1
|
O'Donoghue L, Smolenski A. Roles of G proteins and their GTPase-activating proteins in platelets. Biosci Rep 2024; 44:BSR20231420. [PMID: 38808367 PMCID: PMC11139668 DOI: 10.1042/bsr20231420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 05/30/2024] Open
Abstract
Platelets are small anucleate blood cells supporting vascular function. They circulate in a quiescent state monitoring the vasculature for injuries. Platelets adhere to injury sites and can be rapidly activated to secrete granules and to form platelet/platelet aggregates. These responses are controlled by signalling networks that include G proteins and their regulatory guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Recent proteomics studies have revealed the complete spectrum of G proteins, GEFs, and GAPs present in platelets. Some of these proteins are specific for platelets and very few have been characterised in detail. GEFs and GAPs play a major role in setting local levels of active GTP-bound G proteins in response to activating and inhibitory signals encountered by platelets. Thus, GEFs and GAPs are highly regulated themselves and appear to integrate G protein regulation with other cellular processes. This review focuses on GAPs of small G proteins of the Arf, Rab, Ras, and Rho families, as well as of heterotrimeric G proteins found in platelets.
Collapse
Affiliation(s)
- Lorna O'Donoghue
- UCD School of Medicine, University College Dublin, UCD Conway Institute, Belfield, Dublin 4, Ireland
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, 123 St. Stephen’s Green 123, Dublin 2, Ireland
| | - Albert Smolenski
- UCD School of Medicine, University College Dublin, UCD Conway Institute, Belfield, Dublin 4, Ireland
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, 123 St. Stephen’s Green 123, Dublin 2, Ireland
| |
Collapse
|
2
|
Lecaudey LA, Netzer R, Wibberg D, Busche T, Bloecher N. Metatranscriptome analysis reveals the putative venom toxin repertoire of the biofouling hydroid Ectopleura larynx. Toxicon 2024; 237:107556. [PMID: 38072317 DOI: 10.1016/j.toxicon.2023.107556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023]
Abstract
Cnidarians thriving in biofouling communities on aquaculture net pens represent a significant health risk for farmed finfish due to their stinging cells. The toxins coming into contact with the fish, during net cleaning, can adversely affect their behavior, welfare, and survival, with a particularly serious health risk for the gills, causing direct tissue damage such as formation of thrombi and increasing risks of secondary infections. The hydroid Ectopleura larynx is one of the most common fouling organisms in Northern Europe. However, despite its significant economic, environmental, and operational impact on finfish aquaculture, biological information on this species is scarce and its venom composition has never been investigated. In this study, we generated a whole transcriptome of E. larynx, and identified its putative expressed venom toxin proteins (predicted toxin proteins, not functionally characterized) based on in silico transcriptome annotation mining and protein sequence analysis. The results uncovered a broad and diverse repertoire of putative toxin proteins for this hydroid species. Its toxic arsenal appears to include a wide and complex selection of toxin proteins, covering a large panel of potential biological functions that play important roles in envenomation. The putative toxins identified in this species, such as neurotoxins, GTPase toxins, metalloprotease toxins, ion channel impairing toxins, hemorrhagic toxins, serine protease toxins, phospholipase toxins, pore-forming toxins, and multifunction toxins may cause various major deleterious effects in prey, predators, and competitors. These results provide valuable new insights into the venom composition of cnidarians, and venomous marine organisms in general, and offer new opportunities for further research into novel and valuable bioactive molecules for medicine, agronomics and biotechnology.
Collapse
Affiliation(s)
| | - Roman Netzer
- SINTEF Ocean, Aquaculture Department, Brattørkaia 17c, 7010, Trondheim, Norway
| | - Daniel Wibberg
- Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany; Medical School OWL, Bielefeld University, Morgenbreede 1, 33615, Bielefeld, Germany
| | - Nina Bloecher
- SINTEF Ocean, Aquaculture Department, Brattørkaia 17c, 7010, Trondheim, Norway
| |
Collapse
|
3
|
Schartz D, Akkipeddi SMK, Rahmani R, Ellens N, Houk C, Kohli GS, Worley L, Welle K, Bhalla T, Mattingly T, Morrell C, Bender MT. Ischemic Stroke Thrombus Perviousness Is Associated with Distinguishable Proteomic Features and Susceptibility to ADAMTS13-Augmented Thrombolysis. AJNR Am J Neuroradiol 2023; 45:22-29. [PMID: 38123915 PMCID: PMC10756583 DOI: 10.3174/ajnr.a8069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/20/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND AND PURPOSE Perviousness is the differential attenuation on CT of an intracranial arterial occlusive thrombus before and after IV contrast administration. While perviousness/permeability has been shown to be related to various clinical outcomes and reflects histopathologic composition, it remains unclear whether perviousness is also associated with differences in proteomic composition. MATERIALS AND METHODS Retrieved clots from 59 patients were evaluated with quantitative mass spectrometry. Proteomic differences between high-perviousness (≥11 HU) and low-perviousness (<11 HU) clots were investigated. Perviousness as a continuous variable was also correlated with protein abundance. Last, an ex vivo lysis assay was performed to investigate the differential susceptibility to tPA, deoxyribonuclease, and ADAMTS13 thrombolysis as a function of perviousness. RESULTS In total, 2790 distinct proteins were identified. Thrombus perviousness was associated with distinct proteomic features, including depletion of the macrophage marker CD14 (P = .039, z = 1.176) and hemoglobin subunit ζ (P = .046, z = 1.68) in pervious clots. Additionally, proteins involved in platelet cytoskeleton remodeling (tropomyosin α-3-chain) and granule secretion/aggregation (synaptotagmin-like protein 4/FC region receptor II-a) were associated with increasing perviousness (P < .006), among numerous other proteins. Monocyte/macrophage-associated proteins (apoptosis-associated specklike protein containing a CARD/SAMHD1) were also depleted in pervious emboli (P < .002). Ex vivo lysis indicated that pervious clots were more susceptible to ADAMTS13-augmented tPA thrombolysis compared with impervious clots (P < .05), though without differences in deoxyribonuclease digestion. CONCLUSIONS Thrombus perviousness is associated with complex proteomic features, including differential abundance of platelet-related proteins in highly permeable clots with monocyte/macrophage depletion. This association may help to explain why highly pervious thrombi were also found more susceptible to ADAMTS13-augmented thrombolysis.
