1
|
Florkowska A, Meszka I, Zawada M, Legutko D, Proszynski TJ, Janczyk-Ilach K, Streminska W, Ciemerych MA, Grabowska I. Pax7 as molecular switch regulating early and advanced stages of myogenic mouse ESC differentiation in teratomas. Stem Cell Res Ther 2020; 11:238. [PMID: 32552916 PMCID: PMC7301568 DOI: 10.1186/s13287-020-01742-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/15/2020] [Accepted: 05/25/2020] [Indexed: 12/17/2022] Open
Abstract
Background Pluripotent stem cells present the ability to self-renew and undergo differentiation into any cell type building an organism. Importantly, a lot of evidence on embryonic stem cell (ESC) differentiation comes from in vitro studies. However, ESCs cultured in vitro do not necessarily behave as cells differentiating in vivo. For this reason, we used teratomas to study early and advanced stages of in vivo ESC myogenic differentiation and the role of Pax7 in this process. Pax7 transcription factor plays a crucial role in the formation and differentiation of skeletal muscle precursor cells during embryonic development. It controls the expression of other myogenic regulators and also acts as an anti-apoptotic factor. It is also involved in the formation and maintenance of satellite cell population. Methods In vivo approach we used involved generation and analysis of pluripotent stem cell-derived teratomas. Such model allows to analyze early and also terminal stages of tissue differentiation, for example, terminal stages of myogenesis, including the formation of innervated and vascularized mature myofibers. Results We determined how the lack of Pax7 function affects the generation of different myofiber types. In Pax7−/− teratomas, the skeletal muscle tissue occupied significantly smaller area, as compared to Pax7+/+ ones. The proportion of myofibers expressing Myh3 and Myh2b did not differ between Pax7+/+ and Pax7−/− teratomas. However, the area of Myh7 and Myh2a myofibers was significantly lower in Pax7−/− ones. Molecular characteristic of skeletal muscles revealed that the levels of mRNAs coding Myh isoforms were significantly lower in Pax7−/− teratomas. The level of mRNAs encoding Pax3 was significantly higher, while the expression of Nfix, Eno3, Mck, Mef2a, and Itga7 was significantly lower in Pax7−/− teratomas, as compared to Pax7+/+ ones. We proved that the number of satellite cells in Pax7−/− teratomas was significantly reduced. Finally, analysis of neuromuscular junction localization in samples prepared with the iDISCO method confirmed that the organization of neuromuscular junctions in Pax7−/− teratomas was impaired. Conclusions Pax7−/− ESCs differentiate in vivo to embryonic myoblasts more readily than Pax7+/+ cells. In the absence of functional Pax7, initiation of myogenic differentiation is facilitated, and as a result, the expression of mesoderm embryonic myoblast markers is upregulated. However, in the absence of functional Pax7 neuromuscular junctions, formation is abnormal, what results in lower differentiation potential of Pax7−/− ESCs during advanced stages of myogenesis.
Collapse
Affiliation(s)
- Anita Florkowska
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Igor Meszka
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Magdalena Zawada
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Diana Legutko
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland.,Laboratory of Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Tomasz J Proszynski
- Laboratory of Synaptogenesis, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.,Present Address: Lukasiewicz Research Network - PORT Polish Center for Technology Development, Wroclaw, Poland
| | - Katarzyna Janczyk-Ilach
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Wladyslawa Streminska
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Maria A Ciemerych
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Iwona Grabowska
- Department of Cytology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland.
