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Casas-Mao D, Carrington G, Pujol MG, Peckham M. Effects of specific disease mutations in non-muscle myosin 2A on its structure and function. J Biol Chem 2024; 300:105514. [PMID: 38042490 PMCID: PMC10770755 DOI: 10.1016/j.jbc.2023.105514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 12/04/2023] Open
Abstract
Non-muscle myosin 2A (NM2A), a widely expressed class 2 myosin, is important for organizing actin filaments in cells. It cycles between a compact inactive 10S state in which its regulatory light chain (RLC) is dephosphorylated and a filamentous state in which the myosin heads interact with actin, and the RLC is phosphorylated. Over 170 missense mutations in MYH9, the gene that encodes the NM2A heavy chain, have been described. These cause MYH9 disease, an autosomal-dominant disorder that leads to bleeding disorders, kidney disease, cataracts, and deafness. Approximately two-thirds of these mutations occur in the coiled-coil tail. These mutations could destabilize the 10S state and/or disrupt filament formation or both. To test this, we determined the effects of six specific mutations using multiple approaches, including circular dichroism to detect changes in secondary structure, negative stain electron microscopy to analyze 10S and filament formation in vitro, and imaging of GFP-NM2A in fixed and live cells to determine filament assembly and dynamics. Two mutations in D1424 (D1424G and D1424N) and V1516M strongly decrease 10S stability and have limited effects on filament formation in vitro. In contrast, mutations in D1447 and E1841K, decrease 10S stability less strongly but increase filament lengths in vitro. The dynamic behavior of all mutants was altered in cells. Thus, the positions of mutated residues and their roles in filament formation and 10S stabilization are key to understanding their contributions to NM2A in disease.
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Affiliation(s)
- David Casas-Mao
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Glenn Carrington
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Marta Giralt Pujol
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Michelle Peckham
- Astbury Centre for Structural Molecular Biology & School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
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2
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Das S, Mallick D, Sarkar S, Billington N, Sellers JR, Jana SS. A brain specific alternatively spliced isoform of nonmuscle myosin IIA lacks its mechanoenzymatic activities. J Biol Chem 2023; 299:105143. [PMID: 37562567 PMCID: PMC10480317 DOI: 10.1016/j.jbc.2023.105143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 08/12/2023] Open
Abstract
Recent genomic studies reported that 90 to 95% of human genes can undergo alternative splicing, by which multiple isoforms of proteins are synthesized. However, the functional consequences of most of the isoforms are largely unknown. Here, we report a novel alternatively spliced isoform of nonmuscle myosin IIA (NM IIA), called NM IIA2, which is generated by the inclusion of 21 amino acids near the actin-binding region (loop 2) of the head domain of heavy chains. Expression of NM IIA2 is found exclusively in the brain tissue, where it reaches a maximum level at 24 h during the circadian rhythm. The actin-dependent Mg2+-ATPase activity and in vitro motility assays reveal that NM IIA2 lacks its motor activities but localizes with actin filaments in cells. Interestingly, NM IIA2 can also make heterofilaments with NM IIA0 (noninserted isoform of NM IIA) and can retard the in vitro motility of NM IIA, when the two are mixed. Altogether, our findings provide the functional importance of a previously unknown alternatively spliced isoform, NM IIA2, and its potential physiological role in regulating NM IIA activity in the brain.
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Affiliation(s)
- Samprita Das
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata, West Bengal, India
| | - Ditipriya Mallick
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata, West Bengal, India
| | - Sourav Sarkar
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata, West Bengal, India
| | - Neil Billington
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - James R Sellers
- Laboratory of Molecular Physiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
| | - Siddhartha S Jana
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata, West Bengal, India.
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3
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Islam ST, Cheng C, Parreno J, Fowler VM. Nonmuscle Myosin IIA Regulates the Precise Alignment of Hexagonal Eye Lens Epithelial Cells During Fiber Cell Formation and Differentiation. Invest Ophthalmol Vis Sci 2023; 64:20. [PMID: 37070941 PMCID: PMC10123325 DOI: 10.1167/iovs.64.4.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 03/27/2023] [Indexed: 04/19/2023] Open
Abstract
Purpose Epithelial cells in the equatorial region of the ocular lens undergo a remarkable transition from randomly packed cells into precisely aligned and hexagon-shaped cells organized into meridional rows. We investigated the function of nonmuscle myosin IIA (encoded by Myh9) in regulating equatorial epithelial cell alignment to form meridional rows during secondary fiber cell morphogenesis. Methods We used genetic knock-in mice to study a common human Myh9 mutation, E1841K, in the rod domain. The E1841K mutation disrupts bipolar filament assembly. Lens shape, clarity, and stiffness were evaluated, and Western blots were used to determine the level of normal and mutant myosins. Cryosections and lens whole mounts were stained and imaged by confocal microscopy to investigate cell shape and organization. Results We observed no obvious changes in lens size, shape, and biomechanical properties (stiffness and resilience) between the control and nonmuscle myosin IIA-E1841K mutant mice at 2 months of age. Surprisingly, we found misalignment and disorder of fiber cells in heterozygous and homozygous mutant lenses. Further analysis revealed misshapen equatorial epithelial cells that cause disorientation of the meridional rows before fiber cell differentiation in homozygous mutant lenses. Conclusions Our data indicate that nonmuscle myosin IIA bipolar filament assembly is required for the precise alignment of the meridional rows at the lens equator and that the organization of lens fiber cells depends on the proper patterning of meridional row epithelial cells. These data also suggest that lens fiber cell organization and a hexagonal shape are not required for normal lens size, shape transparency, or biomechanical properties.
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Affiliation(s)
- Sadia T. Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Justin Parreno
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Velia M. Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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Nangia-Makker P, Shekhar MP, Hogan V, Balan V, Raz A. MYH9 binds to dNTPs via deoxyribose moiety and plays an important role in DNA synthesis. Oncotarget 2022; 13:534-550. [PMID: 35309869 PMCID: PMC8923078 DOI: 10.18632/oncotarget.28219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/04/2022] [Indexed: 11/25/2022] Open
Abstract
The accepted notion of dNTP transport following cytoplasmic biosynthesis is 'facilitated diffusion'; however, whether this alone is sufficient for moving dNTPs for DNA synthesis remains an open question. The data presented here show that the MYH9 gene encoded heavy chain of non-muscle myosin IIA binds dNTPs potentially serving as a 'reservoir'. Pull-down assays showed that MYH9 present in the cytoplasmic, mitochondrial and nuclear compartments bind to DNA and this interaction is inhibited by dNTPs and 2-deoxyribose-5-phosphate (dRP) suggesting that MYH9-DNA binding is mediated via pentose sugar recognition. Direct dNTP-MYH9 binding was demonstrated by ELISA and a novel PCR-based method, which showed that all dNTPs bind to MYH9 with varying efficiencies. Cellular thermal shift assays showed that MYH9 thermal stability is enhanced by dNTPs. MYH9 siRNA transfection or treatment with myosin II selective inhibitors ML7 or blebbistatin decreased cell proliferation compared to controls. EdU labeling and cell cycle analysis by flow cytometry confirmed MYH9 siRNA and myosin II inhibitors decreased progression to S-phase with accumulation of cells in G0/G1 phase. Taken together, our data suggest a novel role for MYH9 in dNTP binding and DNA synthesis.
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Affiliation(s)
- Pratima Nangia-Makker
- Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
| | - Malathy P.V. Shekhar
- Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Pathology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
| | - Victor Hogan
- Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI 48201, USA
| | | | - Avraham Raz
- Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Oncology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
- Department of Pathology, School of Medicine, Wayne State University, Detroit, MI 48201, USA
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Ismail TM, Gross SR, Lancaster T, Rudland PS, Barraclough R. The Role of the C-Terminal Lysine of S100P in S100P-Induced Cell Migration and Metastasis. Biomolecules 2021; 11:biom11101471. [PMID: 34680103 PMCID: PMC8533620 DOI: 10.3390/biom11101471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 09/29/2021] [Accepted: 10/02/2021] [Indexed: 11/16/2022] Open
Abstract
S100P protein is a potent inducer of metastasis in a model system, and its presence in cancer cells of patients is strongly associated with their reduced survival times. A well-established Furth Wistar rat metastasis model system, methods for measuring cell migration, and specific inhibitors were used to study pathways of motility-driven metastasis. Cells expressing C-terminal mutant S100P proteins display markedly-reduced S100P-driven metastasis in vivo and cell migration in vitro. These cells fail to display the low focal adhesion numbers observed in cells expressing wild-type S100P, and the mutant S100P proteins exhibit reduced biochemical interaction with non-muscle myosin heavy chain isoform IIA in vitro. Extracellular inhibitors of the S100P-dependent plasminogen activation pathway reduce, but only in part, wild-type S100P-dependent cell migration; they are without effect on S100P-negative cells or cells expressing C-terminal mutant S100P proteins and have no effect on the numbers of focal adhesions. Recombinant wild-type S100P protein, added extracellularly to S100P-negative cells, stimulates cell migration, which is abolished by these inhibitors. The results identify at least two S100P-dependent pathways of migration, one cell surface and the other intracellularly-linked, and identify its C-terminal lysine as a target for inhibiting multiple migration-promoting activities of S100P protein and S100P-driven metastasis.
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Affiliation(s)
- Thamir M. Ismail
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK; (T.M.I.); (P.S.R.)
| | - Stephane R. Gross
- College of Health and Life Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK;
- Correspondence: (S.R.G.); (R.B.)
| | - Tara Lancaster
- College of Health and Life Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK;
| | - Philip S. Rudland
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK; (T.M.I.); (P.S.R.)
| | - Roger Barraclough
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK; (T.M.I.); (P.S.R.)
- Correspondence: (S.R.G.); (R.B.)
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Lee CP, Ko AMS, Nithiyanantham S, Lai CH, Ko YC. Long noncoding RNA HAR1A regulates oral cancer progression through the alpha-kinase 1, bromodomain 7, and myosin IIA axis. J Mol Med (Berl) 2021; 99:1323-1334. [PMID: 34097087 DOI: 10.1007/s00109-021-02095-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 04/19/2021] [Accepted: 05/13/2021] [Indexed: 02/07/2023]
Abstract
Studies suggested that long noncoding HAR1A RNA may be a tumor suppressor, but its association with oral cancer remains unclear. Here, we show the functional role and mechanisms of HAR1A in oral cancer progression. Microarray analysis was performed to screen the related candidates of long noncoding RNA (lncRNA) in human monocytes. Following lncRNA HAR1A, the regulation of HAR1A, ALPK1, myosin IIA, and BRD7 was tested using reverse-transcription quantitative polymerase chain reaction (RT-qPCR) in oral cancer cells. The inflammatory and epithelial-to-mesenchymal transition marker expressions were analyzed using enzyme-linked immunosorbent assay and western blot. Phenotypic experiments were verified by colony formation assay, transwell migration assay, and Annexin V-apoptotic assay. In the nuclei of cancer cells, HAR1A functions upstream of signaling pathways and knockdown of HAR1A promoted ALPK1 expression and downregulated BRD7 resulting in inflammation and oral cancer progression. In monocytes, the expressions of TNF-α and CCL2 were increased following HAR1A knockdown and reduced following ALPK1 knockdown. HAR1A knockdown upregulated the expression of ALPK1, slug, vimentin, fibronectin, and N-cadherin but reduced the expression of E-cadherin in oral cancer cells. Myosin IIA was primarily located in the cytoplasm and that its decrease in the nuclei of oral cancer cells was likely to demonstrate suppressive ability in late-stage cancer. Our findings suggest that the HAR1A, BRD7, and myosin IIA are tumor suppressors while ALPK1 has oncogene-like property in the nucleus and is involved in inflammation and oral cancer progression. More research for HAR1A activators or ALPK1 inhibitors is required to develop potential therapeutic agents for advanced oral cancer. KEY MESSAGES: lncRNA HAR1A, BRD7, and myosin IIA are tumor suppressors whereas ALPK1 has an oncogenic-like property in the nucleus. lncRNA HAR1A/ALPK1/BRD7/myosin IIA axis plays a critical role in the progression of oral cancer. lncRNA HAR1A localizes upstream of signaling pathways to inhibit ALPK1 expression and then upregulated BRD7. lncRNA HAR1A and ALPK1 are involved in cancer progression via epithelial-to-mesenchymal transition regulations. ALPK1 inhibitors are potential kinase-targeted therapeutic agents for patients with advanced oral cancer.