Collapse
Affiliation(s)
- Derrek Schartz
- From the Department of Imaging Sciences (D.S., L.W.), University of Rochester Medical Center, Rochester, New York
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Sajal Medha K Akkipeddi
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Redi Rahmani
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Nathaniel Ellens
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Clifton Houk
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Gurkirat Singh Kohli
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Logan Worley
- From the Department of Imaging Sciences (D.S., L.W.), University of Rochester Medical Center, Rochester, New York
| | - Kevin Welle
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Tarun Bhalla
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Thomas Mattingly
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| | - Craig Morrell
- Aab Cardiovascular Research Institute (C.M.), University of Rochester Medical Center, Rochester, New York
| | - Matthew T Bender
- Department of Neurosurgery (D.S., S.M.K.A., R.R., N.E., C.H., G.S.K., K.W., T.B., T.M., M.T.B.), University of Rochester Medical Center, Rochester, New York
| |
Collapse
|
4
|
Liang H, Zhang L, Zhao X, Rong J. The therapeutic potential of exosomes in lung cancer. Cell Oncol (Dordr) 2023; 46:1181-1212. [PMID: 37365450 DOI: 10.1007/s13402-023-00815-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2023] [Indexed: 06/28/2023] Open
Abstract
BACKGROUND Lung cancer (LC) is one of the most common malignancies globally. Besides early detection and surgical resection, there is currently no effective curative treatment for metastatic advanced LC. Exosomes are endogenous nano-extracellular vesicles produced by somatic cells that play an important role in the development and maintenance of normal physiology. Exosomes can carry proteins, peptides, lipids, nucleic acids, and various small molecules for intra- and intercellular material transport or signal transduction. LC cells can maintain their survival, proliferation, migration, invasion, and metastasis, by producing or interacting with exosomes. Basic and clinical data also show that exosomes can be used to suppress LC cell proliferation and viability, induce apoptosis, and enhance treatment sensitivity. Due to the high stability and target specificity, good biocompatibility, and low immunogenicity of exosomes, they show promise as vehicles of LC therapy. CONCLUSION We have written this comprehensive review to communicate the LC treatment potential of exosomes and their underlying molecular mechanisms. We found that overall, LC cells can exchange substances or crosstalk with themselves or various other cells in the surrounding TME or distant organs through exosomes. Through this, they can modulate their survival, proliferation, stemness, migration, and invasion, EMT, metastasis, and apoptotic resistance.
Collapse
Affiliation(s)
- Hongyuan Liang
- Department of Radiology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Shenyang, 110004, China
| | - Lingyun Zhang
- Department of Medical Oncology, the First Hospital of China Medical University, No. 210, BaiTa Street, Hunnan District, Shenyang, 110001, People's Republic of China
| | - Xiangxuan Zhao
- Health Sciences Institute, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, 110022, People's Republic of China.
| | - Jian Rong
- Department of Pediatrics, PICU, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Shenyang, Liaoning Province, 110004, People's Republic of China.
| |
Collapse
|
5
|
Harper MT. Platelet-Derived Extracellular Vesicles in Arterial Thrombosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1418:259-275. [PMID: 37603285 DOI: 10.1007/978-981-99-1443-2_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
Blood platelets are necessary for normal haemostasis but also form life-threatening arterial thrombi when atherosclerotic plaques rupture. Activated platelets release many extracellular vesicles during thrombosis. Phosphatidylserine-exposing microparticles promote coagulation. Small exosomes released during granule secretion deliver cargoes including microRNAs to cells throughout the cardiovascular system. Here, we discuss the mechanisms by which platelets release these extracellular vesicles, together with the possibility of inhibiting this release as an antithrombotic strategy.
Collapse
Affiliation(s)
- Matthew T Harper
- Department of Pharmacology, University of Cambridge, Cambridge, UK.
| |
Collapse
|
6
|
Izumi T. In vivo Roles of Rab27 and Its Effectors in Exocytosis. Cell Struct Funct 2021; 46:79-94. [PMID: 34483204 PMCID: PMC10511049 DOI: 10.1247/csf.21043] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 08/31/2021] [Indexed: 11/11/2022] Open
Abstract
The monomeric GTPase Rab27 regulates exocytosis of a broad range of vesicles in multicellular organisms. Several effectors bind GTP-bound Rab27a and/or Rab27b on secretory vesicles to execute a series of exocytic steps, such as vesicle maturation, movement along microtubules, anchoring within the peripheral F-actin network, and tethering to the plasma membrane, via interactions with specific proteins and membrane lipids in a local milieu. Although Rab27 effectors generally promote exocytosis, they can also temporarily restrict it when they are involved in the rate-limiting step. Genetic alterations in Rab27-related molecules cause discrete diseases manifesting pigment dilution and immunodeficiency, and can also affect common diseases such as diabetes and cancer in complex ways. Although the function and mechanism of action of these effectors have been explored, it is unclear how multiple effectors act in coordination within a cell to regulate the secretory process as a whole. It seems that Rab27 and various effectors constitutively reside on individual vesicles to perform consecutive exocytic steps. The present review describes the unique properties and in vivo roles of the Rab27 system, and the functional relationship among different effectors coexpressed in single cells, with pancreatic beta cells used as an example.Key words: membrane trafficking, regulated exocytosis, insulin granules, pancreatic beta cells.
Collapse
Affiliation(s)
- Tetsuro Izumi
- Laboratory of Molecular Endocrinology and Metabolism, Department of Molecular Medicine, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma 371-8512, Japan
| |
Collapse
|
7
|
Soliman AS, Umstead A, Grabinski T, Kanaan NM, Lee A, Ryan J, Lamp J, Vega IE. EFhd2 brain interactome reveals its association with different cellular and molecular processes. J Neurochem 2021; 159:992-1007. [PMID: 34543436 PMCID: PMC9552186 DOI: 10.1111/jnc.15517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 08/11/2021] [Accepted: 09/09/2021] [Indexed: 01/06/2023]
Abstract
EFhd2 is a conserved calcium-binding protein that is highly expressed in the central nervous system. We have shown that EFhd2 interacts with tau protein, a key pathological hallmark in Alzheimer's disease and related dementias. However, EFhd2's physiological and pathological functions in the brain are still poorly understood. To gain insights into its physiological function, we identified proteins that co-immunoprecipitated with EFhd2 from mouse forebrain and hindbrain, using tandem mass spectrometry (MS). In addition, quantitative mass spectrometry was used to detect protein abundance changes due to the deletion of the Efhd2 gene in mouse forebrain and hindbrain regions. Our data show that mouse EFhd2 is associated with cytoskeleton components, vesicle trafficking modulators, cellular stress response-regulating proteins, and metabolic proteins. Moreover, proteins associated with the cytoskeleton, vesicular transport, calcium signaling, stress response, and metabolic pathways showed differential abundance in Efhd2(-/-) mice. This study presents, for the first time, an EFhd2 brain interactome that it is associated with different cellular and molecular processes. These findings will help prioritize further studies to investigate the mechanisms by which EFhd2 modulates these processes in physiological and pathological conditions of the nervous system.