| |
Collapse
|
2
|
An alternate protocol for establishment of primary caprine fetal myoblast cell culture: an in vitro model for muscle growth study. In Vitro Cell Dev Biol Anim 2013; 49:589-97. [PMID: 23739872 DOI: 10.1007/s11626-013-9642-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 05/19/2013] [Indexed: 12/17/2022]
Abstract
Cultured myoblasts have been used extensively as an in vitro model in understanding the underlying mechanisms of myogenesis. Various protocols for establishing a pure myoblast culture have been reported which involve the use of special procedures like flow cytometry and density gradient centrifugation. In goat, only a few protocols for establishing a myogenic cell culture are available and these protocols use adult muscle tissues which often does not yield sufficient numbers of precursor cells with adequate proliferative capacity. Considering the disadvantages of adult myoblasts, we are proposing an alternate protocol using caprine fetus which does not require any special procedures. In the present study, more than 90-95% fetal-derived cell populations had the typical spindle to polyhedral shape of myoblast cell and stained positive for desmin, hence confirming their myogenic origin. These cells attained the maximum confluency as early as 3-4 d against 3 wk by adult myoblasts indicating a better growth potential. Further, quantitative real-time PCR analysis revealed a higher expression (p < 0.01) of myogenic regulatory factors (i.e., myogenic determination factor 1, myogenic factor 5, and myogenin) and myostatin (MSTN) in the fetal as compared to the adult myoblasts. Consequently, higher proliferation and differentiation ability along with higher abundance of myogenic markers and MSTN make the fetal myoblasts a better in vitro model.
Collapse
|
3
|
Mahmood A, Harkness L, Schrøder HD, Abdallah BM, Kassem M. Enhanced differentiation of human embryonic stem cells to mesenchymal progenitors by inhibition of TGF-beta/activin/nodal signaling using SB-431542. J Bone Miner Res 2010; 25:1216-33. [PMID: 20200949 DOI: 10.1002/jbmr.34] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Directing differentiation of human embryonic stem cells (hESCs) into specific cell types using an easy and reproducible protocol is a prerequisite for the clinical use of hESCs in regenerative-medicine procedures. Here, we report a protocol for directing the differentiation of hESCs into mesenchymal progenitor cells. We demonstrate that inhibition of transforming growth factor beta (TGF-beta)/activin/nodal signaling during embryoid body (EB) formation using SB-431542 (SB) in serum-free medium markedly upregulated paraxial mesodermal markers (TBX6, TBX5) and several myogenic developmental markers, including early myogenic transcriptional factors (Myf5, Pax7), as well as myocyte-committed markers [NCAM, CD34, desmin, MHC (fast), alpha-smooth muscle actin, Nkx2.5, cTNT]. Continuous inhibition of TGF-beta signaling in EB outgrowth cultures (SB-OG) enriched for myocyte progenitor cells; markers were PAX7(+) (25%), MYOD1(+) (52%), and NCAM(+) (CD56) (73%). DNA microarray analysis revealed differential upregulation of 117 genes (>2-fold compared with control cells) annotated to myogenic development and function. Moreover, these cells showed the ability to contract (80% of the population) and formed myofibers when implanted intramuscularly in vivo. Interestingly, SB-OG cells cultured in 10% fetal bovine serum (FBS) developed into a homogeneous population of mesenchymal progenitors that expressed CD markers characteristic of mesenchymal stem cells (MSCs): CD44(+) (100%), CD73(+) (98%), CD146(+) (96%), and CD166(+) (88%) with the ability to differentiate into osteoblasts, adipocytes, and chondrocytes in vitro and in vivo. Furthermore, microarray analysis of these cells revealed downregulation of genes related to myogenesis: MYH3 (-167.9-fold), ACTA1 (-161-fold), MYBPH (-139-fold), ACTC (-100.3-fold), MYH8 (-45.5-fold), and MYOT (-41.8-fold) and marked upregulation of genes related to mesoderm-derived cell lineages. In conclusion, our data provides a simple and versatile protocol for directing the differentiation of hESCs into a myogenic lineage and then further into mesenchymal progenitors by blocking the TGF-beta signaling pathway.
