or dry eye female monkeys ovariectomized one to two years earlier triggers elevated and sustained tear flow. These observations are reinforced by human corneal epithelial cell culture in which lacritin stimulates MUC16 protein production more efficiently than serum and by our original observation that lacritin augments tear peroxidase release from cultured rat lacrimal acinar cells independent of the parasympathetic- (carbachol-) stimulation pathway. Also subconfluent cultures of human corneal epithelial cells proliferate in a lacritin domain- and dose-specific manner. How lacritin promotes tearing and renewal is not understood. Our lacritin structure/function and lacritin signaling studies have sketched out a heparanase-dependent mechanism for targeting cell surface proteoglycan syndecan-1. This leads to putative ligation of a G-protein coupled receptor for signaling through G1i or G1o to PLC-PKC1/PLD/mTOR and PLC- PKC1/STIM1/calcineurin/Ca2+/ NFATC1. Differential upregulation of newly identified splice variants lacritin-b or -c (suspected to be incapable of respectively binding the GPCR or syndecan-1) coincident with downregulation of native lacritin, or loss of heparanase (observed preliminarily in dry eye tears) are two potential dry eye-provoking scenarios. Our working hypothesis is that lacritin is a regulator of ocular surface wetting and renewal. Our immediate goal is to characterize the signaling receptor and understand its mechanism of action. Our first aim is to understand specific protein-protein interactions constituting the lacritin/syndecan-1/G-protein coupled receptor heterocomplex. Our second aim is to characterize how upstream lacritin signaling is generated. Our third aim asks how downstream lacritin signaling can promote wetting and renewal towards a global appreciation for lacritin's role on the ocular surface. PUBLIC HEALTH RELEVANCE. Dry eye is very common. This project will work out how a new potential therapeutic for dry eye promotes ocular surface wetting. The therapeutic is based on a natural human tear protein.

描述（由申请人提供）： 我们的竞争性更新申请从我们发现的新的眼部特异性泪液因子“lacritin”的角度解决干眼症。泪腺素从泪腺和睑板腺流到眼表上，以帮助促进眼表湿润。它也是通过其基底角膜上皮表达的角膜更新的假定贡献者。泪液中催泪蛋白的选择性下调与睑缘炎和隐形眼镜相关干眼有关，这是迄今为止仅有的两种干眼综合征蛋白质组学研究。在正常兔子或一两年前切除卵巢的干眼症雌性猴子的眼睛中加入催泪素，会引起泪液流量的增加和持续。这些观察结果得到了人角膜上皮细胞培养，其中催泪素刺激MUC 16蛋白的产生比血清更有效，并通过我们最初的观察，催泪素增加泪液过氧化物酶从培养的大鼠泪腺泡细胞的释放独立的副交感神经（卡巴胆碱）刺激途径。人角膜上皮细胞的亚融合培养物也以催乳素结构域和剂量特异性方式增殖。催泪素如何促进撕裂和更新尚不清楚。我们的催乳素结构/功能和催乳素信号转导研究已经勾勒出了靶向细胞表面蛋白聚糖syndecan-1的乙酰肝素酶依赖性机制。这导致用于通过Gli或Glo进行信号传导的G蛋白偶联受体与PLC-PKC 1/PLD/mTOR和PLC-PKC 1/STIM 1/钙调磷酸酶/Ca 2 +/NFATC 1的推定连接。新鉴定的剪接变体乳蛋白-b或-c（怀疑不能分别结合GPCR或多配体蛋白聚糖-1）的差异上调与天然乳蛋白的下调或乙酰肝素酶的损失（初步在干眼泪液中观察到）一致，是两种潜在的引起干眼的情况。我们的工作假设是，催泪蛋白是眼表湿润和更新的调节剂。我们的近期目标是表征信号受体并了解其作用机制。我们的第一个目标是了解特定的蛋白质-蛋白质相互作用构成的lacritin/syndecan-1/G-蛋白偶联受体异源复合物。我们的第二个目标是描述上游lacritin信号是如何产生的。我们的第三个目标是询问下游催泪蛋白信号传导如何促进湿润和更新，以全面了解催泪蛋白在眼表的作用。 公共卫生相关性。干眼症很常见。这个项目将研究一种新的潜在的干眼治疗方法如何促进眼表湿润。该治疗剂基于天然的人类泪液蛋白。

项目成果

Targeting of heparanase-modified syndecan-1 by prosecretory mitogen lacritin requires conserved core GAGAL plus heparan and chondroitin sulfate as a novel hybrid binding site that enhances selectivity.

原分泌促分裂原乳泌素靶向乙酰肝素酶修饰的 Syndecan-1 需要保守的核心 GAGAL 加上乙酰肝素和硫酸软骨素作为新的混合结合位点，以增强选择性。

• DOI: 10.1074/jbc.m112.422717
• 发表时间: 2013
• 期刊: The Journal of biological chemistry
• 作者: Zhang,Yinghui;Wang,Ningning;Raab,RonaldW;McKown,RobertL;Irwin,JacobA;Kwon,Inchan;vanKuppevelt,ToinH;Laurie,GordonW
• 通讯作者: Laurie,GordonW

Detection of prosecretory mitogen lacritin in nonprimate tears primarily as a C-terminal-like fragment.

检测非灵长类泪液中主要作为 C 末端片段的促分泌性乳泌素。

• DOI: 10.1167/iovs.11-8567
• 发表时间: 2012
• 期刊: Investigative ophthalmology & visual science
• 影响因子: 4.4
• 作者: Laurie,DianeE;Splan,RebeccaK;Green,Kari;Still,KatherineM;McKown,RobertL;Laurie,GordonW
• 通讯作者: Laurie,GordonW

Focus on molecules: heparanase.

• DOI: 10.1016/j.exer.2010.05.004
• 发表时间: 2010-10
• 期刊: EXPERIMENTAL EYE RESEARCH
• 影响因子: 3.4
• 作者: Zhang, Yinghui;Ryan, Denise S.;Bower, Kraig S.;Ilan, Neta;Vlodavsky, Israel;Laurie, Gordon W.
• 通讯作者: Laurie, Gordon W.

Development of lacrimal gland inflammation in the mouse model of herpes stromal keratitis.

疱疹基质角膜炎小鼠模型泪腺炎症的发展。

• DOI: 10.1016/j.exer.2019.04.022
• 发表时间: 2019
• 期刊: Experimental eye research
• 影响因子: 3.4
• 作者: Rao,Pushpa;McKown,RobertL;Laurie,GordonW;Suvas,Susmit
• 通讯作者: Suvas,Susmit

Conserved regional 3' grouping of rare codons in the coding sequence of ocular prosecretory mitogen lacritin.

眼促促细胞分裂原乳泌素编码序列中稀有密码子的保守区域 3 分组。

• DOI: 10.1167/iovs.12-10740
• 发表时间: 2013
• 期刊: Investigative ophthalmology & visual science
• 影响因子: 4.4
• 作者: McKown,RobertL;Raab,RonaldW;Kachelries,Patricia;Caldwell,Sara;Laurie,GordonW
• 通讯作者: Laurie,GordonW