Collapse
Affiliation(s)
- Ahlam S Soliman
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA.,Neuroscience Program, Michigan State University, Grand Rapids, Michigan, USA.,Department of Clinical Pharmacy and Pharmacy Practice, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Andrew Umstead
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA.,Integrated Mass Spectrometry Unit, College of Human Medicine, Grand Rapids, Michigan, USA
| | - Tessa Grabinski
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
| | - Nicholas M Kanaan
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA.,Neuroscience Program, Michigan State University, Grand Rapids, Michigan, USA.,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, Michigan, USA
| | - Andy Lee
- NeuroInitiatives LLC, Jacksonville, Florida, USA
| | - John Ryan
- NeuroInitiatives LLC, Jacksonville, Florida, USA
| | - Jared Lamp
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA.,Integrated Mass Spectrometry Unit, College of Human Medicine, Grand Rapids, Michigan, USA
| | - Irving E Vega
- Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA.,Neuroscience Program, Michigan State University, Grand Rapids, Michigan, USA.,Integrated Mass Spectrometry Unit, College of Human Medicine, Grand Rapids, Michigan, USA.,Hauenstein Neuroscience Center, Mercy Health Saint Mary's, Grand Rapids, Michigan, USA.,Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|
8
|
Wang H, Lu Z, Zhao X. Tumorigenesis, diagnosis, and therapeutic potential of exosomes in liver cancer. J Hematol Oncol 2019; 12:133. [PMID: 31815633 PMCID: PMC6902437 DOI: 10.1186/s13045-019-0806-6] [Citation(s) in RCA: 152] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/17/2019] [Indexed: 12/24/2022] Open
Abstract
Hepatocellular carcinoma (HCC, also called primary liver cancer) is one of the most fatal cancers in the world. Due to the insidiousness of the onset of HCC and the lack of effective treatment methods, the prognosis of HCC is extremely poor, and the 5-year average survival rate is less than 10%. Exosomes are nano-sized microvesicle and contain various components such as nucleic acids, proteins, and lipids. Exosomes are important carriers for signal transmission or transportation of material from cell to cell or between cells and tissues. In recent years, exosomes have been considered as potential therapeutic targets of HCC. A large number of reports indicate that exosomes play a key role in the establishment of an HCC microenvironment, as well as the development, progression, invasion, metastasis, and even the diagnosis, treatment, and prognosis of HCC. However, the exact molecular mechanisms and roles of exosomes in these processes remain unclear. We believe that elucidation of the regulatory mechanism of HCC-related exosomes and its signaling pathway and analysis of its clinical applications in the diagnosis and treatment of HCC can provide useful clues for future treatment regimens for HCC. This article discusses and summarizes the research progress of HCC-related exosomes and their potential clinical applications.
Collapse
Affiliation(s)
- Hongbo Wang
- Department of Radiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, China
| | - Zaiming Lu
- Department of Radiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, China
| | - Xiangxuan Zhao
- Department of Radiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, China.
| |
Collapse
|
9
|
Wang H, Lu Z, Zhao X. Tumorigenesis, diagnosis, and therapeutic potential of exosomes in liver cancer. J Hematol Oncol 2019; 12:133. [DOI: doi10.1186/s13045-019-0806-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/17/2019] [Indexed: 09/01/2023] Open
Abstract
AbstractHepatocellular carcinoma (HCC, also called primary liver cancer) is one of the most fatal cancers in the world. Due to the insidiousness of the onset of HCC and the lack of effective treatment methods, the prognosis of HCC is extremely poor, and the 5-year average survival rate is less than 10%. Exosomes are nano-sized microvesicle and contain various components such as nucleic acids, proteins, and lipids. Exosomes are important carriers for signal transmission or transportation of material from cell to cell or between cells and tissues. In recent years, exosomes have been considered as potential therapeutic targets of HCC. A large number of reports indicate that exosomes play a key role in the establishment of an HCC microenvironment, as well as the development, progression, invasion, metastasis, and even the diagnosis, treatment, and prognosis of HCC. However, the exact molecular mechanisms and roles of exosomes in these processes remain unclear. We believe that elucidation of the regulatory mechanism of HCC-related exosomes and its signaling pathway and analysis of its clinical applications in the diagnosis and treatment of HCC can provide useful clues for future treatment regimens for HCC. This article discusses and summarizes the research progress of HCC-related exosomes and their potential clinical applications.
Collapse
|
10
|
|
11
|
Unsworth AJ, Bombik I, Pinto-Fernandez A, McGouran JF, Konietzny R, Zahedi RP, Watson SP, Kessler BM, Pears CJ. Human Platelet Protein Ubiquitylation and Changes following GPVI Activation. Thromb Haemost 2018; 119:104-116. [PMID: 30597505 PMCID: PMC6327716 DOI: 10.1055/s-0038-1676344] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Platelet activators stimulate post-translational modification of signalling proteins to change their activity or their molecular interactions leading to signal propagation. One covalent modification is attachment of the small protein ubiquitin to lysine residues in target proteins. Modification by ubiquitin can either target proteins for degradation by the proteasome or act as a scaffold for other proteins. Pharmacological inhibition of deubiquitylases or the proteasome inhibition of platelet activation by collagen, demonstrating a role for ubiquitylation, but relatively few substrates for ubiquitin have been identified and the molecular basis of inhibition is not established. Here, we report the ubiquitome of human platelets and changes in ubiquitylated proteins following stimulation by collagen-related peptide (CRP-XL). Using platelets from six individuals over three independent experiments, we identified 1,634 ubiquitylated peptides derived from 691 proteins, revealing extensive ubiquitylation in resting platelets. Note that 925 of these peptides show an increase of more than twofold following stimulation with CRP-XL. Multiple sites of ubiquitylation were identified on several proteins including Syk, filamin and integrin heterodimer sub-units. This work reveals extensive protein ubiquitylation during activation of human platelets and opens the possibility of novel therapeutic interventions targeting the ubiquitin machinery.
Collapse
Affiliation(s)
- Amanda J Unsworth
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom.,Institute for Cardiovascular and Metabolic Research, University of Reading, Reading, United Kingdom
| | - Izabela Bombik
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Adan Pinto-Fernandez
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - Joanna F McGouran
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - Rebecca Konietzny
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - René P Zahedi
- JGH Proteomics Centre, Lady Davis Institute, Jewish General Hospital, Montreal, Quebec, Canada
| | - Steve P Watson
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom.,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, United Kingdom
| | - Benedikt M Kessler
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, United Kingdom
| | - Catherine J Pears
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
12
|
Abstract
Our understanding of fundamental biological processes within platelets is continually evolving. A critical feature of platelet biology relates to the intricate uptake, packaging and release of bioactive cargo from storage vesicles, essential in mediating a range of classical (haemostasis/thrombosis) and non-classical (regeneration/inflammation/metastasis) roles platelets assume. Pivotal to the molecular control of these vesicle trafficking events are the small GTPases of the Ras superfamily, which function as spatially distinct, molecular switches controlling essential cellular processes. Herein, we specifically focus on members of the Rab, Arf and Ras subfamilies, which comprise over 130 members and platelet proteomic datasets suggest that more than half of these are expressed in human platelets. We provide an update of current literature relating to trafficking roles for these GTPases in platelets, particularly regarding endocytic and exocytic events, but also vesicle biogenesis and provide speculative argument for roles that other related GTPases and regulatory proteins may adopt in platelets. Advances in our understanding of small GTPase function in the anucleate platelet has been hampered by the lack of specific molecular tools, but it is anticipated that this will be greatly accelerated in the years ahead and will be crucial to the identification of novel therapeutic targets controlling different platelet processes.