Collapse
Affiliation(s)
- Amer Mahmood
- Medical Biotechnology Centre, Department of Endocrinology, University Hospital of Odense, University of South Denmark, Odense, Denmark
| | | | | | | | | |
Collapse
|
4
|
Janot M, Audfray A, Loriol C, Germot A, Maftah A, Dupuy F. Glycogenome expression dynamics during mouse C2C12 myoblast differentiation suggests a sequential reorganization of membrane glycoconjugates. BMC Genomics 2009; 10:483. [PMID: 19843320 PMCID: PMC2772862 DOI: 10.1186/1471-2164-10-483] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Accepted: 10/20/2009] [Indexed: 11/10/2022] Open
Abstract
Background Several global transcriptomic and proteomic approaches have been applied in order to obtain new molecular insights on skeletal myogenesis, but none has generated any specific data on glycogenome expression, and thus on the role of glycan structures in this process, despite the involvement of glycoconjugates in various biological events including differentiation and development. In the present study, a quantitative real-time RT-PCR technology was used to profile the dynamic expression of 375 glycogenes during the differentiation of C2C12 myoblasts into myotubes. Results Of the 276 genes expressed, 95 exhibited altered mRNA expression when C2C12 cells differentiated and 37 displayed more than 4-fold up- or down-regulations. Principal Component Analysis and Hierarchical Component Analysis of the expression dynamics identified three groups of coordinately and sequentially regulated genes. The first group included 12 down-regulated genes, the second group four genes with an expression peak at 24 h of differentiation, and the last 21 up-regulated genes. These genes mainly encode cell adhesion molecules and key enzymes involved in the biosynthesis of glycosaminoglycans and glycolipids (neolactoseries, lactoseries and ganglioseries), providing a clearer indication of how the plasma membrane and extracellular matrix may be modified prior to cell fusion. In particular, an increase in the quantity of ganglioside GM3 at the cell surface of myoblasts is suggestive of its potential role during the initial steps of myogenic differentiation. Conclusion For the first time, these results provide a broad description of the expression dynamics of glycogenes during C2C12 differentiation. Among the 37 highly deregulated glycogenes, 29 had never been associated with myogenesis. Their biological functions suggest new roles for glycans in skeletal myogenesis.
Collapse
Affiliation(s)
- Mathilde Janot
- INRA, UMR 1061 Unité de Génétique Moléculaire Animale, Université de Limoges, Faculté des Sciences et Techniques, 123 Avenue A, Thomas, 87060 Limoges, France.
| | | | | | | | | | | |
Collapse
|
5
|
Liu J, Gurpur PB, Kaufman SJ. Genetically determined proteolytic cleavage modulates alpha7beta1 integrin function. J Biol Chem 2008; 283:35668-78. [PMID: 18940796 PMCID: PMC2602887 DOI: 10.1074/jbc.m804661200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 10/14/2008] [Indexed: 01/07/2023] Open
Abstract
The dystrophin-glycoprotein complex and the alpha7beta1 integrin are trans-sarcolemmal linkage systems that connect and transduce contractile forces between muscle fibers and the extracellular matrix. alpha7beta1 is the major laminin binding integrin in skeletal muscle. Different functional variants of this integrin are generated by alternative splicing and post-translational modifications such as glycosylation and ADP-ribosylation. Here we report a species-specific difference in alpha7 chains that results from an intra-peptide proteolytic cleavage, by a serine protease, at the 603RRQ605 site. Site-directed mutagenesis of RRQ to GRQ prevents this cleavage. This RRQ sequence in the alpha7 integrin chain is highly conserved among vertebrates but it is absent in mice. Protein structure modeling indicates this cleavage site is located in an open region between the beta-propeller and thigh domains of the alpha7 chain. Compared with the non-cleavable alpha7 chain, the cleaved form enhances cell adhesion and spreading on laminin. Cleavage of the alpha7 chain is elevated upon myogenic differentiation, and this cleavage may be mediated by urokinase-type plasminogen activator. These results suggest proteolytic cleavage is a novel mechanism that regulates alpha7 integrin functions in skeletal muscle, and that the generation of such cleavage sites is another evolutionary mechanism for expanding and modifying protein functions.
