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Takabayashi T, Kato A, Peters AT, Hulse KE, Suh LA, Carter R, Norton J, Grammer LC, Tan BK, Chandra RK, Conley DB, Kern RC, Fujieda S, Schleimer RP. Increased expression of factor XIII-A in patients with chronic rhinosinusitis with nasal polyps. J Allergy Clin Immunol 2013; 132:584-592.e4. [PMID: 23541322 DOI: 10.1016/j.jaci.2013.02.003] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 01/31/2013] [Accepted: 02/07/2013] [Indexed: 01/09/2023]
Abstract
BACKGROUND Profound edema or formation of a pseudocyst containing plasma proteins is a prominent characteristic of nasal polyps (NP). However, the mechanisms underlying NP retention of plasma proteins in the submucosa remain unclear. Recently, we reported that impairment of fibrinolysis causes excessive fibrin deposition in NP and this might be involved in the retention of plasma proteins. Although the coagulation cascade plays a critical role in fibrin clot formation at extravascular sites, the expression and role of coagulation factors in NP remain unclear. OBJECTIVE The objective of this study was to investigate the expression of coagulation factors in patients with chronic rhinosinusitis (CRS). METHODS Sinonasal tissues were collected from patients with CRS and control subjects. We assayed mRNA for factor XIII-A (FXIII-A) by using real-time PCR and measured FXIII-A protein by means of ELISA, immunohistochemistry, and immunofluorescence. RESULTS FXIII-A mRNA levels were significantly increased in NP tissue from patients with CRS with NP (P < .001) compared with uncinate tissue from patients with CRS or control subjects. Similarly, FXIII-A protein levels were increased in NP. Immunofluorescence analysis revealed that FXIII-A expression in inflammatory cells and FXIII-A(+) cell numbers were significantly increased in NP. Most FXIII-A staining was observed within CD68(+)/CD163(+) M2 macrophages in NP. Levels of FXIII-A correlated with markers of M2 macrophages, suggesting that M2 macrophages are major FXIIIA-producing cells in NP. CONCLUSION Overproduction of FXIII-A by M2 macrophages might contribute to the excessive fibrin deposition in the submucosa of NP, which might contribute to the tissue remodeling and pathogenesis of CRS with NP.
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Affiliation(s)
- Tetsuji Takabayashi
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill; Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, University of Fukui, Fukui, Japan
| | - Atsushi Kato
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Anju T Peters
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Kathryn E Hulse
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Lydia A Suh
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Roderick Carter
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - James Norton
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Leslie C Grammer
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Bruce K Tan
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Rakesh K Chandra
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - David B Conley
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Robert C Kern
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Shigeharu Fujieda
- Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, University of Fukui, Fukui, Japan
| | - Robert P Schleimer
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill; Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
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Abbonante V, Gruppi C, Rubel D, Gross O, Moratti R, Balduini A. Discoidin domain receptor 1 protein is a novel modulator of megakaryocyte-collagen interactions. J Biol Chem 2013; 288:16738-16746. [PMID: 23530036 DOI: 10.1074/jbc.m112.431528] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Growing evidence demonstrates that extracellular matrices regulate many aspects of megakaryocyte (MK) development; however, among the different extracellular matrix receptors, integrin α2β1 and glycoprotein VI are the only collagen receptors studied in platelets and MKs. In this study, we demonstrate the expression of the novel collagen receptor discoidin domain receptor 1 (DDR1) by human MKs at both mRNA and protein levels and provide evidence of DDR1 involvement in the regulation of MK motility on type I collagen through a mechanism based on the activity of SHP1 phosphatase and spleen tyrosine kinase (Syk). Specifically, we demonstrated that inhibition of DDR1 binding to type I collagen, preserving the engagement of the other collagen receptors, glycoprotein VI, α2β1, and LAIR-1, determines a decrease in MK migration due to the reduction in SHP1 phosphatase activity and consequent increase in the phosphorylation level of its main substrate Syk. Consistently, inhibition of Syk activity restored MK migration on type I collagen. In conclusion, we report the expression and function of a novel collagen receptor on human MKs, and we point out that an increasing level of complexity is necessary to better understand MK-collagen interactions in the bone marrow environment.