Collapse
Affiliation(s)
- Tony G Walsh
- a From the School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building , University of Bristol , Bristol , UK
| | - Yong Li
- a From the School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building , University of Bristol , Bristol , UK
| | - Andreas Wersäll
- a From the School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building , University of Bristol , Bristol , UK
| | - Alastair W Poole
- a From the School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building , University of Bristol , Bristol , UK
| |
Collapse
|
13
|
Adam F, Kauskot A, Kurowska M, Goudin N, Munoz I, Bordet JC, Huang JD, Bryckaert M, Fischer A, Borgel D, de Saint Basile G, Christophe OD, Ménasché G. Kinesin-1 Is a New Actor Involved in Platelet Secretion and Thrombus Stability. Arterioscler Thromb Vasc Biol 2018. [PMID: 29519941 DOI: 10.1161/atvbaha.117.310373] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Platelet secretion is crucial for many physiological platelet responses. Even though several regulators of the fusion machinery for secretory granule exocytosis have been identified in platelets, the underlying mechanisms are not yet fully characterized. APPROACH AND RESULTS By studying a mouse model (cKO [conditional knockout]Kif5b) lacking Kif5b (kinesin-1 heavy chain) in its megakaryocytes and platelets, we evidenced unstable hemostasis characterized by an increase of blood loss associated to a marked tendency to rebleed in a tail-clip assay and thrombus instability in an in vivo thrombosis model. This instability was confirmed in vitro in a whole-blood perfusion assay under blood flow conditions. Aggregations induced by thrombin and collagen were also impaired in cKOKif5b platelets. Furthermore, P-selectin exposure, PF4 (platelet factor 4) secretion, and ATP release after thrombin stimulation were impaired in cKOKif5b platelets, highlighting the role of kinesin-1 in α-granule and dense granule secretion. Importantly, exogenous ADP rescued normal thrombin induced-aggregation in cKOKif5b platelets, which indicates that impaired aggregation was because of defective release of ADP and dense granules. Last, we demonstrated that kinesin-1 interacts with the molecular machinery comprising the granule-associated Rab27 (Ras-related protein Rab-27) protein and the Slp4 (synaptotagmin-like protein 4/SYTL4) adaptor protein. CONCLUSIONS Our results indicate that a kinesin-1-dependent process plays a role for platelet function by acting into the mechanism underlying α-granule and dense granule secretion.
Collapse
Affiliation(s)
- Frédéric Adam
- From the INSERM, UMR_S 1176, Paris-Sud University, Université Paris-Saclay, Le Kremlin-Bicêtre, France (F.A., A.K., M.B., D.B., O.D.C.)
| | - Alexandre Kauskot
- From the INSERM, UMR_S 1176, Paris-Sud University, Université Paris-Saclay, Le Kremlin-Bicêtre, France (F.A., A.K., M.B., D.B., O.D.C.)
| | - Mathieu Kurowska
- INSERM, UMR_S 1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France (M.K., I.M., A.F., G.d.S.B., G.M.).,Imagine Institute (M.K., I.M., A.F., G.d.S.B., G.M.)
| | - Nicolas Goudin
- Cell Imaging Facility, Imagine Institute (N.G.), Paris Descartes University, Sorbonne Paris Cité, France
| | - Isabelle Munoz
- INSERM, UMR_S 1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France (M.K., I.M., A.F., G.d.S.B., G.M.).,Imagine Institute (M.K., I.M., A.F., G.d.S.B., G.M.)
| | - Jean-Claude Bordet
- Laboratoire d'Hémostase, Centre de Biologie Est, Hospices Civils de Lyon, Bron, France (J.-C.B.).,Laboratoire de Recherche sur l'Hémophilie, UCBL1, Lyon, France (J.-C.B.)
| | - Jian-Dong Huang
- School of Biomedical Sciences, The University of Hong Kong, China (J.-D.H.)
| | - Marijke Bryckaert
- From the INSERM, UMR_S 1176, Paris-Sud University, Université Paris-Saclay, Le Kremlin-Bicêtre, France (F.A., A.K., M.B., D.B., O.D.C.)
| | - Alain Fischer
- INSERM, UMR_S 1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France (M.K., I.M., A.F., G.d.S.B., G.M.).,Imagine Institute (M.K., I.M., A.F., G.d.S.B., G.M.).,Department of Immunology and Pediatric Hematology (A.F.)
| | - Delphine Borgel
- From the INSERM, UMR_S 1176, Paris-Sud University, Université Paris-Saclay, Le Kremlin-Bicêtre, France (F.A., A.K., M.B., D.B., O.D.C.).,Biological Hematology Service (D.B.), Necker Children's Hospital, Assistance Publique-Hôpitaux de Paris, France; and Collège de France, Paris (A.F.)
| | - Geneviève de Saint Basile
- INSERM, UMR_S 1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France (M.K., I.M., A.F., G.d.S.B., G.M.).,Imagine Institute (M.K., I.M., A.F., G.d.S.B., G.M.)
| | - Olivier D Christophe
- From the INSERM, UMR_S 1176, Paris-Sud University, Université Paris-Saclay, Le Kremlin-Bicêtre, France (F.A., A.K., M.B., D.B., O.D.C.)
| | - Gaël Ménasché
- INSERM, UMR_S 1163, Laboratory of Normal and Pathological Homeostasis of the Immune System, Paris, France (M.K., I.M., A.F., G.d.S.B., G.M.).,Imagine Institute (M.K., I.M., A.F., G.d.S.B., G.M.)
| |
Collapse
|
14
|
Abstract
Platelet granules are unique among secretory vesicles in both their content and their life cycle. Platelets contain three major granule types—dense granules, α-granules, and lysosomes—although other granule types have been reported. Dense granules and α-granules are the most well-studied and the most physiologically important. Platelet granules are formed in large, multilobulated cells, termed megakaryocytes, prior to transport into platelets. The biogenesis of dense granules and α-granules involves common but also distinct pathways. Both are formed from the
trans-Golgi network and early endosomes and mature in multivesicular bodies, but the formation of dense granules requires trafficking machinery different from that of α-granules. Following formation in the megakaryocyte body, both granule types are transported through and mature in long proplatelet extensions prior to the release of nascent platelets into the bloodstream. Granules remain stored in circulating platelets until platelet activation triggers the exocytosis of their contents. Soluble
N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins, located on both the granules and target membranes, provide the mechanical energy that enables membrane fusion during both granulogenesis and exocytosis. The function of these core fusion engines is controlled by SNARE regulators, which direct the site, timing, and extent to which these SNAREs interact and consequently the resulting membrane fusion. In this review, we assess new developments in the study of platelet granules, from their generation to their exocytosis.