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Affiliation(s)
- Chi-Pin Lee
- Environment-Omics-Disease Research Center, China Medical University Hospital, China Medical University, No. 2 Yude Road, Taichung, 40447, Taiwan
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, 40402, Taiwan
| | - Albert Min-Shan Ko
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, CAS, Beijing, 100044, China
| | - Srinivasan Nithiyanantham
- Environment-Omics-Disease Research Center, China Medical University Hospital, China Medical University, No. 2 Yude Road, Taichung, 40447, Taiwan
| | - Chu-Hu Lai
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung, 41354, Taiwan
| | - Ying-Chin Ko
- Environment-Omics-Disease Research Center, China Medical University Hospital, China Medical University, No. 2 Yude Road, Taichung, 40447, Taiwan.
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Sharlo KA, Paramonova II, Lvova ID, Mochalova EP, Kalashnikov VE, Vilchinskaya NA, Tyganov SA, Konstantinova TS, Shevchenko TF, Kalamkarov GR, Shenkman BS. Plantar Mechanical Stimulation Maintains Slow Myosin Expression in Disused Rat Soleus Muscle via NO-Dependent Signaling. Int J Mol Sci 2021; 22:1372. [PMID: 33573052 PMCID: PMC7866401 DOI: 10.3390/ijms22031372] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/23/2021] [Accepted: 01/26/2021] [Indexed: 11/17/2022] Open
Abstract
It was observed that gravitational unloading during space missions and simulated microgravity in ground-based studies leads to both transformation of slow-twitch muscle fibers into fast-twitch fibers and to the elimination of support afferentation, leading to the "switching-off" of postural muscle motor units electrical activity. In recent years, plantar mechanical stimulation (PMS) has been found to maintain the neuromuscular activity of the hindlimb muscles. Nitric oxide (NO) was shown to be one of the mediators of muscle fiber activity, which can also promote slow-type myosin expression. We hypothesized that applying PMS during rat hindlimb unloading would lead to NO production upregulation and prevention of the unloading-induced slow-to-fast fiber-type shift in rat soleus muscles. To test this hypothesis, Wistar rats were hindlimb suspended and subjected to daily PMS, and one group of PMS-subjected animals was also treated with nitric oxide synthase inhibitor (L-NAME). We discovered that PMS led to sustained NO level in soleus muscles of the suspended animals, and NOS inhibitor administration blocked this effect, as well as the positive effects of PMS on myosin I and IIa mRNA transcription and slow-to-fast fiber-type ratio during rat hindlimb unloading. The results of the study indicate that NOS activity is necessary for the PMS-mediated prevention of slow-to-fast fiber-type shift and myosin I and IIa mRNA transcription decreases during rat hindlimb unloading.
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Affiliation(s)
- Kristina A. Sharlo
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Inna I. Paramonova
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Irina D. Lvova
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Ekaterina P. Mochalova
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Vitaliy E. Kalashnikov
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Natalia A. Vilchinskaya
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Sergey A. Tyganov
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
| | - Tatyana S. Konstantinova
- Emanuel Institute of Biochemical Physics, RAS, 123007 Moscow, Russia; (T.S.K.); (T.F.S.); (G.R.K.)
| | - Tatiana F. Shevchenko
- Emanuel Institute of Biochemical Physics, RAS, 123007 Moscow, Russia; (T.S.K.); (T.F.S.); (G.R.K.)
| | - Grigoriy R. Kalamkarov
- Emanuel Institute of Biochemical Physics, RAS, 123007 Moscow, Russia; (T.S.K.); (T.F.S.); (G.R.K.)
| | - Boris S. Shenkman
- Myology Laboratory, Institute of Biomedical Problems RAS, 123007 Moscow, Russia; (K.A.S.); (I.D.L.); (E.P.M.); (V.E.K.); (N.A.V.); (S.A.T.); (B.S.S.)
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Subramanian BC, Melis N, Chen D, Wang W, Gallardo D, Weigert R, Parent CA. The LTB4-BLT1 axis regulates actomyosin and β2-integrin dynamics during neutrophil extravasation. J Cell Biol 2020; 219:e201910215. [PMID: 32854115 PMCID: PMC7659729 DOI: 10.1083/jcb.201910215] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 06/17/2020] [Accepted: 07/23/2020] [Indexed: 12/13/2022] Open
Abstract
The eicosanoid leukotriene B4 (LTB4) relays chemotactic signals to direct neutrophil migration to inflamed sites through its receptor BLT1. However, the mechanisms by which the LTB4-BLT1 axis relays chemotactic signals during intravascular neutrophil response to inflammation remain unclear. Here, we report that LTB4 produced by neutrophils acts as an autocrine/paracrine signal to direct the vascular recruitment, arrest, and extravasation of neutrophils in a sterile inflammation model in the mouse footpad. Using intravital subcellular microscopy, we reveal that LTB4 elicits sustained cell polarization and adhesion responses during neutrophil arrest in vivo. Specifically, LTB4 signaling coordinates the dynamic redistribution of non-muscle myosin IIA and β2-integrin, which facilitate neutrophil arrest and extravasation. Notably, we also found that neutrophils shed extracellular vesicles in the vascular lumen and that inhibition of extracellular vesicle release blocks LTB4-mediated autocrine/paracrine signaling required for neutrophil arrest and extravasation. Overall, we uncover a novel complementary mechanism by which LTB4 relays extravasation signals in neutrophils during early inflammation response.
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Affiliation(s)
- Bhagawat C. Subramanian
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Nicolas Melis
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Desu Chen
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Weiye Wang
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Devorah Gallardo
- Laboratory Animal Sciences Program, Leidos Biomedical Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Roberto Weigert
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Carole A. Parent
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD
- Department of Pharmacology, University of Michigan, Ann Arbor, MI
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Asensio-Juárez G, Llorente-González C, Vicente-Manzanares M. Linking the Landscape of MYH9-Related Diseases to the Molecular Mechanisms that Control Non-Muscle Myosin II-A Function in Cells. Cells 2020; 9:E1458. [PMID: 32545517 PMCID: PMC7348894 DOI: 10.3390/cells9061458] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 12/13/2022] Open
Abstract
The MYH9 gene encodes the heavy chain (MHCII) of non-muscle myosin II A (NMII-A). This is an actin-binding molecular motor essential for development that participates in many crucial cellular processes such as adhesion, cell migration, cytokinesis and polarization, maintenance of cell shape and signal transduction. Several types of mutations in the MYH9 gene cause an array of autosomal dominant disorders, globally known as MYH9-related diseases (MYH9-RD). These include May-Hegglin anomaly (MHA), Epstein syndrome (EPS), Fechtner syndrome (FTS) and Sebastian platelet syndrome (SPS). Although caused by different MYH9 mutations, all patients present macrothrombocytopenia, but may later display other pathologies, including loss of hearing, renal failure and presenile cataracts. The correlation between the molecular and cellular effects of the different mutations and clinical presentation are beginning to be established. In this review, we correlate the defects that MYH9 mutations cause at a molecular and cellular level (for example, deficient filament formation, altered ATPase activity or actin-binding) with the clinical presentation of the syndromes in human patients. We address why these syndromes are tissue restricted, and the existence of possible compensatory mechanisms, including residual activity of mutant NMII-A and/ or the formation of heteropolymers or co-polymers with other NMII isoforms.
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Affiliation(s)
| | | | - Miguel Vicente-Manzanares
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-University of Salamanca, 37007 Salamanca, Spain; (G.A.-J.); (C.L.-G.)
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10
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Pecci A, Ma X, Savoia A, Adelstein RS. MYH9: Structure, functions and role of non-muscle myosin IIA in human disease. Gene 2018; 664:152-167. [PMID: 29679756 PMCID: PMC5970098 DOI: 10.1016/j.gene.2018.04.048] [Citation(s) in RCA: 160] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
The MYH9 gene encodes the heavy chain of non-muscle myosin IIA, a widely expressed cytoplasmic myosin that participates in a variety of processes requiring the generation of intracellular chemomechanical force and translocation of the actin cytoskeleton. Non-muscle myosin IIA functions are regulated by phosphorylation of its 20 kDa light chain, of the heavy chain, and by interactions with other proteins. Variants of MYH9 cause an autosomal-dominant disorder, termed MYH9-related disease, and may be involved in other conditions, such as chronic kidney disease, non-syndromic deafness, and cancer. This review discusses the structure of the MYH9 gene and its protein, as well as the regulation and physiologic functions of non-muscle myosin IIA with particular reference to embryonic development. Moreover, the review focuses on current knowledge about the role of MYH9 variants in human disease.
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Affiliation(s)
- Alessandro Pecci
- Department of Internal Medicine, IRCCS Policlinico San Matteo Foundation, University of Pavia, Piazzale Golgi, 27100 Pavia, Italy.
| | - Xuefei Ma
- Laboratory of Molecular Cardiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bldg. 10 Room 6C-103B, 10 Center Drive, Bethesda, MD 20892-1583, USA.
| | - Anna Savoia
- Department of Medical Sciences, University of Trieste, via Dell'Istria, 65/1, I-34137 Trieste, Italy; IRCCS Burlo Garofolo, via Dell'Istria, 65/1, I-34137 Trieste, Italy.
| | - Robert S Adelstein
- Laboratory of Molecular Cardiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bldg. 10 Room 6C-103B, 10 Center Drive, Bethesda, MD 20892-1583, USA.
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11
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Liu T, Hu Y, Guo S, Tan L, Zhan Y, Yang L, Liu W, Wang N, Li Y, Zhang Y, Liu C, Yang Y, Adelstein RS, Wang A. Identification and characterization of MYH9 locus for high efficient gene knock-in and stable expression in mouse embryonic stem cells. PLoS One 2018; 13:e0192641. [PMID: 29438440 PMCID: PMC5811019 DOI: 10.1371/journal.pone.0192641] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/26/2018] [Indexed: 01/22/2023] Open
Abstract
Targeted integration of exogenous genes into so-called safe harbors/friend sites, offers the advantages of expressing normal levels of target genes and preventing potentially adverse effects on endogenous genes. However, the ideal genomic loci for this purpose remain limited. Additionally, due to the inherent and unresolved issues with the current genome editing tools, traditional embryonic stem (ES) cell-based targeted transgenesis technology is still preferred in practical applications. Here, we report that a high and repeatable homologous recombination (HR) frequency (>95%) is achieved when an approximate 6kb DNA sequence flanking the MYH9 gene exon 2 site is used to create the homology arms for the knockout/knock-in of diverse nonmuscle myosin II (NM II) isoforms in mouse ES cells. The easily obtained ES clones greatly facilitated the generation of multiple NM II genetic replacement mouse models, as characterized previously. Further investigation demonstrated that though the targeted integration site for exogenous genes is shifted to MYH9 intron 2 (about 500bp downstream exon 2), the high HR efficiency and the endogenous MYH9 gene integrity are not only preserved, but the expected expression of the inserted gene(s) is observed in a pre-designed set of experiments conducted in mouse ES cells. Importantly, we confirmed that the expression and normal function of the endogenous MYH9 gene is not affected by the insertion of the exogenous gene in these cases. Therefore, these findings suggest that like the commonly used ROSA26 site, the MYH9 gene locus may be considered a new safe harbor for high-efficiency targeted transgenesis and for biomedical applications.