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Affiliation(s)
- Vittorio Abbonante
- Biotechnology Research Laboratories, Department of Molecular Medicine, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) San Matteo Foundation, University of Pavia, 27100 Pavia, Italy
| | - Cristian Gruppi
- Biotechnology Research Laboratories, Department of Molecular Medicine, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) San Matteo Foundation, University of Pavia, 27100 Pavia, Italy
| | - Diana Rubel
- Department of Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
| | - Oliver Gross
- Department of Nephrology and Rheumatology, University Medical Center Goettingen, 37075 Goettingen, Germany
| | - Remigio Moratti
- Biotechnology Research Laboratories, Department of Molecular Medicine, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) San Matteo Foundation, University of Pavia, 27100 Pavia, Italy
| | - Alessandra Balduini
- Biotechnology Research Laboratories, Department of Molecular Medicine, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) San Matteo Foundation, University of Pavia, 27100 Pavia, Italy; Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155.
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High doses of romiplostim induce proliferation and reduce proplatelet formation by human megakaryocytes. PLoS One 2013; 8:e54723. [PMID: 23359807 PMCID: PMC3554640 DOI: 10.1371/journal.pone.0054723] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Accepted: 12/17/2012] [Indexed: 12/21/2022] Open
Abstract
Background Romiplostim (AMG531) is a Thrombopoietin (TPO) receptor agonist with no homology with the endogenous TPO that has been used to treat patients affected by immune thrombocytopenia (ITP). Despite the use of TPO mimetics in the clinical practice, the mechanisms underlying their impact on megakaryocyte function is still unknown. Methodology/Principal Findings In this project we took advantage of an in vitro human model, that we have established in our laboratory for long time to study megakaryocyte development from human cord blood-derived progenitor cells, and we demonstrated that increasing doses of AMG531 (100 to 2000 ng/mL) determine a progressive increase of megakaryocyte proliferation with a parallel decrease in megakaryocyte ploidy and capacity of extending proplatelets. Most importantly, these differences in megakaryocyte function seemed to be correlated to modulation of AKT phosphorylation. Conclusions/Significance Overall our results shed new light on the mechanisms and on the relevance of dosage related to AMG531 impact on megakaryocyte function.
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Lambert MP, Sullivan S, Poncz M. Making Platelets Ex Vivo. Platelets 2013. [DOI: 10.1016/b978-0-12-387837-3.00063-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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55
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Induction of megakaryocyte differentiation drives nuclear accumulation and transcriptional function of MKL1 via actin polymerization and RhoA activation. Blood 2012; 121:1094-101. [PMID: 23243284 DOI: 10.1182/blood-2012-05-429993] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
How components of the cytoskeleton regulate complex cellular responses is fundamental to understanding cellular function. Megakaryoblast leukemia 1 (MKL1), an activator of serum response factor (SRF) transcriptional activity, promotes muscle, neuron, and megakaryocyte differentiation. In muscle cells, where MKL1 subcellular localization is one mechanism by which cells control SRF activity, MKL1 translocation from the cytoplasm to the nucleus in response to actin polymerization is critical for its function as a transcriptional regulator. MKL1 localization is cell-type specific; it is predominantly cytoplasmic in unstimulated fibroblasts and some muscle cell types and is constitutively nuclear in neuronal cells. In the present study, we report that in megakaryocytes, subcellular localization and regulation of MKL1 is dependent on RhoA activity and actin organization. Induction of megakaryocytic differentiation of human erythroleukemia cells by 12-O-tetradecanoylphorbol-13-acetate and primary megakaryocytes by thrombopoietin promotes MKL1 nuclear localization. This MKL1 localization is blocked by drugs inhibiting RhoA activity or actin polymerization.We also show that nuclear-localized MKL1 activates the transcription of SRF target genes. This report broadens our knowledge of the molecular mechanisms regulating megakaryocyte differentiation.