Collapse
Affiliation(s)
- Anish Sharda
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| | - Robert Flaumenhaft
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
| |
Collapse
|
15
|
Vogel GF, Janecke AR, Krainer IM, Gutleben K, Witting B, Mitton SG, Mansour S, Ballauff A, Roland JT, Engevik AC, Cutz E, Müller T, Goldenring JR, Huber LA, Hess MW. Abnormal Rab11-Rab8-vesicles cluster in enterocytes of patients with microvillus inclusion disease. Traffic 2017; 18:453-464. [PMID: 28407399 DOI: 10.1111/tra.12486] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 04/05/2017] [Accepted: 04/05/2017] [Indexed: 12/14/2022]
Abstract
Microvillus inclusion disease (MVID) is a congenital enteropathy characterized by accumulation of vesiculo-tubular endomembranes in the subapical cytoplasm of enterocytes, historically termed "secretory granules." However, neither their identity nor pathophysiological significance is well defined. Using immunoelectron microscopy and tomography, we studied biopsies from MVID patients (3× Myosin 5b mutations and 1× Syntaxin3 mutation) and compared them to controls and genome-edited CaCo2 cell models, harboring relevant mutations. Duodenal biopsies from 2 patients with novel Myosin 5b mutations and typical clinical symptoms showed unusual ultrastructural phenotypes: aberrant subapical vesicles and tubules were prominent in the enterocytes, though other histological hallmarks of MVID were almost absent (ectopic intra-/intercellular microvilli, brush border atrophy). We identified these enigmatic vesiculo-tubular organelles as Rab11-Rab8-positive recycling compartments of altered size, shape and location harboring the apical SNARE Syntaxin3, apical transporters sodium-hydrogen exchanger 3 (NHE3) and cystic fibrosis transmembrane conductance regulator. Our data strongly indicate that in MVID disrupted trafficking between cargo vesicles and the apical plasma membrane is the primary cause of a defect of epithelial polarity and subsequent facultative loss of brush border integrity, leading to malabsorption. Furthermore, they support the notion that mislocalization of transporters, such as NHE3 substantially contributes to the reported sodium loss diarrhea.
Collapse
Affiliation(s)
- Georg F Vogel
- Division of Histology and Embryology, Medical University of Innsbruck, Innsbruck, Austria.,Division of Cell Biology, Medical University of Innsbruck, Innsbruck, Austria.,Department of Paediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Andreas R Janecke
- Department of Paediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Iris M Krainer
- Division of Cell Biology, Medical University of Innsbruck, Innsbruck, Austria.,Department of Paediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Karin Gutleben
- Division of Histology and Embryology, Medical University of Innsbruck, Innsbruck, Austria
| | - Barbara Witting
- Division of Histology and Embryology, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Sahar Mansour
- Human Genetics Research Center, St. George's University of London, London, UK
| | | | - Joseph T Roland
- Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee.,Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.,Departments of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Amy C Engevik
- Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee.,Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.,Departments of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Ernest Cutz
- Division of Pathology, Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Thomas Müller
- Department of Paediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - James R Goldenring
- Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee.,Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, Tennessee.,Departments of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Lukas A Huber
- Division of Cell Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael W Hess
- Division of Histology and Embryology, Medical University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
16
|
Lopez JJ, Salido GM, Rosado JA. Cardiovascular and Hemostatic Disorders: SOCE and Ca 2+ Handling in Platelet Dysfunction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:453-472. [PMID: 28900928 DOI: 10.1007/978-3-319-57732-6_23] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Among the Ca2+ entry mechanisms in platelets, store-operated Ca2+ entry (SOCE) plays a prominent role as it is necessary to achieve full activation of platelet functions and replenish intracellular Ca2+ stores. In platelets, as in other non-excitable cells, SOCE has been reported to involve the activation of plasma membrane channels by the ER Ca2+ sensor STIM1. Despite electrophysiological studies are not possible in human platelets, indirect analyses have revealed that the Ca2+-permeable channels involve Orai1 and, most likely, TRPC1 subunits. A relevant role for the latter has not been found in mouse platelets. There is a body of evidence revealing a number of abnormalities in SOCE or in its molecular regulators that result in qualitative platelet disorders and, as a consequence, altered platelet responsiveness upon stimulation with multiple physiological agonists. Platelet SOCE abnormalities include STIM1 and Orai1 mutations. This chapter summarizes the current knowledge in this field, as well as the disorders associated to platelet SOCE dysfunction.
Collapse
Affiliation(s)
- Jose J Lopez
- Cell Physiology Research Group, Department of Physiology, University of Extremadura, Cáceres, Spain
| | - Gines M Salido
- Cell Physiology Research Group, Department of Physiology, University of Extremadura, Cáceres, Spain
| | - Juan A Rosado
- Cell Physiology Research Group, Department of Physiology, University of Extremadura, Cáceres, Spain.
| |
Collapse
|
17
|
Abstract
Secretion is essential to many of the roles that platelets play in the vasculature, e.g., thrombosis, angiogenesis, and inflammation, enabling platelets to modulate the microenvironment at sites of vascular lesions with a myriad of bioactive molecules stored in their granules. Past studies demonstrate that granule cargo release is mediated by Soluble NSF Attachment Protein Receptor (SNARE) proteins, which are required for granule-plasma membrane fusion. Several SNARE regulators, which control when, where, and how the SNAREs interact, have been identified in platelets. Additionally, platelet SNAREs are controlled by post-translational modifications, e.g., phosphorylation and acylation. Although there have been many recent insights into the mechanisms of platelet secretion, many questions remain: have we identified all the important regulators, does calcium directly control the process, and is platelet secretion polarized. In this review, we focus on the mechanics of platelet secretion and discuss how the secretory machinery functions in the pathway leading to membrane fusion and cargo release.
Collapse
Affiliation(s)
- Smita Joshi
- a Department of Molecular and Cellular Biochemistry , University of Kentucky , Lexington , KY , USA
| | - Sidney W Whiteheart
- a Department of Molecular and Cellular Biochemistry , University of Kentucky , Lexington , KY , USA
| |
Collapse
|
18
|
Lycopene acts through inhibition of IκB kinase to suppress NF-κB signaling in human prostate and breast cancer cells. Tumour Biol 2016; 37:9375-85. [PMID: 26779636 DOI: 10.1007/s13277-016-4798-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 01/06/2016] [Indexed: 01/03/2023] Open
Abstract
We studied the effect of the potent dietary antioxidant lycopene on multiple points along the nuclear factor kappa B (NF-κB) signaling pathway in prostate and breast cancer cells. Lycopene significantly inhibited prostate and breast cancer cell growth at physiologically relevant concentrations of ≥1.25 μM. Similar concentrations also caused a 30-40 % reduction in inhibitor of kappa B (IκB) phosphorylation in the cells, as determined by western blotting. Furthermore, the same degree of inhibition by lycopene was observed for NF-κB transcriptional activity, as determined by reporter gene assay. Concomitant with this, immunofluorescence staining of lycopene-treated cells showed a significant suppression (≥25 %) of TNF-induced NF-κB p65 subunit nuclear translocation. Further probing of lycopene's effects on upstream elements of the NF-κB pathway showed a 25 % inhibition of both activity of recombinant IκB kinase β (IKKβ) kinase in a cell-free in vitro assay, as well as activity of IKKβ immunoprecipitated from MDA-MB-231 cells treated with lycopene. In conclusion, the anticancer properties of lycopene may occur through inhibition of the NF-κB signaling pathway, beginning at the early stage of cytoplasmic IKK kinase activity, which then leads to reduced NF-κB-responsive gene regulation. Furthermore, these effects in cancer cells were observed at concentrations of lycopene that are relevant and achievable in vivo.