Collapse
Affiliation(s)
- Jianming Liu
- Department of Cell and Developmental Biology, University of Illinois, Urbana, Illinois 61801, USA
| | | | | |
Collapse
|
6
|
Yan W, George S, Fotadar U, Tyhovych N, Kamer A, Yost MJ, Price RL, Haggart CR, Holmes JW, Terracio L. Tissue engineering of skeletal muscle. ACTA ACUST UNITED AC 2008; 13:2781-90. [PMID: 17880268 DOI: 10.1089/ten.2006.0408] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Loss of skeletal muscle profoundly affects the health and well-being of patients, and there currently is no way to replace lost muscle. We believe that a key step in the development of a prosthesis for reconstruction of dysfunctional muscular tissue is the ability to reconstitute the in vivo-like 3-dimensional (3D) organization of skeletal muscle in vitro with isolated satellite cells. In our present proof of principle studies, we have successfully constructed a multilayered culture of skeletal muscle cells, derived from neonatal satellite cells, that are distributed in a 3D pattern of organization that mimics many of the features of intact tissue. These multilayered cultures are composed of elongated multinucleated myotubes that are MyoD positive. Histological studies indicate that the multiple layers of myotubes can be distinguished. Expression of muscle-specific markers such as myosin heavy chain, dystrophin, integrin alpha-7, alpha-enolase, and beta-enolase was detected using real-time reverse transcriptase polymerase chain reaction at levels near adult values. Physiological measurements of the engineered skeletal muscle showed that they tetanize and display physiologic force length behavior, although developed force per cross-sectional area was below that of native rat skeletal muscle.
Collapse
Affiliation(s)
- Wentao Yan
- Department of Basic Sciences, New York University, New York, New York 10010, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Differential roles of HIC-5 isoforms in the regulation of cell death and myotube formation during myogenesis. Exp Cell Res 2007; 313:4000-14. [PMID: 17935713 DOI: 10.1016/j.yexcr.2007.05.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 05/16/2007] [Accepted: 05/16/2007] [Indexed: 11/21/2022]
Abstract
Hic-5 is a LIM-Only member of the paxillin superfamily of focal adhesion proteins. It has been shown to regulate a range of biological processes including: senescence, tumorigenesis, steroid hormone action, integrin signaling, differentiation, and apoptosis. To better understand the roles of Hic-5 during development, we initiated a detailed analysis of Hic-5 expression and function in C(2)C(12) myoblasts, a well-established model for myogenesis. We have found that: (1) myoblasts express at least 6 distinct Hic-5 isoforms; (2) the two predominant isoforms, Hic-5alpha and Hic-5beta, are differentially expressed during myogenesis; (3) any experimentally induced change in Hic-5 expression results in a substantial increase in apoptosis during differentiation; (4) ectopic expression of Hic-5alpha is permissive to differentiation while expression of either Hic-5beta or antisense Hic-5 blocks myoblast fusion but not chemodifferentiation; (5) Hic-5 localizes to focal adhesions in C(2)C(12) myoblasts and perturbation of Hic-5 leads to defects in cell spreading; (6) alterations in Hic-5 expression interfere with the normal dynamics of laminin expression; and (7) ectopic laminin, but not fibronectin, can rescue the Hic-5-induced blockade of myoblast survival and differentiation. Our data demonstrate differential roles for individual Hic-5 isoforms during myogenesis and support the hypothesis that Hic-5 mediates these effects via integrin signaling.
Collapse
|
8
|
Biressi S, Tagliafico E, Lamorte G, Monteverde S, Tenedini E, Roncaglia E, Ferrari S, Ferrari S, Cusella-De Angelis MG, Tajbakhsh S, Cossu G. Intrinsic phenotypic diversity of embryonic and fetal myoblasts is revealed by genome-wide gene expression analysis on purified cells. Dev Biol 2007; 304:633-51. [PMID: 17292343 DOI: 10.1016/j.ydbio.2007.01.016] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 11/29/2006] [Accepted: 01/05/2007] [Indexed: 12/30/2022]
Abstract
Skeletal muscle development occurs asynchronously and it has been proposed to be dependent upon the generation of temporally distinct populations of myogenic cells. This long-held hypothesis has not been tested directly due to the inability to isolate and analyze purified populations of myoblasts derived from specific stages of prenatal development. Using a mouse strain with the GFP reporter gene targeted into the Myf5 locus, a cell-sorting method was developed for isolating embryonic and fetal myoblasts. The two types of myoblasts show an intrinsic difference in fusion ability, proliferation, differentiation and response to TGFbeta, TPA and BMP-4 in vitro. Microarray and quantitative PCR were used to identify differentially expressed genes both before and after differentiation, thus allowing a precise phenotypic analysis of the two populations. Embryonic and fetal myoblasts differ in the expression of a number of transcription factors and surface molecules, which may control different developmental programs. For example, only embryonic myoblasts express a Hox code along the antero-posterior axis, indicating that they possess direct positional information. Taken together, the data presented here demonstrate that embryonic and fetal myoblasts represent intrinsically different myogenic lineages and provide important information for the understanding of the molecular mechanisms governing skeletal muscle development.