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Abstract
FXIII (Factor XIII) is a Ca2+-dependent enzyme which forms covalent ϵ-(γ-glutamyl)lysine cross-links between the γ-carboxy-amine group of a glutamine residue and the ϵ-amino group of a lysine residue. FXIII was originally identified as a protein involved in fibrin clot stabilization; however, additional extracellular and intracellular roles for FXIII have been identified which influence thrombus resolution and tissue repair. The present review discusses the substrates of FXIIIa (activated FXIII) involved in thrombosis and wound healing with a particular focus on: (i) the influence of plasma FXIIIa on the formation of stable fibrin clots able to withstand mechanical and enzymatic breakdown through fibrin–fibrin cross-linking and cross-linking of fibrinolysis inhibitors, in particular α2-antiplasmin; (ii) the role of intracellular FXIIIa in clot retraction through cross-linking of platelet cytoskeleton proteins, including actin, myosin, filamin and vinculin; (iii) the role of intracellular FXIIIa in cross-linking the cytoplasmic tails of monocyte AT1Rs (angiotensin type 1 receptors) and potential effects on the development of atherosclerosis; and (iv) the role of FXIIIa on matrix deposition and tissue repair, including cross-linking of extracellular matrix proteins, such as fibronectin, collagen and von Willebrand factor, and the effects on matrix deposition and cell–matrix interactions. The review highlights the central role of FXIIIa in the regulation of thrombus stability, thrombus regulation, cell–matrix interactions and wound healing, which is supported by observations in FXIII-deficient humans and animals.
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Balduini A, Di Buduo CA, Malara A, Lecchi A, Rebuzzini P, Currao M, Pallotta I, Jakubowski JA, Cattaneo M. Constitutively released adenosine diphosphate regulates proplatelet formation by human megakaryocytes. Haematologica 2012; 97:1657-65. [PMID: 22689668 DOI: 10.3324/haematol.2011.059212] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND The interaction of adenosine diphosphate with its P2Y(1) and P2Y(12) receptors on platelets is important for platelet function. However, nothing is known about adenosine diphosphate and its function in human megakaryocytes. DESIGN AND METHODS We studied the role of adenosine diphosphate and P2Y receptors on proplatelet formation by human megakaryocytes in culture. RESULTS Megakaryocytes expressed all the known eight subtypes of P2Y receptors, and constitutively released adenosine diphosphate. Proplatelet formation was inhibited by the adenosine diphosphate scavengers apyrase and CP/CPK by 60-70% and by the P2Y(12) inhibitors cangrelor and 2-MeSAMP by 50-60%, but was not inhibited by the P2Y(1) inhibitor MRS 2179. However, the active metabolites of the anti-P2Y(12) drugs, clopidogrel and prasugrel, did not inhibit proplatelet formation. Since cangrelor and 2-MeSAMP also interact with P2Y(13), we hypothesized that P2Y(13), rather than P2Y(12) is involved in adenosine diphosphate-regulated proplatelet formation. The specific P2Y(13) inhibitor MRS 2211 inhibited proplatelet formation in a concentration-dependent manner. Megakaryocytes from a patient with severe congenital P2Y(12) deficiency showed normal proplatelet formation, which was inhibited by apyrase, cangrelor or MRS 2211 by 50-60%. The platelet count of patients with congenital delta-storage pool deficiency, who lack secretable adenosine diphosphate, was significantly lower than that of patients with other platelet function disorders, confirming the important role of secretable adenosine diphosphate in platelet formation. CONCLUSIONS This is the first demonstration that adenosine diphosphate released by megakaryocytes regulates their function by interacting with P2Y(13). The clinical relevance of this not previously described physiological role of adenosine diphosphate and P2Y(13) requires further exploration.