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Affiliation(s)
- Tanbin Liu
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Yi Hu
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Shiyin Guo
- College of Food Science and Technology, HUNAU, Changsha, Hunan, China
| | - Lei Tan
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Yang Zhan
- Lab of Functional Proteomics (LFP), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, HUNAU, Changsha, Hunan, China
| | - Lingchen Yang
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Wei Liu
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Naidong Wang
- Lab of Functional Proteomics (LFP), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, HUNAU, Changsha, Hunan, China
| | - Yalan Li
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
| | - Yingfan Zhang
- Lab of Molecular Cardiology (LMC), National Heart, Lung, and Blood Institute (NHLBI)/National Institutes of Health (NIH), Bethesda, MD, United States of America
| | - Chengyu Liu
- Transgenic Core, NHLBI/ NIH, Bethesda, MD, United States of America
| | - Yi Yang
- Lab of Functional Proteomics (LFP), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, HUNAU, Changsha, Hunan, China
| | - Robert S. Adelstein
- Lab of Molecular Cardiology (LMC), National Heart, Lung, and Blood Institute (NHLBI)/National Institutes of Health (NIH), Bethesda, MD, United States of America
| | - Aibing Wang
- Lab of Animal Models and Functional Genomics (LAMFG), The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University (HUNAU), Changsha, Hunan, China
- Lab of Molecular Cardiology (LMC), National Heart, Lung, and Blood Institute (NHLBI)/National Institutes of Health (NIH), Bethesda, MD, United States of America
- * E-mail:
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12
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Haque F, Kaku Y, Fujimura S, Ohmori T, Adelstein RS, Nishinakamura R. Non-muscle myosin II deletion in the developing kidney causes ureter-bladder misconnection and apical extrusion of the nephric duct lineage epithelia. Dev Biol 2017; 427:121-130. [PMID: 28478097 DOI: 10.1016/j.ydbio.2017.04.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 04/27/2017] [Accepted: 04/29/2017] [Indexed: 01/23/2023]
Abstract
In kidney development, connection of the nephric duct (ND) to the cloaca and subsequent sprouting of the ureteric bud (UB) from the ND are important for urinary exit tract formation. Although the roles of Ret signaling are well established, it remains unclear how intracellular cytoskeletal proteins regulate these morphogenetic processes. Myh9 and Myh10 encode two different non-muscle myosin II heavy chains, and Myh9 mutations in humans are implicated in congenital kidney diseases. Here we report that ND/UB lineage-specific deletion of Myh9/Myh10 in mice caused severe hydroureter/hydronephrosis at birth. At mid-gestation, the mutant ND/UB epithelia exhibited aberrant basal protrusion and ectopic UB formation, which likely led to misconnection of the ureter to the bladder. In addition, the mutant epithelia exhibited apical extrusion followed by massive apoptosis in the lumen, which could be explained by reduced apical constriction and intercellular adhesion mediated by E-cadherin. These phenotypes were not ameliorated by genetic reduction of the tyrosine kinase receptor Ret. In contrast, ERK was activated in the mutant cells and its chemical inhibition partially ameliorated the phenotypes. Thus, myosin II is essential for maintaining the apicobasal integrity of the developing kidney epithelia independently of Ret signaling.
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Affiliation(s)
- Fahim Haque
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Yusuke Kaku
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Sayoko Fujimura
- Liaison Laboratory Research Promotion Center, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Tomoko Ohmori
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Robert S Adelstein
- Laboratory of Molecular Cardiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ryuichi Nishinakamura
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.
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Hindman B, Goeckeler Z, Sierros K, Wysolmerski R. Non-Muscle Myosin II Isoforms Have Different Functions in Matrix Rearrangement by MDA-MB-231 Cells. PLoS One 2015; 10:e0131920. [PMID: 26136073 PMCID: PMC4489869 DOI: 10.1371/journal.pone.0131920] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 06/08/2015] [Indexed: 01/15/2023] Open
Abstract
The role of a stiffening extra-cellular matrix (ECM) in cancer progression is documented but poorly understood. Here we use a conditioning protocol to test the role of nonmuscle myosin II isoforms in cell mediated ECM arrangement using collagen constructs seeded with breast cancer cells expressing shRNA targeted to either the IIA or IIB heavy chain isoform. While there are several methods available to measure changes in the biophysical characteristics of the ECM, we wanted to use a method which allows for the measurement of global stiffness changes as well as a dynamic response from the sample over time. The conditioning protocol used allows the direct measurement of ECM stiffness. Using various treatments, it is possible to determine the contribution of various construct and cellular components to the overall construct stiffness. Using this assay, we show that both the IIA and IIB isoforms are necessary for efficient matrix remodeling by MDA-MB-231 breast cancer cells, as loss of either isoform changes the stiffness of the collagen constructs as measured using our conditioning protocol. Constructs containing only collagen had an elastic modulus of 0.40 Pascals (Pa), parental MDA-MB-231 constructs had an elastic modulus of 9.22 Pa, while IIA and IIB KD constructs had moduli of 3.42 and 7.20 Pa, respectively. We also calculated the cell and matrix contributions to the overall sample elastic modulus. Loss of either myosin isoform resulted in decreased cell stiffness, as well as a decrease in the stiffness of the cell-altered collagen matrices. While the total construct modulus for the IIB KD cells was lower than that of the parental cells, the IIB KD cell-altered matrices actually had a higher elastic modulus than the parental cell-altered matrices (4.73 versus 4.38 Pa). These results indicate that the IIA and IIB heavy chains play distinct and non-redundant roles in matrix remodeling.
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Affiliation(s)
- Bridget Hindman
- Mary Babb Randolph Cancer Center, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown, West Virginia, United States of America
| | - Zoe Goeckeler
- Center for Cardiovascular and Respiratory Diseases, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown, West Virginia, United States of America
| | - Kostas Sierros
- Mechanical and Aerospace Engineering, Statler College of Engineering and Mineral Resources, West Virginia University, Morgantown, West Virginia, United States of America
| | - Robert Wysolmerski
- Mary Babb Randolph Cancer Center, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown, West Virginia, United States of America
- Center for Cardiovascular and Respiratory Diseases, West Virginia University, Robert C. Byrd Health Sciences Center, Morgantown, West Virginia, United States of America
- * E-mail:
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Frénal K, Marq JB, Jacot D, Polonais V, Soldati-Favre D. Plasticity between MyoC- and MyoA-glideosomes: an example of functional compensation in Toxoplasma gondii invasion. PLoS Pathog 2014; 10:e1004504. [PMID: 25393004 PMCID: PMC4231161 DOI: 10.1371/journal.ppat.1004504] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 10/06/2014] [Indexed: 11/23/2022] Open
Abstract
The glideosome is an actomyosin-based machinery that powers motility in Apicomplexa and participates in host cell invasion and egress from infected cells. The central component of the glideosome, myosin A (MyoA), is a motor recruited at the pellicle by the acylated gliding-associated protein GAP45. In Toxoplasma gondii, GAP45 also contributes to the cohesion of the pellicle, composed of the inner membrane complex (IMC) and the plasma membrane, during motor traction. GAP70 was previously identified as a paralog of GAP45 that is tailored to recruit MyoA at the apical cap in the coccidian subgroup of the Apicomplexa. A third member of this family, GAP80, is demonstrated here to assemble a new glideosome, which recruits the class XIV myosin C (MyoC) at the basal polar ring. MyoC shares the same myosin light chains as MyoA and also interacts with the integral IMC proteins GAP50 and GAP40. Moreover, a central component of this complex, the IMC-associated protein 1 (IAP1), acts as the key determinant for the restricted localization of MyoC to the posterior pole. Deletion of specific components of the MyoC-glideosome underscores the installation of compensatory mechanisms with components of the MyoA-glideosome. Conversely, removal of MyoA leads to the relocalization of MyoC along the pellicle and at the apical cap that accounts for residual invasion. The two glideosomes exhibit a considerable level of plasticity to ensure parasite survival. Toxoplasma gondii can infect most warm-blooded animals, and is an important opportunistic pathogen for humans. This obligate intracellular parasite is able to invade virtually all nucleated cells, and as with most parasites of the Apicomplexa phylum, relies on a substrate-dependent gliding motility to actively penetrate into host cells and egress from infected cells. The conserved molecular machine (named glideosome) powering motility is located at the periphery of the parasite and involves the molecular motor, myosin A (MyoA). The glideosome exists in three flavors, exhibiting the same overall organization and sharing some common components while being spatially restricted to the central IMC, the apical cap and the basal pole of the parasite, respectively. The central and apical glideosomes are associated with MyoA (MyoA-glideosome) whereas the basal complex recruits myosin C (MyoC). Deleting components of the MyoC-glideosome uncovers the existence of complementary and compensatory mechanisms that ensure successful establishment of infection. This study highlights a higher degree of complexity and plasticity of the gliding machinery.
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Affiliation(s)
- Karine Frénal
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
- * E-mail:
| | - Jean-Baptiste Marq
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
| | - Damien Jacot
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
| | - Valérie Polonais
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
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Egarter S, Andenmatten N, Jackson AJ, Whitelaw JA, Pall G, Black JA, Ferguson DJP, Tardieux I, Mogilner A, Meissner M. The toxoplasma Acto-MyoA motor complex is important but not essential for gliding motility and host cell invasion. PLoS One 2014; 9:e91819. [PMID: 24632839 PMCID: PMC3954763 DOI: 10.1371/journal.pone.0091819] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 02/13/2014] [Indexed: 12/23/2022] Open
Abstract
Apicomplexan parasites are thought to actively invade the host cell by gliding motility. This movement is powered by the parasite's own actomyosin system, and depends on the regulated polymerisation and depolymerisation of actin to generate the force for gliding and host cell penetration. Recent studies demonstrated that Toxoplasma gondii can invade the host cell in the absence of several core components of the invasion machinery, such as the motor protein myosin A (MyoA), the microneme proteins MIC2 and AMA1 and actin, indicating the presence of alternative invasion mechanisms. Here the roles of MyoA, MLC1, GAP45 and Act1, core components of the gliding machinery, are re-dissected in detail. Although important roles of these components for gliding motility and host cell invasion are verified, mutant parasites remain invasive and do not show a block of gliding motility, suggesting that other mechanisms must be in place to enable the parasite to move and invade the host cell. A novel, hypothetical model for parasite gliding motility and invasion is presented based on osmotic forces generated in the cytosol of the parasite that are converted into motility.
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Affiliation(s)
- Saskia Egarter
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Nicole Andenmatten
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Allison J. Jackson
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jamie A. Whitelaw
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Gurman Pall
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jennifer Ann Black
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, Oxford University, Oxford, United Kingdom
| | - Isabelle Tardieux
- Institut Cochin, University of Paris Descartes, INSERM U-1016, CNRS UMR-8104, Paris, France
| | - Alex Mogilner
- Department of Neurobiology, Physiology, and Behavior and Department of Mathematics, University of California Davis, Davis, California, United States of America
| | - Markus Meissner
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
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16
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Suzuki N, Kunishima S, Naoe T, Matsushita T. [Animal models of MYH9 disorders]. Rinsho Ketsueki 2013; 54:2031-2037. [PMID: 24305535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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17
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Woody S, Stall R, Ramos J, Patel YM. Regulation of myosin light chain kinase during insulin-stimulated glucose uptake in 3T3-L1 adipocytes. PLoS One 2013; 8:e77248. [PMID: 24116218 PMCID: PMC3792908 DOI: 10.1371/journal.pone.0077248] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/09/2013] [Indexed: 11/25/2022] Open
Abstract
Myosin II (MyoII) is required for insulin-responsive glucose transporter 4 (GLUT4)-mediated glucose uptake in 3T3-L1 adipocytes. Our previous studies have shown that insulin signaling stimulates phosphorylation of the regulatory light chain (RLC) of MyoIIA via myosin light chain kinase (MLCK). The experiments described here delineate upstream regulators of MLCK during insulin-stimulated glucose uptake. Since 3T3-L1 adipocytes express two MyoII isoforms, we wanted to determine which isoform was required for insulin-stimulated glucose uptake. Using a siRNA approach, we demonstrate that a 60% decrease in MyoIIA protein expression resulted in a 40% inhibition of insulin-stimulated glucose uptake. We also show that insulin signaling stimulates the phosphorylation of MLCK. We further show that MLCK can be activated by calcium as well as signaling pathways. We demonstrate that adipocytes treated with the calcium chelating agent, 1,2-b (iso-aminophenoxy) ethane-N,N,N',N'-tetra acetic acid, (BAPTA) (in the presence of insulin) impaired the insulin-induced phosphorylation of MLCK by 52% and the RLC of MyoIIA by 45% as well as impairing the recruitment of MyoIIA to the plasma membrane when compared to cells treated with insulin alone. We further show that the calcium ionophore, A23187 alone stimulated the phosphorylation of MLCK and the RLC associated with MyoIIA to the same extent as insulin. To identify signaling pathways that might regulate MLCK, we examined ERK and CaMKII. Inhibition of ERK2 impaired phosphorylation of MLCK and insulin-stimulated glucose uptake. In contrast, while inhibition of CaMKII did inhibit phosphorylation of the RLC associated with MyoIIA, inhibition of CAMKIIδ did not impair MLCK phosphorylation or translocation to the plasma membrane or glucose uptake. Collectively, our results are the first to delineate a role for calcium and ERK in the activation of MLCK and thus MyoIIA during insulin-stimulated glucose uptake in 3T3-L1 adipocytes.