Collapse
|
19
|
Role of Munc13-4 as a Ca2+-dependent tether during platelet secretion. Biochem J 2015; 473:627-39. [PMID: 26637270 DOI: 10.1042/bj20151150] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 12/04/2015] [Indexed: 11/17/2022]
Abstract
The Munc13 family of exocytosis regulators has multiple Ca(2+)-binding, C2 domains. Here, we probed the mechanism by which Munc13-4 regulates in vitro membrane fusion and platelet exocytosis. We show that Munc13-4 enhances in vitro soluble NSF attachment protein receptor (SNARE)-dependent, proteoliposome fusion in a Ca(2+)- and phosphatidylserine (PS)-dependent manner that was independent of SNARE concentrations. Munc13-4-SNARE interactions, under the conditions used, were minimal in the absence or presence of Ca(2+). However, Munc13-4 was able to bind and cluster liposomes harbouring PS in response to Ca(2+). Interestingly, Ca(2+)-dependent liposome binding/clustering and enhancement of proteoliposome fusion required both Munc13-4 C2 domains, but only the Ca(2+)-liganding aspartate residues of the C2B domain. Analytical ultracentrifugation (AUC) measurements indicated that, in solution, Munc13-4 was a monomeric prolate ellipsoid with dimensions consistent with a molecule that could bridge two fusing membranes. To address the potential role of Munc13-4 as a tethering protein in platelets, we examined mepacrine-stained, dense granule mobility and secretion in platelets from wild-type and Munc13-4 null (Unc13d(Jinx)) mice. In the absence of Munc13-4, dense granules were highly mobile in both resting and stimulated platelets, and stimulation-dependent granule release was absent. These observations suggest that dense granules are stably docked in resting platelets awaiting stimulation and that Munc13-4 plays a vesicle-stabilizing or tethering role in resting platelets and also in activated platelets in response to Ca(2+). In summary, we show that Munc13-4 conveys Ca(2+) sensitivity to platelet SNARE-mediated membrane fusion and reveal a potential mechanism by which Munc13-4 bridges and stabilizes apposing membranes destined for fusion.
Collapse
|
20
|
Heijnen H, van der Sluijs P. Platelet secretory behaviour: as diverse as the granules … or not? J Thromb Haemost 2015; 13:2141-51. [PMID: 26391322 DOI: 10.1111/jth.13147] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 09/05/2015] [Indexed: 12/19/2022]
Abstract
Platelets play a central role in the arrest of bleeding after damage to a blood vessel and in the development of thrombosis. Platelets rapidly respond after interaction with sub-endothelial components and release cargo from their storage granules. The three principal granule types of platelets are α-granules, dense granules and lysosomes. Timed release of granule contents and regulated expression of critical receptors are essential for maintenance of the platelet thrombus, yet also have important functions beyond hemostasis (i.e. inflammatory reactions and immune responses). α-granules store adhesive molecules such as von Willebrand factor and fibrinogen, growth factors and inflammatory and angiogenic mediators, which play crucial roles in inflammatory responses and tumor genesis. The α-granules comprise a group of subcellular compartments with a unique composition and ultrastructure. Recent studies have suggested that differential secretory kinetics of α-granule subtypes is responsible for a thematic release of adhesive and inflammatory mediators. In addition, new results indicate that activation-dependent synthesis and release of cytokines also contribute to the inflammatory role of platelets. We will discuss the various methods that platelets use to regulate secretory processes and how these relate to potential differential secretion patterns, thereby promoting adhesiveness and/or inflammatory functions. We will focus on the heterogenic granule population, open canalicular system (OCS) plasticity, the role of contractile and mechanobiological forces, and the fusogenic machinery.
Collapse
Affiliation(s)
- H Heijnen
- Department of Clinical Chemistry and Hematology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - P van der Sluijs
- Department of Cell Biology, University Medical Center Utrecht, Utrecht, the Netherlands
| |
Collapse
|
21
|
Xu X, Sun B. Platelet granule secretion mechanisms: Are they modified in sepsis? Thromb Res 2015; 136:845-50. [DOI: 10.1016/j.thromres.2015.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/19/2015] [Accepted: 09/06/2015] [Indexed: 12/31/2022]
|
22
|
Lopez E, Bermejo N, Berna-Erro A, Alonso N, Salido GM, Redondo PC, Rosado JA. Relationship between calcium mobilization and platelet α- and δ-granule secretion. A role for TRPC6 in thrombin-evoked δ-granule exocytosis. Arch Biochem Biophys 2015; 585:75-81. [PMID: 26386308 DOI: 10.1016/j.abb.2015.09.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 11/25/2022]
Abstract
Changes in cytosolic Ca(2+) concentration ([Ca(2+)]c) regulate granule secretion in different cell types. Thrombin activates PAR1 and PAR4 receptors and promotes release of Ca(2+) from distinct intracellular stores, which, in turn, activates store-operated Ca(2+) entry (SOCE). A crucial step during platelet function is the release of physiological agonists stored in secretory granules to the extracellular compartment during activation. We aim to study the role of Ca(2+) mobilization from the extracellular compartment or from different intracellular stores in platelet granule secretion. By using flow cytometry, we have found that α- and δ-granules are secreted in thrombin-stimulated platelets in the absence of extracellular Ca(2+), and in a concentration-dependent manner. Our findings show that thrombin-stimulated granule secretion depends on Ca(2+) mobilization from intracellular stores. Analysis of the kinetics of granule secretion reveals that platelet stimulation with thrombin results in rapid release of α-granules which precedes the secretion of δ-granules. Incubation of platelets with a specific antibody, which recognizes the extracellular amino acid sequence 573-586 of TRPC6, inhibited thrombin-evoked δ-granule exocytosis. Our results indicate that the mechanisms underlying thrombin-induced α- and δ-granule secretion show differences in dependency on Ca(2+) mobilization.
Collapse
Affiliation(s)
- E Lopez
- Department of Physiology, University of Extremadura, Phycell, 10003, Spain
| | - N Bermejo
- Department of Hematology, Hospital San Pedro de Alcantara, 10003 Cáceres, Spain
| | - A Berna-Erro
- Department of Physiology, University of Extremadura, Phycell, 10003, Spain
| | - N Alonso
- Department of Hematology, Hospital Infanta Cristina, 06006 Badajoz, Spain
| | - G M Salido
- Department of Physiology, University of Extremadura, Phycell, 10003, Spain
| | - P C Redondo
- Department of Physiology, University of Extremadura, Phycell, 10003, Spain
| | - J A Rosado
- Department of Physiology, University of Extremadura, Phycell, 10003, Spain.
