Platelet granule formation and function in health and disease

血小板颗粒的形成及其在健康和疾病中的功能

• 批准号: 9257459
• 负责人: Michael S Marks
• 金额: $ 47.56万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-07 至 2020-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9257459
• 关键词: Adhesions; Affect; Alpha Granule; Biogenesis; Blood Coagulation Disorders; Blood Platelet Disorders; Blood Platelets; Blood Vessels; Bone Marrow; Calcium; Cell membrane; Cells; Chimeric Proteins; Coagulation Process; Complex; Cytoplasmic Granules; Data; Defect; Diagnostic; Disease; Disease susceptibility; Early Endosome; Endosomes; Epitopes; Fetal Liver; Genes; Health; Hemorrhage; Hemorrhagic Disorders; Hemostatic function; Hereditary Disease; Hermanski-Pudlak Syndrome; Human; Impairment; In Situ; Inflammation; Integral Membrane Protein; Label; Lysosomes; Megakaryocytes; Melanosomes; Membrane; Membrane Proteins; Modeling; Molecular; Morphology; Mus; Oculocutaneous Albinism; Organelles; Pathology; Pathway interactions; Patients; Pharmacology; Phenotype; Pigments; Process; Proteins; Quinacrine; Role; Secondary to; Serotonin; Sorting - Cell Movement; Source; Structure; Testing; Therapeutic; Therapeutic Intervention; Thrombus; Tissues; Transport Process; Variant; Vesicle; Vesicle Transport Pathway; Wound Healing; angiogenesis; base; cell type; cohort; functional disability; improved; in vivo; induced pluripotent stem cell; insight; melanocyte; mouse model; protein complex; public health relevance; reconstitution; small molecule; tool

DESCRIPTION (provided by applicant): Platelets fulfill essential functions in hemostasis, inflammation, angiogenesis, and other processes. Many of these functions require regulated secretion from three types of storage compartments - � granules, dense granules, and lysosomes. Many hemorrhagic and thrombotic disorders are caused by dysregulation of granule formation and/or content release. In particular, bleeding diathesis in Hermansky-Pudlak syndrome (HPS) results from an absence of detectable platelet dense granules and consequent defects in activation-dependent release of calcium and ADP, which normally promote thrombus formation. Despite the importance of platelet granules, the mechanisms underlying their formation and membrane dynamics within megakaryocytes (MKs) and/or their derived platelets are largely uncharacterized, and the pathways regulated by the genes that are defective in the nine characterized HPS variants are not known. In other cell types, HPS-associated genes regulate vesicular transport processes required to deliver resident integral membrane proteins from early endosomes to lysosome-related organelles - cell type-specific intracellular storage compartments like � and dense granules. We and our collaborators have recently identified two integral membrane proteins - SLC35D3 and VMAT2 - as candidate dense granule-specific cargoes that can serve as markers to study dense granule biogenesis. Surprisingly, these two cargoes localize to early endosomes in MKs from both wild-type and HPS model mice. Nevertheless, SLC35D3 is destabilized in platelets from the same HPS models. Based on these and other data, we hypothesize that dense granule integral membrane proteins are delivered from early endosomes to immature dense granules at a late stage of differentiation of platelets from MKs. We further hypothesize that dense granule membranes are not static but are constantly remodeled in active platelets, perhaps providing an avenue for delivery of pharmacological agents to platelet dense granules. Finally, preliminary data suggest that activation-induced content release is impaired not only from dense granules but also from � granules and lysosomes in HPS model platelets, both in vivo and ex vivo. Since content release requires fusion of the granule membrane with the plasma membrane, we hypothesize that this secretory defect in HPS models reflects impaired cargo delivery of the fusion machinery to � granules and lysosomes. We will test these hypotheses in the following Specific Aims: 1. To assess whether HPS-associated proteins regulate the dynamic localization of candidate dense granule membrane proteins in platelets. 2. To assess whether HPS impacts maturation of dense granules by fusion of distinct precursor organelles. 3. To test whether and how HPS subtypes impact �-granule and lysosome secretion from platelets.

描述（由申请人提供）：血小板在止血、炎症、血管生成和其他过程中发挥重要功能。其中许多功能需要三种类型储存室的调节分泌——颗粒、致密颗粒和溶酶体。许多出血性和血栓性疾病是由颗粒形成和/或内容物释放失调引起的。特别是，赫曼斯基-普德拉克综合征 (HPS) 的出血素质是由于缺乏可检测到的血小板致密颗粒以及随之而来的钙和 ADP 激活依赖性释放缺陷所致，而钙和 ADP 通常会促进血栓形成。尽管血小板颗粒很重要，但巨核细胞 (MK) 和/或其衍生血小板内其形成和膜动力学的机制在很大程度上尚未被表征，并且九种特征性 HPS 变体中缺陷基因所调节的途径尚不清楚。在其他细胞类型中，HPS 相关基因调节囊泡运输过程，将常驻的完整膜蛋白从早期内体传递到溶酶体相关的细胞器（细胞类型特异性的细胞内储存室，如颗粒和致密颗粒）。我们和我们的合作者最近发现了两种完整的膜蛋白 - SLC35D3 和 VMAT2 - 作为候选致密颗粒特异性货物，可以作为研究致密颗粒生物发生的标记。令人惊讶的是，这两种货物定位于野生型和 HPS 模型小鼠 MK 的早期内体。然而，SLC35D3 在来自相同 HPS 模型的血小板中不稳定。基于这些和其他数据，我们假设致密颗粒整合膜蛋白在血小板从 MK 分化的后期从早期内体传递到未成熟的致密颗粒。我们进一步假设致密颗粒膜不是静态的，而是在活性血小板中不断重塑，这可能为将药物递送至血小板致密颗粒提供了途径。最后，初步数据表明，激活诱导的内容物释放不仅受到致密颗粒的损害，而且受到 HPS 模型血小板中颗粒和溶酶体的损害，无论是在体内还是离体。由于内容物的释放需要颗粒膜与质膜的融合，我们假设 HPS 模型中的这种分泌缺陷反映了融合机制向颗粒和溶酶体的货物输送受损。我们将在以下具体目标中测试这些假设： 1. 评估 HPS 相关蛋白是否调节候选致密颗粒膜蛋白在血小板中的动态定位。 2. 评估 HPS 是否通过不同前体细胞器的融合影响致密颗粒的成熟。 3. 测试 HPS 亚型是否以及如何影响血小板的β颗粒和溶酶体分泌。

项目成果

Tyrosine 870 of TLR9 is critical for receptor maturation rather than phosphorylation-dependent ligand-induced signaling.

• DOI: 10.1371/journal.pone.0200913
• 发表时间: 2018
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Biswas C;Rao S;Slade K;Hyman D;Dersh D;Mantegazza AR;Zoltick PW;Marks MS;Argon Y;Behrens EM
• 通讯作者: Behrens EM

Pink Light on Mitochondria in Autoimmunity and Parkinson Disease.

自身免疫和帕金森病线粒体上的粉红光。

• DOI: 10.1016/j.cmet.2016.06.022
• 发表时间: 2016
• 期刊: Cell metabolism
• 影响因子: 29
• 作者: Mantegazza,AdrianaR;Marks,MichaelS
• 通讯作者: Marks,MichaelS