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Affiliation(s)
- Shelly Woody
- Department of Biology, University of North Carolina at Greensboro, Greensboro, North Carolina, United States of America
| | - Richard Stall
- Department of Biology, University of North Carolina at Greensboro, Greensboro, North Carolina, United States of America
| | - Joseph Ramos
- Department of Biology, University of North Carolina at Greensboro, Greensboro, North Carolina, United States of America
| | - Yashomati M. Patel
- Department of Biology, University of North Carolina at Greensboro, Greensboro, North Carolina, United States of America
- * E-mail:
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18
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Jacobelli J, Estin Matthews M, Chen S, Krummel MF. Activated T cell trans-endothelial migration relies on myosin-IIA contractility for squeezing the cell nucleus through endothelial cell barriers. PLoS One 2013; 8:e75151. [PMID: 24069389 PMCID: PMC3777879 DOI: 10.1371/journal.pone.0075151] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/11/2013] [Indexed: 01/09/2023] Open
Abstract
Following activation, T cells are released from lymph nodes to traffic via the blood to effector sites. The re-entry of these activated T cells into tissues represents a critical step for them to carry out local effector functions. Here we have assessed defects in effector T cells that are acutely depleted in Myosin-IIA (MyoIIA) and show a T cell intrinsic requirement for this motor to facilitate the diapedesis step of extravasation. We show that MyoIIA accumulates at the rear of T cells undergoing trans-endothelial migration. T cells can extend protrusions and project a substantial portion of their cytoplasm through the endothelial wall in the absence of MyoIIA. However, this motor protein plays a crucial role in allowing T cells to complete the movement of their relatively rigid nucleus through the endothelial junctions. In vivo, this defect manifests as poor entry into lymph nodes, tumors and into the spinal cord, during tissue-specific autoimmunity, but not the spleen. This suggests that therapeutic targeting of this molecule may allow for differential attenuation of tissue-specific inflammatory responses.
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Affiliation(s)
- Jordan Jacobelli
- Integrated Department of Immunology, National Jewish Health and University of Colorado Denver, Denver, Colorado, United States of America
- * E-mail: (JJ); (MFK)
| | - Miriam Estin Matthews
- Integrated Department of Immunology, National Jewish Health and University of Colorado Denver, Denver, Colorado, United States of America
| | - Stephanie Chen
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Matthew F. Krummel
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail: (JJ); (MFK)
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Kimura J, Ichii O, Otsuka S, Sasaki H, Hashimoto Y, Kon Y. Close relations between podocyte injuries and membranous proliferative glomerulonephritis in autoimmune murine models. Am J Nephrol 2013; 38:27-38. [PMID: 23817053 DOI: 10.1159/000353093] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 05/10/2013] [Indexed: 12/19/2022]
Abstract
BACKGROUND Membranous proliferative glomerulonephritis (MPGN) is a major primary cause of chronic kidney disease (CKD). Podocyte injury is crucial in the pathogenesis of glomerular disease with proteinuria, leading to CKD. To assess podocyte injuries in MPGN, the pathological features of spontaneous murine models were analyzed. METHODS The autoimmune-prone mice strains BXSB/MpJ-Yaa and B6.MRL-(D1Mit202-D1Mit403) were used as the MPGN models, and BXSB/MpJ-Yaa(+) and C57BL/6 were used as the respective controls. In addition to clinical parameters and glomerular histopathology, the protein and mRNA levels of podocyte functional markers were evaluated as indices for podocyte injuries. The relation between MPGN pathology and podocyte injuries was analyzed by statistical correlation. RESULTS Both models developed MPGN with albuminuria and elevated serum anti-double-strand DNA (dsDNA) antibody levels. BXSB/MpJ-Yaa and B6.MRL showed severe proliferative lesions with T and B cell infiltrations and membranous lesions with T cell infiltrations, respectively. Foot process effacement and microvillus-like structure formation were observed ultrastructurally in the podocytes of both MPGN models. Furthermore, both MPGN models showed a decrease in immune-positive areas of nephrin, podocin and synaptopodin in the glomerulus, and in the mRNA expression of Nphs1, Nphs2, Synpo, Actn4, Cd2ap, and Podxl in the isolated glomerulus. Significant negative correlations were detected between serum anti-dsDNA antibody levels and glomerular Nphs1 expression, and between urinary albumin-to-creatinine ratio and glomerular expression of Nphs1, Synpo, Actn4, Cd2ap, or Podxl. CONCLUSION MPGN models clearly developed podocyte injuries characterized by the decreased expression of podocyte functional markers with altered morphology. These data emphasized the importance of regulation of podocyte injuries in MPGN.
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Affiliation(s)
- Junpei Kimura
- Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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Terry SJ, Elbediwy A, Zihni C, Harris AR, Bailly M, Charras GT, Balda MS, Matter K. Stimulation of cortical myosin phosphorylation by p114RhoGEF drives cell migration and tumor cell invasion. PLoS One 2012; 7:e50188. [PMID: 23185572 PMCID: PMC3501466 DOI: 10.1371/journal.pone.0050188] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 10/19/2012] [Indexed: 12/31/2022] Open
Abstract
Actinomyosin activity is an important driver of cell locomotion and has been shown to promote collective cell migration of epithelial sheets as well as single cell migration and tumor cell invasion. However, the molecular mechanisms underlying activation of cortical myosin to stimulate single cell movement, and the relationship between the mechanisms that drive single cell locomotion and those that mediate collective cell migration of epithelial sheets are incompletely understood. Here, we demonstrate that p114RhoGEF, an activator of RhoA that associates with non-muscle myosin IIA, regulates collective cell migration of epithelial sheets and tumor cell invasion. Depletion of p114RhoGEF resulted in specific spatial inhibition of myosin activation at cell-cell contacts in migrating epithelial sheets and the cortex of migrating single cells, but only affected double and not single phosphorylation of myosin light chain. In agreement, overall elasticity and contractility of the cells, processes that rely on persistent and more constant forces, were not affected, suggesting that p114RhoGEF mediates process-specific myosin activation. Locomotion was p114RhoGEF-dependent on Matrigel, which favors more roundish cells and amoeboid-like actinomyosin-driven movement, but not on fibronectin, which stimulates flatter cells and lamellipodia-driven, mesenchymal-like migration. Accordingly, depletion of p114RhoGEF led to reduced RhoA, but increased Rac activity. Invasion of 3D matrices was p114RhoGEF-dependent under conditions that do not require metalloproteinase activity, supporting a role of p114RhoGEF in myosin-dependent, amoeboid-like locomotion. Our data demonstrate that p114RhoGEF drives cortical myosin activation by stimulating myosin light chain double phosphorylation and, thereby, collective cell migration of epithelial sheets and amoeboid-like motility of tumor cells.
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Affiliation(s)
- Stephen J. Terry
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ahmed Elbediwy
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ceniz Zihni
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Andrew R. Harris
- London Centre for Nanotechnology, University College London, London, United Kingdom
- Department of Physics and Doctorate Program of Engineering of the Department of Chemistry, University College London, London, United Kingdom
| | - Maryse Bailly
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Guillaume T. Charras
- London Centre for Nanotechnology, University College London, London, United Kingdom
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Maria S. Balda
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Karl Matter
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
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21
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Kunishima S, Tomii T, Kudo K, Saito H. G to T transversion at the first nucleotide of exon 26 of the MYH9 gene results in a novel missense mutation and abnormal splicing in platelets: comment on "A G to C transversion at the last nucleotide of exon 25 of the MYH9 gene results in a missense mutation rather than in a splicing defecton" by Vettore et al. Eur J Med Genet 2012; 55:763-5. [PMID: 22982478 DOI: 10.1016/j.ejmg.2012.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 09/03/2012] [Indexed: 11/27/2022]
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22
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Abstract
Members of the nonmuscle myosin-2 (NM-2) family of actin-based molecular motors catalyze the conversion of chemical energy into directed movement and force thereby acting as central regulatory components of the eukaryotic cytoskeleton. By cyclically interacting with adenosine triphosphate and F-actin, NM-2 isoforms promote cytoskeletal force generation in established cellular processes like cell migration, shape changes, adhesion dynamics, endo- and exo-cytosis, and cytokinesis. Novel functions of the NM-2 family members in autophagy and viral infection are emerging, making NM-2 isoforms regulators of nearly all cellular processes that require the spatiotemporal organization of cytoskeletal scaffolding. Here, we assess current views about the role of NM-2 isoforms in these activities including the tight regulation of NM-2 assembly and activation through phosphorylation and how NM-2-mediated changes in cytoskeletal dynamics and mechanics affect cell physiological functions in health and disease.
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Affiliation(s)
- Sarah M. Heissler
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Dietmar J. Manstein
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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23
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Eckly A, Rinckel JY, Laeuffer P, Cazenave JP, Lanza F, Gachet C, Léon C. Proplatelet formation deficit and megakaryocyte death contribute to thrombocytopenia in Myh9 knockout mice. J Thromb Haemost 2010; 8:2243-51. [PMID: 20695978 DOI: 10.1111/j.1538-7836.2010.04009.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Inactivation of the mouse Myh9 gene (Myh9Δ) or its mutation in MYH9-related diseases leads to macrothrombocytopenia. Paradoxically, previous studies using in vitro differentiated megakaryocytes showed an increased capacity for proplatelet formation when myosin was absent or inhibited. METHODS To explore the origin of the thrombocytopenia induced by myosin deficiency, we studied proplatelet formation using bone marrow explants of wild-type (WT) and Myh9Δ mouse where megakaryocytes have matured in their native environment. RESULTS AND DISCUSSION A dramatic decrease in the number and complexity of proplatelets was observed in megakaryocytes from Myh9Δ mice, while inhibition of myosin activity by blebbistatin increased proplatelet formation from WT mature megakaryocytes. Moreover, Myh9Δ megakaryocytes had a smaller size than the WT cells. These data indicate that myosin deficiency acts negatively on proplatelet formation, probably by impairing in situ megakaryocyte maturation, while myosin activity is dispensable at the latest stage of proplatelet formation. In addition, ultrastructural examination of Myh9Δ bone marrow revealed an increased proportion of megakaryocytes exhibiting signs of non-apoptotic cell death as compared with the WT mice. CONCLUSION These data indicate that thrombocytopenia in Myh9Δ mice results from defective development of megakaryocyte size, impaired proplatelet formation and increased cell death.