| |
Collapse
|
23
|
Walker B, Schmid E, Russo A, Schmidt EM, Burk O, Münzer P, Velic A, Macek B, Schaller M, Schwab M, Seabra MC, Gawaz M, Lang F, Borst O. Impact of the serum- and glucocorticoid-inducible kinase 1 on platelet dense granule biogenesis and secretion. J Thromb Haemost 2015; 13:1325-34. [PMID: 25944668 DOI: 10.1111/jth.12998] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Indexed: 02/04/2023]
Abstract
BACKGROUND Platelet secretion is critical to development of acute thrombotic occlusion. Platelet dense granules contain a variety of important hemostatically active substances. Nevertheless, biogenesis of platelet granules is poorly understood. OBJECTIVES Serum- and glucocorticoid-inducible kinase 1 (SGK1) has been shown to be highly expressed in platelets and megakaryocytes, but its role in the regulation of platelet granule biogenesis and its impact on thrombosis has not been investigated so far. METHODS AND RESULTS Electron microscopy analysis of the platelet ultrastructure revealed a significant reduction in the number and packing of dense granules in platelets lacking SGK1 (sgk1(-/-) ). In sgk1(-/-) platelets serotonin content was significantly reduced and activation-dependent secretion of ATP, serotonin and CD63 significantly impaired. In vivo adhesion after carotis ligation was significantly decreased in platelets lacking SGK1 and occlusive thrombus formation after FeCl3 -induced vascular injury was significantly diminished in sgk1(-/-) mice. Transcript levels and protein abundance of dense granule biogenesis regulating GTPase Rab27b were significantly reduced in sgk1(-/-) platelets without affecting Rab27b mRNA stability. In MEG-01 cells transfection with constitutively active (S422) (D) SGK1 but not with inactive (K127) (N) SGK1 significantly enhanced Rab27b mRNA levels. Sgk1(-/-) megakaryocytes show significantly reduced expression of Rab27b and serotonin/CD63 levels compared with sgk1(+/+) megakaryocytes. Proteome analysis identified nine further vesicular transport proteins regulated by SGK1, which may have an impact on impaired platelet granule biogenesis in sgk1(-/-) platelets independent of Rab27b. CONCLUSIONS The present observations identify SGK1 as a novel powerful regulator of platelet dense granule biogenesis, platelet secretion and thrombus formation. SGK1 is at least partially effective because it regulates transcription of Rab27b in megakaryocytes.
Collapse
Affiliation(s)
- B Walker
- Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - E Schmid
- Department of Pediatric Surgery and Pediatric Urology, University Children's Hospital Tübingen, Tübingen, Germany
| | - A Russo
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - E-M Schmidt
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - O Burk
- Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
| | - P Münzer
- Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - A Velic
- Proteom Center Tübingen, University of Tübingen, Tübingen, Germany
| | - B Macek
- Proteom Center Tübingen, University of Tübingen, Tübingen, Germany
| | - M Schaller
- Department of Dermatology, University Hospital Tübingen, Tübingen, Germany
| | - M Schwab
- Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
- Department of Clinical Pharmacology, University Hospital, Tübingen, Germany
| | - M C Seabra
- Molecular Medicine, National Heart and Lung Institute, Imperial College London, London, UK
| | - M Gawaz
- Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany
| | - F Lang
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - O Borst
- Department of Cardiology and Cardiovascular Medicine, University of Tübingen, Tübingen, Germany
- Department of Physiology, University of Tübingen, Tübingen, Germany
| |
Collapse
|
24
|
VAMP-7 links granule exocytosis to actin reorganization during platelet activation. Blood 2015; 126:651-60. [PMID: 25999457 DOI: 10.1182/blood-2014-12-618744] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 05/09/2015] [Indexed: 01/30/2023] Open
Abstract
Platelet activation results in profound morphologic changes accompanied by release of granule contents. Recent evidence indicates that fusion of granules with the plasma membrane during activation provides auxiliary membrane to cover growing actin structures. Yet little is known about how membrane fusion is coupled with actin reorganization. Vesicle-associated membrane protein (VAMP)-7 is found on platelet vesicles and possesses an N-terminal longin domain capable of linking exocytosis to cytoskeletal remodeling. We have evaluated platelets from VAMP-7(-/-) mice to determine whether this VAMP isoform contributes to granule release and platelet spreading. VAMP-7(-/-) platelets demonstrated a partial defect in dense granule exocytosis and impaired aggregation. α Granule exocytosis from VAMP-7(-/-) platelets was diminished both in vitro and in vivo during thrombus formation. Consistent with a role of VAMP-7 in cytoskeletal remodeling, spreading on matrices was decreased in VAMP-7(-/-) platelets compared to wild-type controls. Immunoprecipitation of VAMP-7 revealed an association with VPS9-domain ankyrin repeat protein (VARP), an adaptor protein that interacts with both membrane-bound and cytoskeleton proteins and with Arp2/3. VAMP-7, VARP, and Arp2/3 localized to the platelet periphery during spreading. These studies demonstrate that VAMP-7 participates in both platelet granule secretion and spreading and suggest a mechanism whereby VAMP-7 links granule exocytosis with actin reorganization.
Collapse
|
25
|
Ye S, Huang Y, Joshi S, Zhang J, Yang F, Zhang G, Smyth SS, Li Z, Takai Y, Whiteheart SW. Platelet secretion and hemostasis require syntaxin-binding protein STXBP5. J Clin Invest 2014; 124:4517-28. [PMID: 25244094 DOI: 10.1172/jci75572] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 07/24/2014] [Indexed: 01/22/2023] Open
Abstract
Genome-wide association studies (GWAS) have linked genes encoding several soluble NSF attachment protein receptor (SNARE) regulators to cardiovascular disease risk factors. Because these regulatory proteins may directly affect platelet secretion, we used SNARE-containing complexes to affinity purify potential regulators from human platelet extracts. Syntaxin-binding protein 5 (STXBP5; also known as tomosyn-1) was identified by mass spectrometry, and its expression in isolated platelets was confirmed by RT-PCR analysis. Coimmunoprecipitation studies showed that STXBP5 interacts with core secretion machinery complexes, such as syntaxin-11/SNAP23 heterodimers, and fractionation studies suggested that STXBP5 also interacts with the platelet cytoskeleton. Platelets from Stxbp5 KO mice had normal expression of other key secretory components; however, stimulation-dependent secretion from each of the 3 granule types was markedly defective. Secretion defects in STXBP5-deficient platelets were confirmed via lumi-aggregometry and FACS analysis for P-selectin and LAMP-1 exposure. Interestingly, STXBP5-deficient platelets had altered granule cargo levels, despite having normal morphology and granule numbers. Consistent with secretion and cargo deficiencies, Stxbp5 KO mice showed dramatic bleeding in the tail transection model and defective hemostasis in the FeCl3-induced carotid injury model. Transplantation experiments indicated that these defects were due to loss of STXBP5 in BM-derived cells. Our data demonstrate that STXBP5 is required for normal arterial hemostasis, due to its contributions to platelet granule cargo packaging and secretion.
Collapse
|
26
|
STXBP1 promotes Weibel-Palade body exocytosis through its interaction with the Rab27A effector Slp4-a. Blood 2014; 123:3185-94. [PMID: 24700782 DOI: 10.1182/blood-2013-10-535831] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Vascular endothelial cells contain unique rod-shaped secretory organelles, called Weibel-Palade bodies (WPBs), which contain the hemostatic protein von Willebrand factor (VWF) and a cocktail of angiogenic and inflammatory mediators. We have shown that the Rab27A effector synaptotagmin-like protein 4-a (Slp4-a) plays a critical role in regulating hormone-evoked WPB exocytosis. Using a nonbiased proteomic screen for targets for Slp4-a, we now identify syntaxin-binding protein 1 (STXBP1) and syntaxin-2 and -3 as endogenous Slp4-a binding partners in endothelial cells. Coimmunoprecipitations showed that STXBP1 interacts with syntaxin-2 and -3, but not with syntaxin-4. Small interfering RNA-mediated silencing of STXBP1 expression impaired histamine- and forskolin-induced VWF secretion. To further substantiate the role of STXBP1, we isolated blood outgrowth endothelial cells (BOECs) from an early infantile epileptic encephalopathy type 4 (EIEE4) patient carrying a de novo mutation in STXBP1. STXBP1-haploinsufficient EIEE4 BOECs contained similar numbers of morphologically normal WPBs compared with control BOECs of healthy donors; however, EIEE4 BOECs displayed significantly impaired histamine- and forskolin-stimulated VWF secretion. Based on these findings, we propose that the Rab27A-Slp4-a complex on WPB promotes exocytosis through an interaction with STXBP1, thereby controlling the release of vaso-active substances in the vasculature.