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Affiliation(s)
- Alessandra Balduini
- Biotechnology Laboratories, Department of Molecular Medicine, IRCCS San Matteo Foundation, Università degli Studi di Pavia, Pavia, Italy
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Merico V, Zuccotti M, Carpi D, Baev D, Mulas F, Sacchi L, Bellazzi R, Pastorelli R, Redi CA, Moratti R, Garagna S, Balduini A. The genomic and proteomic blueprint of mouse megakaryocytes derived from embryonic stem cells. J Thromb Haemost 2012; 10:907-15. [PMID: 22372922 DOI: 10.1111/j.1538-7836.2012.04673.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Platelets are specialized cells, produced by megakaryocytes (MKs) in the bone marrow, which represent the first defense against hemorrhage. There are many diseases where platelet production or function is impaired, with severe consequences for patients. Therefore, new insights into the process of MK differentiation and platelet formation would have a major impact on both basic and clinical research. OBJECTIVES Embryonic stem (ES) cells represent a good in vitro model to study the differentiation of MKs, with the possibility of being genetically engineered and constituting an unlimited source of MKs. However, lack of knowledge about the molecular identity of ES-derived MKs (ES-MKs) may prevent any further development and application of this model. METHODS This paper presents the first comprehensive transcriptional and proteome profile analyses of mouse ES-MKs in comparison with MKs derived from mouse fetal liver progenitors (FL-MKs). RESULTS In ES-MKs we found a down-regulation of cytoskeleton proteins, specific transcription factors and membrane receptors at both transcriptional and protein levels. At the phenotypic level, this molecular blueprint was displayed by ES-MKs' lower polyploidy, lower nuclear/cytoplasm ratio and reduced capacity to form proplatelets and releasing platelets. CONCLUSIONS Overall our data demonstrate that ES-MKs represent a useful model to clarify many aspects of both MK physiology and pathological conditions where impaired MK functions are related to defective MK development, as in inherited thrombocytopenias and primary myelofibrosis.
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Affiliation(s)
- V Merico
- Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie Lazzaro Spallanzani, University of Pavia, Pavia, Italy
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Fibronectin promotes proplatelet formation in the human megakaryocytic cell line UT-7/TPO. Cell Biol Int 2012; 36:39-45. [PMID: 21970435 DOI: 10.1042/cbi20110383] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We investigated PPF (proplatelet formation) in the human megakaryocytic cell line UT-7/TPO in vitro and signal transduction pathways responsible for PPF. The megakaryocytic cell lines are useful for studying megakaryocyte biology, although PPF is induced only in the presence of phorbol ester. TPO (thrombopoietin) stimulates megakaryocyte proliferation and differentiation; however, no PPF occurred in the megakaryocytic cell lines, even after the addition of TPO. Therefore, factors other than TPO may play an important role in the process of PPF. As PPF occurs in the bone marrow in vivo, we noted extracellular matrix proteins and found that soluble FN (fibronectin) induced potent PPF in UT-7/TPO without phorbol ester. A Western blot analysis showed that the expression of integrins was not increased by FN treatment. Anti-β1 antibody and the RGD (arginine-glycine-aspartate) peptide inhibited FN-induced PPF. This result indicates that the signal originated from integrin β1, which is essential to inducing PPF in UT-7/TPO. Results of the experiments using several inhibitors suggest that activation of the MEK [MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase]-ERK and PI3K (phosphoinositide 3-kinase) pathways are necessary for PPF. The phosphorylation of ERK gradually increased for 2 h after the addition of soluble FN, which suggests that activation of ERK is essential for the initial induction of FN-induced PPF in UT-7/TPO. UT-7/TPO is a useful cell line that enables us to study the signals of PPF without effects of chemical compounds.
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60
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Blood platelet production and morphology. Thromb Res 2012; 129:241-4. [PMID: 22226434 DOI: 10.1016/j.thromres.2011.11.042] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 11/22/2011] [Accepted: 11/24/2011] [Indexed: 01/02/2023]
Abstract
Circulating platelets are highly specialized cells produced by megakaryocytes (Mks) that participate in hemostatic and inflammatory functions. Despite their critical role little is known about the molecular mechanisms involved in their production from megakaryocytes, or about the pathogenesis of platelet disorders. Megakaryopoiesis occurs in a complex microenvironment within the bone marrow. The underlying relationships between Mk maturation and bone marrow components are key factors in this process. Mk interactions with extracellular matrices (ECM) via specific surface receptors control many functions, with chemistry, physical parameters and membrane elasticity as fundamental elements of the processes involved. Alteration of Mk-ECM interactions in the bone marrow environment may lead to pathophysiologic situations, such as myelofibrosis and congenital thrombocytopenia. Searching the mechanisms related to Mks-bone marrow environment interactions, will provide novel insight into fundamental control of Mk function, leading to new concepts in the study of Mk-related disease states and future modes for therapeutic inquiry.