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Affiliation(s)
- A Eckly
- UMR_S949 INSERM-Université de Strasbourg, Etablissement Français du Sang-Alsace, Strasbourg, France
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24
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Kalson NS, Holmes DF, Kapacee Z, Otermin I, Lu Y, Ennos RA, Canty-Laird EG, Kadler KE. An experimental model for studying the biomechanics of embryonic tendon: Evidence that the development of mechanical properties depends on the actinomyosin machinery. Matrix Biol 2010; 29:678-89. [PMID: 20736063 PMCID: PMC3611596 DOI: 10.1016/j.matbio.2010.08.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 07/27/2010] [Accepted: 08/17/2010] [Indexed: 02/03/2023]
Abstract
Tendons attach muscles to bone and thereby transmit tensile forces during joint movement. However, a detailed understanding of the mechanisms that establish the mechanical properties of tendon has remained elusive because of the practical difficulties of studying tissue mechanics in vivo. Here we have performed a study of tendon-like constructs made by culturing embryonic tendon cells in fixed-length fibrin gels. The constructs display mechanical properties (toe-linear-fail stress-strain curve, stiffness, ultimate tensile strength, and failure strain) as well as collagen fibril volume fraction and extracellular matrix (ECM)/cell ratio that are statistically similar to those of embryonic chick metatarsal tendons. The development of mechanical properties during time in culture was abolished when the constructs were treated separately with Triton X-100 (to solubilise membranes), cytochalasin (to disassemble the actin cytoskeleton) and blebbistatin (a small molecule inhibitor of non-muscle myosin II). Importantly, these treatments had no effect on the mechanical properties of the constructs that existed prior to treatment. Live-cell imaging and (14)C-proline metabolic labeling showed that blebbistatin inhibited the contraction of the constructs without affecting cell viability, procollagen synthesis, or conversion of procollagen to collagen. In conclusion, the mechanical properties per se of the tendon constructs are attributable to the ECM generated by the cells but the improvement of mechanical properties during time in culture was dependent on non-muscle myosin II-derived forces.
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Key Words
- cvf, cell volume fraction, the fraction of the construct occupied by cells
- ecm, extracellular matrix
- ecmt, embryonic chick metatarsal tendon
- em, electron microscopy
- facs, fluorescence activated cell sorting
- fvf, fibril volume fraction, the fraction of the construct occupied by collagen fibrils
- nmmii, non-muscle myosin ii
- pbs, phosphate buffered saline
- bio-artificial tendon
- collagen
- elasticity
- electron microscopy
- extracellular matrix
- myosin
- fibril
- fibrin
- tension
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Affiliation(s)
- Nicholas S. Kalson
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - David F. Holmes
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Zoher Kapacee
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Iker Otermin
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Yinhui Lu
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Roland A. Ennos
- Faculty of Life Sciences, University of Manchester, Stopford Building, Oxford Road, Manchester M13 9PT, UK
| | - Elizabeth G. Canty-Laird
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Karl E. Kadler
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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25
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Roca-Cusachs P, Gauthier NC, del Rio A, Sheetz MP. Clustering of alpha(5)beta(1) integrins determines adhesion strength whereas alpha(v)beta(3) and talin enable mechanotransduction. Proc Natl Acad Sci U S A 2009; 106:16245-50. [PMID: 19805288 PMCID: PMC2752568 DOI: 10.1073/pnas.0902818106] [Citation(s) in RCA: 313] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Indexed: 12/12/2022] Open
Abstract
A key molecular link between cells and the extracellular matrix is the binding between fibronectin and integrins alpha(5)beta(1) and alpha(v)beta(3). However, the roles of these different integrins in establishing adhesion remain unclear. We tested the adhesion strength of fibronectin-integrin-cytoskeleton linkages by applying physiological nanonewton forces to fibronectin-coated magnetic beads bound to cells. We report that the clustering of fibronectin domains within 40 nm led to integrin alpha(5)beta(1) recruitment, and increased the ability to sustain force by over six-fold. This force was supported by alpha(5)beta(1) integrin clusters. Importantly, we did not detect a role of either integrin alpha(v)beta(3) or talin 1 or 2 in maintaining adhesion strength. Instead, these molecules enabled the connection to the cytoskeleton and reinforcement in response to an applied force. Thus, high matrix forces are primarily supported by clustered alpha(5)beta(1) integrins, while less stable links to alpha(v)beta(3) integrins initiate mechanotransduction, resulting in reinforcement of integrin-cytoskeleton linkages through talin-dependent bonds.
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Affiliation(s)
- Pere Roca-Cusachs
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY 10027; and
- Institute for Bioengineering of Catalonia, c/Baldiri Reixac 10-12, 08028 Barcelona, Spain
| | - Nils C. Gauthier
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY 10027; and
| | - Armando del Rio
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY 10027; and
| | - Michael P. Sheetz
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY 10027; and
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26
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Kunishima S. [Autosomal dominant macrothrombocytopenia with leukocyte inclusion bodies and MYH9 disorders]. Rinsho Byori 2009; 57:365-370. [PMID: 19489439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
May-Hegglin anomaly (MHA) is the prototype of autosomal dominant macrothrombocytopenia with leukocyte inclusion bodies/MYH9 disorders that result from mutations in MYH9, the gene for nonmuscle myosin heavy chain-IIA (NMMHC-IIA). Others include Sebastian, Fechtner, and Epstein syndromes. A clear phenotype-genotype relationship has not been found; however, patients with an MYH9 head domain mutation tend to develop Alport manifestations more frequently than those with a rod domain mutation. Patients initially diagnosed with MHA and/or Sebastian syndrome can subsequently develop nephritis, deafness, and/or cataracts. Thus, the development of Alport manifestations should be monitored by careful follow-up.
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Affiliation(s)
- Shinji Kunishima
- Laboratory of Molecular Diagnosis, Department of Advanced Diagnosis, Clinical Research Center, National Hospital Organization Nagoya Medical Center, Nagoya 460-0001, Japan.
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27
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Taylor J, Chung KH, Figueroa C, Zurawski J, Dickson HM, Brace EJ, Avery AW, Turner DL, Vojtek AB. The scaffold protein POSH regulates axon outgrowth. Mol Biol Cell 2008; 19:5181-92. [PMID: 18829867 PMCID: PMC2592661 DOI: 10.1091/mbc.e08-02-0231] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 08/28/2008] [Accepted: 09/23/2008] [Indexed: 12/13/2022] Open
Abstract
How scaffold proteins integrate signaling pathways with cytoskeletal components to drive axon outgrowth is not well understood. We report here that the multidomain scaffold protein Plenty of SH3s (POSH) regulates axon outgrowth. Reduction of POSH function by RNA interference (RNAi) enhances axon outgrowth in differentiating mouse primary cortical neurons and in neurons derived from mouse P19 cells, suggesting POSH negatively regulates axon outgrowth. Complementation analysis reveals a requirement for the third Src homology (SH) 3 domain of POSH, and we find that the actomyosin regulatory protein Shroom3 interacts with this domain of POSH. Inhibition of Shroom3 expression by RNAi leads to increased process lengths, as observed for POSH RNAi, suggesting that POSH and Shroom function together to inhibit process outgrowth. Complementation analysis and interference of protein function by dominant-negative approaches suggest that Shroom3 recruits Rho kinase to inhibit process outgrowth. Furthermore, inhibition of myosin II function reverses the POSH or Shroom3 RNAi phenotype, indicating a role for myosin II regulation as a target of the POSH-Shroom complex. Collectively, these results suggest that the molecular scaffold protein POSH assembles an inhibitory complex that links to the actin-myosin network to regulate neuronal process outgrowth.
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Affiliation(s)
| | - Kwan-Ho Chung
- Program in Neuroscience, and
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109
| | | | | | | | | | | | - David L. Turner
- *Department of Biological Chemistry
- Program in Neuroscience, and
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109
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28
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Yang HY, Wang ZY, Cao LJ, Zhao XJ, Bai X, Ruan CG. [Expression and function of non-muscle myosin-IIA in Fechtner syndrome]. Zhongguo Shi Yan Xue Ye Xue Za Zhi 2008; 16:871-874. [PMID: 18718080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The study was purposed to investigate the expression and function of non-muscle myosin heavy chain-IIA (NMMHC-IIA) in Fechtner syndrome in order to explore the pathologic changes of kindy disease and the mechanism of granulocyte inclusion body formation. NMMHC-IIA levels in granulocytes were analyzed by Western-blot, the expressions of NMMHC-IIA, IIB in HEK-293 cells were detected by RT-PCR and were analyzed by co-immunoprecipitation. The results indicated that the IIA/beta-actin ratio for Fechtner syndrome granulocytes was (0.35 +/- 0.12), and obviously decreased as compared with that of normal control (0.87 +/- 0.18) (p < 0.01). The IIA and IIB expressed higher in HEK-293 cells. The interaction of IIA and IIB was confirmed by co-immunoprecipitation in HEK-293 cells. It is concluded that dominant-negative effect of NMMHC-IIA is involved in the formation of inclusion bodies. IIA and IIB show obvious interaction, IIB partly compensates the IIA defect derived from MYH9 mutations, and may delay or prevent the development of clinically relevant abnormalities.
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Affiliation(s)
- Hai-Yan Yang
- Ministry of Health, Jiangsu Institute of Hematology, The First Hospital of Suzhou University, Suzhou 215006, Jiagnsu Province, China
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29
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Holt JP, Bottomly K, Mooseker MS. Assessment of myosin II, Va, VI and VIIa loss of function on endocytosis and endocytic vesicle motility in bone marrow-derived dendritic cells. ACTA ACUST UNITED AC 2007; 64:756-66. [PMID: 17615572 DOI: 10.1002/cm.20220] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
An essential feature of dendritic cell immune surveillance is endocytic sampling of the environment for non-self antigens primarily via macropinocytosis and phagocytosis. The role of several members of the myosin family of actin based molecular motors in dendritic cell endocytosis and endocytic vesicle movement was assessed through analysis of dendritic cells derived from mice with functionally null myosin mutations. These include the dilute (myosin Va), Snell's waltzer (myosin VI) and shaker-1 (myosin VIIa) mouse lines. Non muscle myosin II function was assessed by treatment with the inhibitor, blebbistatin. Flow cytometric analysis of dextran uptake by dendritic cells revealed that macropinocytosis was enhanced in Snell's waltzer dendritic cells while shaker-1 and blebbistatin-treated cells were comparable to controls. Comparison of fluid phase uptake using pH insensitive versus pH sensitive fluorescent dextrans revealed that in dilute cells rates of uptake were normal but endosomal acidification was accelerated. Phagocytosis, as quantified by uptake of E. coli, was normal in dilute while dendritic cells from Snell's waltzer, shaker-1 and blebbistatin treated cells exhibited decreased uptake. Microtubule mediated movements of dextran-or transferrin-tagged endocytic vesicles were significantly faster in dendritic cells lacking myosin Va. Loss of myosin II, VI or VIIa function had no significant effects on rates of endocytic vesicle movement.
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Affiliation(s)
- Jeffrey P Holt
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, USA
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30
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Léon C, Eckly A, Hechler B, Aleil B, Freund M, Ravanat C, Jourdain M, Nonne C, Weber J, Tiedt R, Gratacap MP, Severin S, Cazenave JP, Lanza F, Skoda R, Gachet C. Megakaryocyte-restricted MYH9 inactivation dramatically affects hemostasis while preserving platelet aggregation and secretion. Blood 2007; 110:3183-91. [PMID: 17664350 DOI: 10.1182/blood-2007-03-080184] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
AbstractMutations in the MYH9 gene encoding the nonmuscle myosin heavy chain IIA result in bleeding disorders characterized by a macrothrombocytopenia. To understand the role of myosin in normal platelet functions and in pathology, we generated mice with disruption of MYH9 in megakaryocytes. MYH9Δ mice displayed macrothrombocytopenia with a strong increase in bleeding time and absence of clot retraction. However, platelet aggregation and secretion in response to any agonist were near normal despite absence of initial platelet contraction. By contrast, integrin outside-in signaling was impaired, as observed by a decrease in integrin β3 phosphorylation and PtdIns(3,4)P2 accumulation following stimulation. Upon adhesion on a fibrinogen-coated surface, MYH9Δ platelets were still able to extend lamellipodia but without stress fiber–like formation. As a consequence, thrombus growth and organization, investigated under flow by perfusing whole blood over collagen, were strongly impaired. Thrombus stability was also decreased in vivo in a model of FeCl3-induced injury of carotid arteries. Overall, these results demonstrate that while myosin seems dispensable for aggregation and secretion in suspension, it plays a key role in platelet contractile phenomena and outside-in signaling. These roles of myosin in platelet functions, in addition to thrombocytopenia, account for the strong hemostatic defects observed in MYH9Δ mice.