Collapse
|
27
|
Sun Y, Chiu TT, Foley KP, Bilan PJ, Klip A. Myosin Va mediates Rab8A-regulated GLUT4 vesicle exocytosis in insulin-stimulated muscle cells. Mol Biol Cell 2014; 25:1159-70. [PMID: 24478457 PMCID: PMC3967978 DOI: 10.1091/mbc.e13-08-0493] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Rab-GTPases are important molecular switches regulating intracellular vesicle traffic, and we recently showed that Rab8A and Rab13 are activated by insulin in muscle to mobilize GLUT4-containing vesicles to the muscle cell surface. Here we show that the unconventional motor protein myosin Va (MyoVa) is an effector of Rab8A in this process. In CHO-IR cell lysates, a glutathione S-transferase chimera of the cargo-binding COOH tail (CT) of MyoVa binds Rab8A and the related Rab10, but not Rab13. Binding to Rab8A is stimulated by insulin in a phosphatidylinositol 3-kinase-dependent manner, whereas Rab10 binding is insulin insensitive. MyoVa-CT preferentially binds GTP-locked Rab8A. Full-length green fluorescent protein (GFP)-MyoVa colocalizes with mCherry-Rab8A in perinuclear small puncta, whereas GFP-MyoVa-CT collapses the GTPase into enlarged perinuclear depots. Further, GFP-MyoVa-CT blocks insulin-stimulated translocation of exofacially myc-tagged GLUT4 to the surface of muscle cells. Mutation of amino acids in MyoVa-CT predicted to bind Rab8A abrogates both interaction with Rab8A (not Rab10) and inhibition of insulin-stimulated GLUT4myc translocation. Of importance, small interfering RNA-mediated MyoVa silencing reduces insulin-stimulated GLUT4myc translocation. Rab8A colocalizes with GLUT4 in perinuclear but not submembrane regions visualized by confocal total internal reflection fluorescence microscopy. Hence insulin signaling to the molecular switch Rab8A connects with the motor protein MyoVa to mobilize GLUT4 vesicles toward the muscle cell plasma membrane.
Collapse
Affiliation(s)
- Yi Sun
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | | | | | | | | |
Collapse
|
28
|
Golebiewska EM, Poole AW. Secrets of platelet exocytosis - what do we really know about platelet secretion mechanisms? Br J Haematol 2013; 165:204-216. [PMID: 24588354 PMCID: PMC4155865 DOI: 10.1111/bjh.12682] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Upon activation by extracellular matrix components or soluble agonists, platelets release in excess of 300 active molecules from intracellular granules. Those factors can both activate further platelets and mediate a range of responses in other cells. The complex microenvironment of a growing thrombus, as well as platelets' roles in both physiological and pathological processes, require platelet secretion to be highly spatially and temporally regulated to ensure appropriate responses to a range of stimuli. However, how this regulation is achieved remains incompletely understood. In this review we outline the importance of regulated secretion in thrombosis as well as in 'novel' scenarios beyond haemostasis and give a detailed summary of what is known about the molecular mechanisms of platelet exocytosis. We also discuss a number of theories of how different cargoes could be released in a tightly orchestrated manner, allowing complex interactions between platelets and their environment.
Collapse
Affiliation(s)
- Ewelina M Golebiewska
- School of Physiology and Pharmacology, Bristol Heart Institute, University of Bristol, Bristol, UK
| | | |
Collapse
|
29
|
Abstract
PURPOSE OF REVIEW This review will provide an overview of several recent advances in the field of platelet granule biology. RECENT FINDINGS The past few years have witnessed a substantial evolution in our knowledge of platelet granules based on a number of discoveries and new experimental approaches. This article will cover recent studies in five areas. First, the vesicle trafficking pathways responsible for α-granule formation are beginning to be assembled as a result of the characterization of patients with α-granule deficiencies. Second, a revision of our understanding of which SNARE isoforms mediate platelet granule exocytosis has occurred following evaluation of patients with defects in platelet granule exocytosis and the generation of mice lacking specific SNAREs. Third, investigators have begun to establish how cargos are segregated among α-granules and determine whether or not different α-granule subpopulations exist in platelets. Fourth, an unanticipated role for α-granules in platelet spreading has been identified. Fifth, single-cell amperometry has revealed secretion kinetics with submillisecond temporal resolution enabling evaluation of the molecular control of the platelet fusion pore. SUMMARY These new observations reveal a previously unappreciated complexity to platelet granule formation and exocytosis and challenge our earlier notions of how these granules are organized within platelets and contribute to the multitude of physiological activities in which platelets function.
Collapse
Affiliation(s)
- Secil Koseoglu
- Division of Hemostasis and Thrombosis, Department of Medicine, BIDMC, Harvard Medical School, Boston, Massachusetts 02215, USA
| | | |
Collapse
|
30
|
Fukuda M. Rab27 effectors, pleiotropic regulators in secretory pathways. Traffic 2013; 14:949-63. [PMID: 23678941 DOI: 10.1111/tra.12083] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 05/13/2013] [Accepted: 05/16/2013] [Indexed: 12/18/2022]
Abstract
Rab27, a member of the small GTPase Rab family, is widely conserved in metazoan, and two Rab27 isoforms, Rab27A and Rab27B, are present in vertebrates. Rab27A was the first Rab protein whose dysfunction was found to cause a human hereditary disease, type 2 Griscelli syndrome, which is characterized by silvery hair and immunodeficiency. The discovery in the 21st century of three distinct types of mammalian Rab27A effectors [synaptotagmin-like protein (Slp), Slp homologue lacking C2 domains (Slac2), and Munc13-4] that specifically bind active Rab27A has greatly accelerated our understanding not only of the molecular mechanisms of Rab27A-mediated membrane traffic (e.g. melanosome transport and regulated secretion) but of the symptoms of Griscelli syndrome patients at the molecular level. Because Rab27B is widely expressed in various tissues together with Rab27A and has been found to have the ability to bind all of the Rab27A effectors that have been tested, Rab27A and Rab27B were initially thought to function redundantly by sharing common Rab27 effectors. However, recent evidence has indicated that by interacting with different Rab27 effectors Rab27A and Rab27B play different roles in special types of secretion (e.g. exosome secretion and mast cell secretion) even within the same cell type. In this review article, I describe the current state of our understanding of the functions of Rab27 effectors in secretory pathways.
Collapse
Affiliation(s)
- Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
| |
Collapse
|