Collapse
Affiliation(s)
- Stefano Biressi
- Stem Cell Research Institute, Dibit, H. San Raffaele, via Olgettina 58, 20132 Milan, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Brzóska E, Bello V, Darribère T, Moraczewski J. Integrin α3 subunit participates in myoblast adhesion and fusion in vitro. Differentiation 2006; 74:105-18. [PMID: 16533309 DOI: 10.1111/j.1432-0436.2005.00059.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Satellite cells are myogenic precursor cells, participating in growth, and regeneration of skeletal muscles. The proteins that play a role in myogenesis are integrins. In this report, we show that the integrin alpha3 subunit is expressed in quiescent satellite cells and activated myoblasts. We also find that in myoblasts the integrin alpha3 subunit is localized at cell-cell and cell-extracellular matrix contacts. We notice that increase in protein and mRNA encoding the integrin alpha3 subunit accompanies myoblast differentiation. Using double immunofluorescence and immunoprecipitation experiments, we demonstrate that the integrin alpha3 subunit co-localizes with actin, and binds the integrin beta1 subunit and ADAM12, suggesting that the complex alpha3beta1/ADAM12 is probably involved in myoblast fusion. Importantly, overexpression of the full-length integrin alpha3 subunit increases myoblast fusion whereas an antibody against its extracellular domain inhibits fusion. These data demonstrate that the integrin alpha3 subunit may contribute to satellite cell activation and then myoblast adhesion and fusion.
Collapse
Affiliation(s)
- Edyta Brzóska
- Faculty of Biology, Department of Cytology, Warsaw University, 1 Miecznikowa St., 02-096 Warsaw, Poland.
| | | | | | | |
Collapse
|
10
|
Zolkiewska A. Ecto-ADP-ribose transferases: cell-surface response to local tissue injury. Physiology (Bethesda) 2006; 20:374-81. [PMID: 16287986 DOI: 10.1152/physiol.00028.2005] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ecto-ADP-ribose transferases (ecto-ARTs) catalyze the transfer of ADP-ribose from NAD(+) to arginine residues in cell-surface proteins. Since the concentration of extracellular NAD(+) is very low under normal physiological conditions but rises significantly upon tissue injury or membrane stress, it is postulated that the main role of ecto-ARTs is to ADP-ribosylate and regulate the function of certain membrane receptors in response to elevated levels of NAD(+).
Collapse
Affiliation(s)
- Anna Zolkiewska
- Department of Biochemistry, Kansas State University, Manhattan, USA.
| |
Collapse
|
11
|
Muroya S, Nakajima I, Oe M, Chikuni K. Effect of phase limited inhibition of MyoD expression on the terminal differentiation of bovine myoblasts: no alteration of Myf5 or myogenin expression. Dev Growth Differ 2006; 47:483-92. [PMID: 16179075 DOI: 10.1111/j.1440-169x.2005.00822.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To investigate the roles played by MyoD in the terminal differentiation of satellite cell-derived myoblasts, the effect of antisense inhibition of MyoD expression was examined in bovine adult myoblast culture, in which inhibition treatment was limited to the terminal differentiation phase. MyoD antisense oligonucleotide DNA (AS-mD) suppressed the formation of multinucleated myotubes in the cell culture. Myotube formation was suppressed even when AS-mD treatment was limited to the period preceding the onset of myotube formation. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis revealed that treatment with AS-mD suppressed the expression of myosin heavy chain embryonic isoform and troponin T isoforms at 4 days after the induction of differentiation. AS-mD also suppressed the expression of MRF4, but did not alter the expression of either Myf5 or myogenin, in contrast to previous results using mouse cells possessing MyoD(-/-) genetic background. These findings suggest that MyoD controls myogenesis but not Myf5 or myogenin mRNA expression during the terminal differentiation phase. Furthermore, among the alpha4, alpha5, alpha6, and alpha7 integrins, alpha4, alpha5, and alpha7 integrin expression was suppressed by AS-mD treatment, in parallel with the suppression of myotube formation, which suggests that MyoD controls myotube formation by regulating the expression of alpha4, alpha5, and alpha7 integrins.