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Affiliation(s)
- Catherine Léon
- INSERM U311, Etablissement Français du Sang-Alsace, 10 rue Spielmann, 67065 Strasbourg Cedex, France.
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31
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Abstract
Natural killer (NK) cell cytotoxicity involves the formation of an activating immunological synapse (IS) between the effector and target cell through which granzymes and perforin contained in lytic granules are delivered to the target cell via exocytosis. Inhibition of nonmuscle myosin II in human NK cells with blebbistatin or ML-9 impaired neither effector–target cell conjugation nor formation of a mature activating NK cell IS (NKIS; formation of an actin ring and polarization of the microtubule-organizing center and cytolytic granules to the center of the ring). However, membrane fusion of lytic granules, granzyme secretion, and NK cell cytotoxicity were all effectively blocked. Specific knockdown of the myosin IIA heavy chain by RNA interference impaired cytotoxicity, membrane fusion of lytic granules, and granzyme secretion. Thus, myosin IIA is required for a critical step between NKIS formation and granule exocytosis.
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Affiliation(s)
- Milena M Andzelm
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
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32
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Mhatre AN, Li Y, Bhatia N, Wang KH, Atkin G, Lalwani AK. Generation and Characterization of Mice with Myh9 Deficiency. Neuromolecular Med 2007; 9:205-15. [PMID: 17914179 DOI: 10.1007/s12017-007-8008-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 01/13/2023]
Abstract
Mutant alleles of MYH9 encoding a class II non-muscle myosin heavy chain-A (NMMHC-IIA) have been linked to hereditary megathrombocytopenia with or without additional clinical features that include sensorineural deafness, cataracts, and nephritis. To assess its biological role in the affected targets, particularly the inner ear, we have generated and characterized mice with Myh9 deficiency. These mice were generated using the XA136 ES cell line (BayGenomics, http://baygenomics.ucsf.edu/) carrying gene trap insertion in Myh9, within the intron flanking exons 4 and 5. Mice heterozygous for the Myh9 null allele, Myh9 +/- were expanded on C57BL/6J background. Intercross of the Myh9 +/- mice did not yield Myh9 -/- pups, indicating embryonic lethality, subsequently determined to occur at or before E7.5, thus precluding a post-natal analysis of the effects of complete Myh9 deficiency. The heterozygous mice were normal for their hearing, parameters of platelet integrity and renal function despite their Myh9 haplo-insufficiency. In addition, the age-dependent auditory threshold of the Myh9 +/- mice and their wild type littermates, spanning from 3 to 12 months of age, were similar indicating that Myh9 haplo-insufficiency does not contribute towards accelerated age-related hearing loss (AHL). The embryonic lethality associated with the complete Myh9 deficiency establishes a critical role for this non-muscle myosin in fetal development. The results of these studies do not support the Myh9 haploinsufficiency as a pathogenic factor in the etiology of auditory dysfunction.
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Affiliation(s)
- Anand N Mhatre
- Laboratory of Molecular Genetics, Department of Otolaryngology, New York University School of Medicine, 560 First Ave, TCH 513, New York, NY 10016, USA.
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33
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Chen Z, Naveiras O, Balduini A, Mammoto A, Conti MA, Adelstein RS, Ingber D, Daley GQ, Shivdasani RA. The May-Hegglin anomaly gene MYH9 is a negative regulator of platelet biogenesis modulated by the Rho-ROCK pathway. Blood 2007; 110:171-9. [PMID: 17392504 PMCID: PMC1896110 DOI: 10.1182/blood-2007-02-071589] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The gene implicated in the May-Hegglin anomaly and related macrothrombocytopenias, MYH9, encodes myosin-IIA, a protein that enables morphogenesis in diverse cell types. Defective myosin-IIA complexes are presumed to perturb megakaryocyte (MK) differentiation or generation of proplatelets. We observed that Myh9(-/-) mouse embryonic stem (ES) cells differentiate into MKs that are fully capable of proplatelet formation (PPF). In contrast, elevation of myosin-IIA activity, by exogenous expression or by mimicking constitutive phosphorylation of its regulatory myosin light chain (MLC), significantly attenuates PPF. This effect occurs only in the presence of myosin-IIA and implies that myosin-IIA influences thrombopoiesis negatively. MLC phosphorylation in MKs is regulated by Rho-associated kinase (ROCK), and consistent with our model, ROCK inhibition enhances PPF. Conversely, expression of AV14, a constitutive form of the ROCK activator Rho, blocks PPF, and this effect is rescued by simultaneous expression of a dominant inhibitory MLC form. Hematopoietic transplantation studies in mice confirm that interference with the putative Rho-ROCK-myosin-IIA pathway selectively decreases the number of circulating platelets. Our studies unveil a key regulatory pathway for platelet biogenesis and hint at Sdf-1/CXCL12 as one possible extracellular mediator. The unexpected mechanism for Myh9-associated thrombocytopenia may lead to new molecular approaches to manipulate thrombopoiesis.
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Affiliation(s)
- Zhao Chen
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
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34
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Martinelli M, Di Stazio M, Scapoli L, Marchesini J, Di Bari F, Pezzetti F, Carinci F, Palmieri A, Carinci P, Savoia A. Cleft lip with or without cleft palate: implication of the heavy chain of non-muscle myosin IIA. J Med Genet 2007; 44:387-92. [PMID: 17337617 PMCID: PMC2740885 DOI: 10.1136/jmg.2006.047837] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Non-syndromic cleft lip with or without palate (CL/P) is one of the most common malformations among live births, but most of the genetic components and environmental factors involved remain to be identified. Among the different causes, MYH9, the gene encoding for the heavy chain of non-muscle myosin IIA, was considered a potential candidate, because it was found to be abundantly and specifically expressed in epithelial cells of palatal shelves before fusion. After fusion, its expression level was shown to decrease and to become limited to epithelial triangles before disappearing, as fusion is completed. To determine whether MYH9 plays a role in CL/P aetiology, a family-based association analysis was performed in 218 case/parent triads using single-nucleotide polymorphism (SNP) markers. Pairwise and multilocus haplotype analyses identified linkage disequilibrium between polymorphism alleles at the MYH9 locus and the disease. The strongest deviation from a null hypothesis of random sharing was obtained with two adjacent SNPs, rs3752462 and rs2009930 (global p value = 0.001), indicating that MYH9 might be a predisposing factor for CL/P, although its pathogenetic role needs to be investigated more accurately.
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35
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Rey M, Valenzuela-Fernández A, Urzainqui A, Yáñez-Mó M, Pérez-Martínez M, Penela P, Mayor F, Sánchez-Madrid F. Myosin IIA is involved in the endocytosis of CXCR4 induced by SDF-1alpha. J Cell Sci 2007; 120:1126-33. [PMID: 17327270 DOI: 10.1242/jcs.03415] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Endocytosis of chemokine receptors regulates signal transduction initiated by chemokines, but the molecular mechanisms underlying this process are not fully defined. In this work, we assessed the involvement of the motor protein nonmuscle myosin heavy chain IIA (MIIA) in the endocytosis of CXCR4 induced by SDF-1alpha (also known as CXCL12) in T lymphocytes. Overexpression of the C-terminal half of MIIA inhibited the ligand-induced endocytosis of CXCR4, but not that of transferrin receptor. Targeting MIIA either by silencing its expression with small interfering RNA (siRNA) or by blebbistatin treatment also inhibited endocytosis of CXCR4. Inhibition of endocytosis of CXCR4 by targeting endogenous MIIA resulted in an increased migration of T cells induced by SDF-1alpha, and in the inhibition of the HIV-1-Env antifusogenic activity of this chemokine. Coimmunoprecipitation and protein-protein binding studies demonstrated that MIIA interacts with both the cytoplasmic tail of CXCR4 and beta-arrestin. Moreover, SDF-1alpha promotes a rapid MIIA-beta-arrestin dissociation. Our data reveal a novel role for MIIA in CXCR4 endocytosis, which involves its dynamic association with beta-arrestin and highlights the role of endogenous MIIA as a regulator of CXCR4 internalization and, therefore, the onset of SDF-1alpha signaling.
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Affiliation(s)
- Mercedes Rey
- Servicio de Inmunología, Hospital Universitario de la Princesa, Diego de León, 62, 28006 Madrid, Spain
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Even-Ram S, Doyle AD, Conti MA, Matsumoto K, Adelstein RS, Yamada KM. Myosin IIA regulates cell motility and actomyosin–microtubule crosstalk. Nat Cell Biol 2007; 9:299-309. [PMID: 17310241 DOI: 10.1038/ncb1540] [Citation(s) in RCA: 404] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Accepted: 01/17/2007] [Indexed: 01/27/2023]
Abstract
Non-muscle myosin II has diverse functions in cell contractility, cytokinesis and locomotion, but the specific contributions of its different isoforms have yet to be clarified. Here, we report that ablation of the myosin IIA isoform results in pronounced defects in cellular contractility, focal adhesions, actin stress fibre organization and tail retraction. Nevertheless, myosin IIA-deficient cells display substantially increased cell migration and exaggerated membrane ruffling, which was dependent on the small G-protein Rac1, its activator Tiam1 and the microtubule moter kinesin Eg5. Myosin IIA deficiency stabilized microtubules, shifting the balance between actomyosin and microtubules with increased microtubules in active membrane ruffles. When microtubule polymerization was suppressed, myosin IIB could partially compensate for the absence of the IIA isoform in cellular contractility, but not in cell migration. We conclude that myosin IIA negatively regulates cell migration and suggest that it maintains a balance between the actomyosin and microtubule systems by regulating microtubule dynamics.
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Affiliation(s)
- Sharona Even-Ram
- Craniofacial Developmental Biology and Regeneration Branch, National Institute of Dental and Craniofacial Research (NIDCR), National Institutes of Health, Bethesda, MD 20892, USA
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Swailes NT, Colegrave M, Knight PJ, Peckham M. Non-muscle myosins 2A and 2B drive changes in cell morphology that occur as myoblasts align and fuse. J Cell Sci 2006; 119:3561-70. [PMID: 16895968 DOI: 10.1242/jcs.03096] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The interaction of non-muscle myosins 2A and 2B with actin may drive changes in cell movement, shape and adhesion. To investigate this, we used cultured myoblasts as a model system. These cells characteristically change shape from triangular to bipolar when they form groups of aligned cells. Antisense oligonucleotide knockdown of non-muscle myosin 2A, but not non-muscle myosin 2B, inhibited this shape change, interfered with cell-cell adhesion, had a minor effect on tail retraction and prevented myoblast fusion. By contrast, non-muscle myosin 2B knockdown markedly inhibited tail retraction, increasing cell length by over 200% by 72 hours compared with controls. In addition it interfered with nuclei redistribution in myotubes. Non-muscle myosin 2C is not involved as western analysis showed that it is not expressed in myoblasts, but only in myotubes. To understand why non-muscle myosins 2A and 2B have such different roles, we analysed their distributions by immuno-electron microscopy, and found that non-muscle myosin 2A was more tightly associated with the plasma membrane than non-muscle myosin 2B. This suggests that non-muscle myosin 2A is more important for bipolar shape formation and adhesion owing to its preferential interaction with membrane-associated actin, whereas the role of non-muscle myosin 2B in retraction prevents over-elongation of myoblasts.