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Celebi B, Mantovani D, Pineault N. Effects of extracellular matrix proteins on the growth of haematopoietic progenitor cells. Biomed Mater 2011; 6:055011. [PMID: 21931196 DOI: 10.1088/1748-6041/6/5/055011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Umbilical cord blood (UCB) transplantation and haematological recovery are currently limited by the amount of haematopoietic progenitor cells (HPCs) present in each unit. HPCs and haematopoietic stem cells (HSCs) normally interact with cells and extracellular matrix (ECM) proteins present within the endosteal and vascular niches. Hence, we investigated whether coating of culture surfaces with ECM proteins normally present in the marrow microenvironment could benefit the ex vivo expansion of HPCs. Towards this, collagen types I and IV (COL I and IV), laminin (LN) and fibronectin (FN) were tested individually or as component of two ECM-mix complexes. Individually, ECM proteins had both common and unique properties on the growth and differentiation of UCB CD34+ cells; some ECM proteins favoured the differentiation of some lineages over that of others (e.g. FN for erythroids), some the expansion of HPCs (e.g. LN and megakaryocyte (MK) progenitor) while others had less effects. Next, two ECM-mix complexes were tested; the first one contained all four ECM proteins (4ECMp), while the second 'basement membrane-like structure' was without COL I (3ECMp). Removal of COL I led to strong reductions in cell growth and HPCs expansion. Interestingly, the 4ECMp-mix complex reproducibly increased CD34+ (1.3-fold) and CD41+ (1.2-fold) cell expansions at day 6 (P < 0.05) versus control, and induced greater myeloid progenitor expansion (P < 0.05) than 3ECMp. In conclusion, these results suggest that optimization of BM ECM protein complexes could provide a better environment for the ex vivo expansion of haematopoietic progenitors than individual ECM protein.
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Affiliation(s)
- Betül Celebi
- Hema-Quebec, Research & Development Department, Quebec City, PQ, Canada
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62
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Abstract
Cell interactions with matrices via specific receptors control many functions, with chemistry, physics, and membrane elasticity as fundamental elements of the processes involved. Little is known about how biochemical and biophysical processes integrate to generate force and, ultimately, to regulate hemopoiesis into the bone marrow-matrix environment. To address this hypothesis, in this work we focus on the regulation of MK development by type I collagen. By atomic force microscopy analysis, we demonstrate that the tensile strength of fibrils in type I collagen structure is a fundamental requirement to regulate cytoskeleton contractility of human MKs through the activation of integrin-α2β1-dependent Rho-ROCK pathway and MLC-2 phosphorylation. Most importantly, this mechanism seemed to mediate MK migration, fibronectin assembly, and platelet formation. On the contrary, a decrease in mechanical tension caused by N-acetylation of lysine side chains in type I collagen completely reverted these processes by preventing fibrillogenesis.
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NBEAL2 is mutated in gray platelet syndrome and is required for biogenesis of platelet α-granules. Nat Genet 2011; 43:732-4. [PMID: 21765412 PMCID: PMC3154019 DOI: 10.1038/ng.883] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 06/15/2011] [Indexed: 11/30/2022]
Abstract
Gray Platelet Syndrome (GPS) is an autosomal recessive bleeding disorder with large platelets that lack α-granules. We found that mutations of NBEAL2 (neurobeachin-like 2), encoding a BEACH/ARM/WD40 domain protein, cause GPS. We demonstrated that human megakaryocytes and platelets express a unique combination of NBEAL2 transcripts. Proteomic analysis of sucrose-gradient subcellular fractions of platelets indicated that NBEAL2 localizes to the dense tubular system (endoplasmic reticulum) in platelets.
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