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Affiliation(s)
- Nathan T Swailes
- Institute of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
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Abstract
Initial stages of tumor cell metastasis involve an epithelial-mesenchyme transition that involves activation of amoeboid migration and loss of cell-cell adhesion. The actomyosin cytoskeleton has fundamental but poorly understood roles in these events. Myosin II, an abundant force-producing protein, has roles in cell body translocation and retraction of the posterior of the cell during migration. Recent studies have suggested that this protein may also have roles in leading edge protrusive events. The metastasis-promoting protein metastasin-1, a regulator of myosin II assembly, colocalizes with myosin IIA at the leading edge of cancer cells, suggesting direct roles for myosin II in metastatic behavior. We have assessed the roles of specific myosin II isoforms during lamellar spreading of MDA-MB-231 breast cancer cells on extracellular matrix. We find that the two major myosin II isoforms IIA and IIB are both expressed in these cells, and both are recruited dramatically to the lamellar margin during active spreading on fibronectin. There is also a transient increase in regulatory light chain phosphorylation that correlates the recruitment of myosin IIA and myosin IIB into this spreading margin. Pharmacologic inhibition of myosin II or myosin light chain kinase dramatically reduced spreading. Depletion of myosin IIA via small interfering RNA impaired migration but enhanced lamellar spreading, whereas depletion of myosin IIB impaired not only migration but also impaired initial rates of lamellar spreading. These results indicate that both isoforms are critical for the mechanics of cell migration, with myosin IIB seeming to have a preferential role in the mechanics of lamellar protrusion.
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Affiliation(s)
- Venkaiah Betapudi
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Marini M, Bruschi M, Pecci A, Romagnoli R, Musante L, Candiano G, Ghiggeri GM, Balduini C, Seri M, Ravazzolo R. Non-muscle myosin heavy chain IIA and IIB interact and co-localize in living cells: relevance for MYH9-related disease. Int J Mol Med 2006; 17:729-36. [PMID: 16596254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
Abstract
Myosins of class II constitute part of a superfamily of several classes of proteins expressed in almost all eukaryotic cell types. Differences in the heavy chains produce three isoforms of class II non-muscle myosins (A, B and C), which are widely distributed in most tissues and thought to be components of the cell motor systems, although specific functional roles are largely unknown. In particular, it is still a matter of debate whether they interact and have overlapping or distinct functions. This argument is relevant not only to cell physiology, but also to human pathology since mutations of the MYH9 gene encoding non-muscle myosin heavy chain II A (NMMHC-A) cause MYH9-related disease (MYH9-RD), an autosomal dominant disorder characterized by platelet macrocytosis, thrombocytopenia and leukocyte inclusions, variably associated with sensorineural hearing loss, cataracts and/or glomerulonephritis. In this study, we report the results of yeast two-hybrid screening showing that the C-terminals of NMMHC-A and -B interact. This interaction was confirmed by immunoprecipitation in transfected COS-7 cells and in skin fibroblasts naturally expressing both isoforms. Moreover, our immunomorphological study revealed that isoforms A and B co-localize in fibroblasts, erythroblasts and kidney cells. These results suggest that isoforms A and B are strictly related molecules and support the hypothesis that their interrelationship could be involved both in the variability of clinical phenotype and selectivity of tissue damage of MYH9-RD.
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Affiliation(s)
- Monica Marini
- Laboratory of Molecular Genetics, G. Gaslini Institute, 16147 Genova, Italy
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40
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Reville K, Crean JK, Vivers S, Dransfield I, Godson C. Lipoxin A4 Redistributes Myosin IIA and Cdc42 in Macrophages: Implications for Phagocytosis of Apoptotic Leukocytes. J Immunol 2006; 176:1878-88. [PMID: 16424219 DOI: 10.4049/jimmunol.176.3.1878] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Lipoxins (LXs) are endogenously produced anti-inflammatory agents that modulate leukocyte trafficking and stimulate nonphlogistic macrophage phagocytosis of apoptotic neutrophils, thereby promoting the resolution of inflammation. Previous data suggest a role for altered protein phosphorylation and cytoskeletal rearrangement in LX-stimulated phagocytosis but the exact mechanisms remain unclear. In this study we examine the effects of LXA4 on the protein phosphorylation pattern of THP-1 cells differentiated into a macrophage-like phenotype. THP-1 cells stimulated with LXA4 (1 nM) exhibit dephosphorylation of a 220-kDa protein. Using mass spectrometry, this protein was identified as MYH9, a nonmuscle myosin H chain II isoform A, which is involved in cytoskeleton rearrangement. THP-1 cells treated with LXA4 adopt a polarized morphology with activated Cdc42 localized toward the leading edge and MYH9 localized at the cell posterior. Polarized distribution of Cdc42 is associated with Akt/PKB-mediated Cdc42 activation. Interestingly, the annexin-derived peptide Ac2-26, a recently described agonist for the LXA4 receptor, also stimulates macrophage phagocytosis, MYH9 dephosphorylation, and MYH9 redistribution. In addition, we demonstrate that LXA4 stimulates the phosphorylation of key polarity organization molecules: Akt, protein kinase Czeta, and glycogen synthase kinase-3beta. Inhibition of LXA4-induced Akt and protein kinase Czeta activity with specific inhibitors prevented LXA4-stimulated phagocytosis of both apoptotic polymorphonuclear neutrophils and lymphocytes, highlighting a potential use for LXA4 in the treatment of autoimmune diseases. Furthermore, phosphorylation and subsequent inactivation of glycogen synthase kinase-3beta resulted in an increase in phagocytosis similar to that of LXA4. These data highlight an integrated mechanism whereby LXA4 regulates phagocytosis through facilitative actin cytoskeleton rearrangement and cell polarization.
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Affiliation(s)
- Keira Reville
- School of Medicine and Medical Sciences, Conway Institute, University College Dublin, Belfield, Ireland
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41
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Abstract
Mutations of non-muscle myosin Type IIA or MYH9 are linked to syndromic or nonsyndromic hearing loss. The biologic function of MYH9 in the auditory organ and the pathophysiology of its dysfunction remain to be determined. The mouse represents an excellent model for investigating the biologic role of MYH9 in the cells and tissues affected by its dysfunction. A primary step toward the understanding of the role of MYH9 in hearing and its dysfunction is the documentation of its cellular and sub-cellular localization within the cochlea, the auditory organ. We describe the localization of Myh9 within the mouse cochlea using a polyclonal anti-Myh9-antibody, generated against an 18 amino acid long peptide corresponding to the sequence at the C-terminus of mouse Myh9. The anti-Myh9 antibody identified a single, specific, immunoreactive band of 220 kDa in immunoblot analysis of homogenate from a variety of different mouse tissues. The Myh9 antibody cross-reacts with the rat but not the human orthologue. Myh9 is expressed predominantly within the spiral ligament as well as in the sensory hair cells of the organ of Corti. Confocal microscopy of cochlear surface preparations, identified Myh9 within the inner and outer hair cells and their stereocilia. Localization of Myh9 within the stereocilia raises the possibility that mutations of MYH9 may effect hearing loss though disruption of the stereocilia structure.
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Affiliation(s)
- Anand N Mhatre
- Laboratory of Molecular Otology, Department of Otolaryngology, New York University School of Medicine, New York, New York 10016, USA.
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Zhang M, Rao PV. Blebbistatin, a novel inhibitor of myosin II ATPase activity, increases aqueous humor outflow facility in perfused enucleated porcine eyes. Invest Ophthalmol Vis Sci 2005; 46:4130-8. [PMID: 16249490 DOI: 10.1167/iovs.05-0164] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To investigate the specific role of myosin II, a critical biochemical determinant of cellular contraction, in modulation of aqueous humor outflow facility through the trabecular meshwork (TM) pathway. METHODS Expression of the nonmuscle myosin II heavy chains (IIA, IIB, and IIC) in human TM and ciliary body (CB) cells was determined by RT-PCR analyses. The effects of inhibition of myosin II on cell morphology, actomyosin organization, and cell adhesions were evaluated in porcine TM and CB cells treated with blebbistatin, a cell-permeable, specific inhibitor of myosin II adenosine triphosphatase (ATPase) activity. Changes in aqueous humor outflow facility were determined in enucleated porcine eyes by using a constant-pressure Grant perfusion model system. Ultrastructural integrity of the outflow pathway in drug-perfused eyes was analyzed by transmission electron microscopy. RESULTS Expression of nonmuscle myosin IIA and IIB was confirmed in both human TM and CB cells. Confluent cultures of primary porcine TM and CB cells treated with blebbistatin in the presence of serum revealed dose (10-200 microM)-dependent changes in cell morphology, decreases in actin stress fiber content and in focal adhesions and adherens junctions. These changes were found to be reversible within 24 hours of drug withdrawal from the cell culture media. Blebbistatin did not affect the status of myosin light chain phosphorylation in TM cells. Perfusion of enucleated porcine eyes for 5 hours with 100 and 200 microM blebbistatin produced a significant increase (P < 0.01, n = 7) in aqueous outflow facility (53% and 64%, respectively) from the baseline facility, compared with a 21% facility increase in sham control specimens. The integrity of the inner wall of aqueous plexi in drug-perfused porcine eyes was found to be intact, and TM cell morphology appeared to be similar to that noted in sham-treated eyes. CONCLUSIONS These data demonstrate that selective inhibition of myosin II in the aqueous humor outflow pathway leads to increased aqueous outflow facility, suggesting a critical role for myosin II in the regulation of aqueous humor outflow facility. This study also suggests myosin II as a potential therapeutic target for lowering intraocular pressure in patients with glaucoma.
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Affiliation(s)
- Min Zhang
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA
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Green JL, Martin SR, Fielden J, Ksagoni A, Grainger M, Yim Lim BYS, Molloy JE, Holder AA. The MTIP-myosin A complex in blood stage malaria parasites. J Mol Biol 2005; 355:933-41. [PMID: 16337961 DOI: 10.1016/j.jmb.2005.11.027] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2005] [Revised: 11/04/2005] [Accepted: 11/09/2005] [Indexed: 10/25/2022]
Abstract
Parasites of the Apicomplexa phylum use an actomyosin motor to drive invasion of host cells. The motor complex is located at the parasite's periphery between the plasma membrane and an inner membrane complex. A crucial component of this complex is myosin tail domain interacting protein (MTIP) identified in the murine malaria parasite Plasmodium yoelii. Here, we show that MTIP is expressed in Plasmodium falciparum merozoites, localises to the periphery of the cell and is present in a complex with myosin A. The MTIP-myosin A tail interaction has a Kd of 235 nM and calcium ions do not play a role in modulating the binding affinity of the two molecules, despite reports of a predicted EF-hand in MTIP. Antibodies to MTIP were used to immobilise the MTIP-myosin A complex, allowing actin binding and motility to be examined. Measurement of actin filament velocities powered by myosin A revealed a velocity of 3.51 microm s(-1), a speed comparable to fast muscle myosins. A short peptide derived from the tail of myosin A (C-MyoA) bound to MTIP and was able to disrupt the association of MTIP and myosin A in parasite lysates. C-MyoA peptidomimetic compounds that disrupt the MTIP-myosin A interaction are predicted to inhibit parasite motility and host cell invasion, which may be targets for new therapeutic approaches.
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Affiliation(s)
- Judith L Green
- Division of Parasitology, MRC National Institute for Medical Research, London NW7 1AA, UK.
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Bao J, Jana SS, Adelstein RS. Vertebrate nonmuscle myosin II isoforms rescue small interfering RNA-induced defects in COS-7 cell cytokinesis. J Biol Chem 2005; 280:19594-9. [PMID: 15774463 DOI: 10.1074/jbc.m501573200] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RNA interference (RNAi) treatment of monkey COS-7 cells, a cell line that lacks nonmuscle myosin heavy chain II-A (NMHC II-A) but contains NMHC II-B and II-C, was used to investigate the participation of NMHC isoforms in cytokinesis. We specifically suppressed the expression of NMHC II-B or II-C using 21 nucleotide small interfering RNA (siRNA) duplexes. Down-regulation of NMHC II-B protein expression to 10.2 +/- 0.7% inhibited COS-7 cell proliferation by 50% in the RNAi-treated cells compared with control cells. Moreover, whereas 8.7 +/- 1.0% of control cells were multinucleated, 62.4 +/- 8.8% of the NMHC II-B RNAi-treated cells were multinucleated 72 h after transfection. The RNAi-treated cells had increased surface areas and, unlike control cells, lacked actin stress fibers. Treatment of the COS-7 cells with NMHC II-C siRNA decreased NMHC II-C expression to 5.2 +/- 0.1% compared with the endogenous content of II-C; however, down-regulation of NMHC II-C did not cause increased multinucleation. Immunoblot analysis using a pan-myosin antibody showed that the content of NMHC II-C was less than one-twentieth the amount of NMHC II-B, thereby explaining the lack of response to II-C siRNA. Introducing green fluorescent protein (GFP)-tagged NMHC II isoforms into II-B siRNA-treated cells resulted in reduction of multinucleation from 62.4 +/- 8.8% to 17.8 +/- 2.2% using GFP-NMHC II-B, to 29.8 +/- 7.4% using GFP-NMHC II-A, and to 34.1 +/- 8.6% using NMHC II-C-GFP. These studies have shown that expression of endogenous NMHC II-C in COS-7 cells is insufficient for normal cytokinesis and that exogenous NMHC II-A and NMHC II-C can, at least partially, rescue the defect in cytokinesis due to the loss of NMHC II-B.
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Affiliation(s)
- Jianjun Bao
- Laboratory of Molecular Cardiology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA
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45
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Conti MA, Even-Ram S, Liu C, Yamada KM, Adelstein RS. Defects in cell adhesion and the visceral endoderm following ablation of nonmuscle myosin heavy chain II-A in mice. J Biol Chem 2004; 279:41263-6. [PMID: 15292239 DOI: 10.1074/jbc.c400352200] [Citation(s) in RCA: 261] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previous work has shown that ablation or mutation of nonmuscle myosin heavy chain II-B (NMHC II-B) in mice results in defects in the heart and brain with death occurring between embryonic day 14.5 (E14.5) and birth (Tullio, A. N., Accili, D., Ferrans, V. J., Yu, Z. X., Takeda, K., Grinberg, A., Westphal, H., Preston, Y. A., and Adelstein, R. S. (1997) Proc. Natl. Acad. Sci. U. S. A. 94, 12407-12412). Here we show that mice ablated for NMHC II-A fail to develop a normal patterned embryo with a polarized visceral endoderm by E6.5 and die by E7.5. Moreover, A(-)/A(-) embryoid bodies grown in suspension culture constantly shed cells. These defects in cell adhesion and tissue organization are explained by loss of E-cadherin and beta-catenin localization to cell adhesion sites in both cell culture and in the intact embryos. The defects can be reproduced by introducing siRNA directed against NMHC II-A into wild-type embryonic stem cells. Our results suggest an essential role for a single, specific nonmuscle myosin isoform in maintaining cell-cell adhesions in the early mammalian embryo.
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Affiliation(s)
- Mary Anne Conti
- Laboratory of Molecular Cardiology, NHLBI, National Institutes of Health, Bethesda, MD 20892, USA.
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Abstract
OBJECTIVE To evaluate muscle performance and its consequences in eight individuals with a hereditary myopathy and the effects of an 8-week endurance training program. MATERIAL AND METHODS Handgrip, muscle strength and endurance and oxygen consumption by breath-by-breath analysis during a stepless bicycle ergonometer test were evaluated. Walking, balance test and activities of daily living (ADL) were assessed, and a questionnaire for activity level and perceived symptoms was used. The design was a before-after trial in comparison with data from a control population, bicycling at 70% of maximal workload, 30 min/day, 5 days/week for 8 weeks. RESULTS The subjects were weaker than age-matched controls. After training, the peak watt increased by almost 20% (P < 0.05). Muscle strength (flexion/extension) and isometric endurance (40% of maximum at 60 degrees ) did not change significantly. The average self-selected walking speed increased significantly (P < 0.05) from 1.25 to 1.45 m/s. Compliance was excellent and no serious adverse events occurred. CONCLUSION Endurance training seems to function for this myopathy.
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Affiliation(s)
- K S Sunnerhagen
- Department of Clinical Neuroscience-Rehabilitation Medicine, Sahlgrenska Academy, Göteborg University, Göteborg, Sweden.
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Pujol-Moix N, Kelley MJ, Hernández A, Muñiz-Diaz E, Español I. Ultrastructural analysis of granulocyte inclusions in genetically confirmed MYH9-related disorders. Haematologica 2004; 89:330-7. [PMID: 15020273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
BACKGROUND AND OBJECTIVES MYH9-related disorders are autosomal dominant hereditary macrothrombocytopenias caused by mutations in the MYH9 gene. This gene encodes the non-muscular myosin heavy chain type II A (MHCIIA). Among these disorders, May-Hegglin anomaly (MHA), Sebastian syndrome (SS), and Fechtner syndrome (FS) are associated with different types of ribosome inclusions in granulocytes. FS also exhibits Alport-like manifestations: nephropathy, neurosensory deafness, and cataracts. The aim of our study was to assess the granulocyte inclusion ultrastructure in genetically confirmed MYH9-related disorders. DESIGN AND METHODS Ten individuals were studied. All fulfilled the clinical and laboratory findings to be diagnosed as having an MYH9-related disorder. The ultrastructure of 50 granulocyte sections for each patient was examined, and the percentages of the different types of inclusion were established. Mutations of the MYH9 gene were also analyzed. RESULTS The patients were classified as having MHA if the inclusions contained parallel longitudinal filaments. If not, they were classified as having SS or FS. FS patients also showed Alport-like manifestations. In all syndromes we observed a wide variability of the inclusion ultrastructure. Moreover, a small number of inclusions typical of other syndromes was observed. A new cross-striated inclusion variant was identified in SS. A significant number of pure ribosome aggregates were identified in all syndromes. INTERPRETATION AND CONCLUSIONS Like other MYH9-related traits, the variation and partial overlap in the inclusion ultrastructure could be attributed to specific changes in the polymerization, assembly, or stability of the MHCIIA. These changes might be associated with MYH9 gene mutations as well as with its heterogeneous expression.
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Affiliation(s)
- Núria Pujol-Moix
- Departament d'Hematologia, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
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Mhatre AN, Li J, Kim Y, Coling DE, Lalwani AK. Cloning and developmental expression of nonmuscle myosin IIA (Myh9) in the mammalian inner ear. J Neurosci Res 2004; 76:296-305. [PMID: 15079858 DOI: 10.1002/jnr.20065] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
MYH9 encoding a nonmuscle myosin heavy chain has been linked to nonsyndromic and syndromic forms of autosomal dominant hereditary hearing loss, suggesting a critical biological role of this motor protein in the auditory organ. While Myh9 expression has been described in the adult mouse, critical parameters pertaining to its developmental expression remain to be characterized. The current study describes cloning of the mouse Myh9 cDNA and the temporal onset and spatial distribution of Myh9 expression in the inner ear of the developing fetus, the neonate, and the adult. The cloned Myh9 cDNA contained two single-base-pair differences from the published genomic sequence: T990C (G330G) and T5198A (L1733Q). Immunoblotting of embryonic (E15.5) and adult tissues from several organs, including the cochlea, identified a single 250-kDa anti-Myh9-immunoreactive band, supporting an absence of Myh9 splice variants in the fetus and the adult. In situ expression analysis identified Myh9 distributed within the epithelial layer of the otic vesicle at E10.5. Myh9 expression was found to persist within the epithelia surrounding the cochlear duct at E13.5 and E16.5. The sensory cells of the developing cochlea were positive for Myh9 expression at E16.5. Within the neonate and the adult cochlea, Myh9 expression was observed within the sensory hair cells and the supporting hair cells of the organ of Corti, the spiral ligament, and the spiral limbus, but not in the stria vascularis. Identification of Myh9 in the developing and mature inner ear suggests a role for this protein in the development and maintenance of auditory function.
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Affiliation(s)
- Anand N Mhatre
- Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
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49
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Ozaslan D, Wang S, Ahmed BA, Kocabas AM, McCastlain JC, Bene A, Kilic F. Glycosyl modification facilitates homo- and hetero-oligomerization of the serotonin transporter. A specific role for sialic acid residues. J Biol Chem 2003; 278:43991-4000. [PMID: 12944413 PMCID: PMC3042025 DOI: 10.1074/jbc.m306360200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The serotonin transporter (SERT) is an oligomeric glycoprotein with two sialic acid residues on each of two complex oligosaccharide molecules. In this study, we investigated the contribution of N-glycosyl modification to the structure and function of SERT in two model systems: wild-type SERT expressed in sialic acid-defective Lec4 Chinese hamster ovary (CHO) cells and a mutant form (after site-directed mutagenesis of Asn-208 and Asn-217 to Gln) of SERT, QQ, expressed in parental CHO cells. In both systems, SERT monomers required modification with both complex oligosaccharide residues to associate with each other and to function in homo-oligomeric forms. However, defects in sialylated N-glycans did not alter surface expression of the SERT protein. Furthermore, in heterologous (CHO and Lec4 cells) and endogenous (placental choriocarcinoma JAR cells) expression systems, we tested whether glycosyl modification also manipulates the hetero-oligomeric interactions of SERT, specifically with myosin IIA. SERT is phosphorylated by cGMP-dependent protein kinase G through interactions with anchoring proteins, and myosin is a protein kinase G-anchoring protein. A physical interaction between myosin and SERT was apparent; however, defects in sialylated N-glycans impaired association of SERT with myosin as well as the stimulation of the serotonin uptake function in the cGMP-dependent pathway. We propose that sialylated N-glycans provide a favorable conformation to SERT that allows the transporter to function most efficiently via its protein-protein interactions.
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Affiliation(s)
| | | | | | | | | | | | - Fusun Kilic
- To whom correspondence should be addressed: Dept. of Biochemistry and Molecular Biology, College of Medicine, University of Arkansas for Medical Sciences, 4301 West Markham St., 516, Little Rock, AR 72205. Tel.: 501-526-6488; Fax: 501-686-8169;
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50
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Ghiggeri GM, Caridi G, Magrini U, Sessa A, Savoia A, Seri M, Pecci A, Romagnoli R, Gangarossa S, Noris P, Sartore S, Necchi V, Ravazzolo R, Balduini CL. Genetics, clinical and pathological features of glomerulonephritis associated with mutations of nonmuscle myosin IIA (Fechtner syndrome). Am J Kidney Dis 2003; 41:95-104. [PMID: 12500226 DOI: 10.1053/ajkd.2003.50028] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Fechtner syndrome (FTNS), also known as Alport-like syndrome, is a rare inherited condition characterized by progressive nephritis, macrothrombocytopenia, Döhle-like leukocyte inclusions, deafness, and cataract. Although it recently was shown that FTNS derives from mutation of MYH9, the gene for the heavy chain of nonmuscle myosin IIA (NMMHC-IIA), its pathophysiological characteristics remain unknown. METHODS We studied a large FTNS family in which 10 components carried a missense mutation of MYH9 determining the D1424H substitution. RESULTS All affected subjects presented with macrothrombocytopenia and leukocyte Döhle-like bodies consisting of macroaggregates of NMMHC-IIA, but only two subjects had major renal problems characterized by proteinuria and renal failure. Electron microscopy showed focal and segmental effacement of podocytes and loss of the interpodocyte slit diaphragm. Immunohistochemistry showed apical localization of NMMHC-IIA in tubular epithelia and less podocyte staining in the two patients, whereas it was diffuse in normal epithelia. Three patients presented with stable microhematuria, and another five patients had no renal lesions, although they carried the same mutation of MYH9. Therefore, MYH9 mutation per se was responsible for platelet and leukocyte abnormalities, whereas additional predisposing conditions and/or environmental factors are necessary for nephropathy, cataract, and deafness. Looking at podocyte components conferring permselectivity properties to the kidney, we characterized the haplotype of podocin and found cosegregation of one specific allele in the two patients with nephrotic syndrome, suggesting a relationship between podocin features and proteinuria. CONCLUSION Our study indicates a major role for the NMMHC-IIA abnormality in the pathogenesis of leukocyte, platelet, and kidney defects in FTNS. The basic feature in all cases is aggregation and compartmentation of NMMHC-IIA. However, proteinuria and podocyte lesions are the hallmark of nephropathy in patients who develop renal failure, and podocin may have some function in this setting.
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Affiliation(s)
- Gian Marco Ghiggeri
- Laboratory on Pathophysiology of Uremia and Laboratory of Molecular Genetics, Istituto di Ricerca e Cura a Carattere Scientifico G. Gaslini, Genova, Italy.
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