Collapse
Affiliation(s)
- Susumu Muroya
- Department of Animal Products, National Institute of Livestock and Grassland Science, Tsukuba, Ibaraki 305-0901, Japan.
| | | | | | | |
Collapse
|
12
|
Cachaço AS, Pereira CS, Pardal RG, Bajanca F, Thorsteinsdóttir S. Integrin repertoire on myogenic cells changes during the course of primary myogenesis in the mouse. Dev Dyn 2005; 232:1069-78. [PMID: 15739233 DOI: 10.1002/dvdy.20280] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Cells interact with the extracellular matrix through receptors, most commonly of the integrin family. We (Cachaco et al. [2003] Development 130:1659-1671) and others (Schwander et al. [2003] Dev. Cell 4:673-685) have demonstrated a role for beta1 integrins in mouse primary myogenesis. However, it is unclear what alpha subunits pair with beta1 during this process in vivo. Here, we determined alpha subunit expression patterns at embryonic day (E) 11.5-E14.5. Differentiated myotomal myocytes express all alpha subunits studied. As the muscle masses form both in trunk (E12.5) and limbs (E11.5-E12.5), laminin receptors alpha6beta1 and alpha7beta1 are undetectable, and an assembled laminin matrix is absent. Instead alpha1beta1, alpha4beta1, alpha5beta1, and an alpha v-containing integrin are expressed and unassembled laminin and fibronectin are abundant around myogenic cells. At E13.5-E14.5, alpha6beta1 and alpha7beta1 are expressed, and a laminin matrix forms around individual myotubes. Thus, myogenic cells change their integrin expression pattern during the course of primary myogenesis in the mouse, suggesting different roles for fibronectin- and laminin-containing matrices in this process.
Collapse
Affiliation(s)
- Ana Sofia Cachaço
- Departamento de Biologia Animal, Centro de Biologia Ambiental, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | | | | | | | | |
Collapse
|
13
|
Lafuste P, Sonnet C, Chazaud B, Dreyfus PA, Gherardi RK, Wewer UM, Authier FJ. ADAM12 and alpha9beta1 integrin are instrumental in human myogenic cell differentiation. Mol Biol Cell 2004; 16:861-70. [PMID: 15574885 PMCID: PMC545917 DOI: 10.1091/mbc.e04-03-0226] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Knowledge on molecular systems involved in myogenic precursor cell (mpc) fusion into myotubes is fragmentary. Previous studies have implicated the a disintegrin and metalloproteinase (ADAM) family in most mammalian cell fusion processes. ADAM12 is likely involved in fusion of murine mpc and human rhabdomyosarcoma cells, but it requires yet unknown molecular partners to launch myogenic cell fusion. ADAM12 was shown able to mediate cell-to-cell attachment through binding alpha9beta1 integrin. We report that normal human mpc express both ADAM12 and alpha9beta1 integrin during their differentiation. Expression of alpha9 parallels that of ADAM12 and culminates at time of fusion. alpha9 and ADAM12 coimmunoprecipitate and participate to mpc adhesion. Inhibition of ADAM12/alpha9beta1 integrin interplay, by either ADAM12 antisense oligonucleotides or blocking antibody to alpha9beta1, inhibited overall mpc fusion by 47-48%, with combination of both strategies increasing inhibition up to 62%. By contrast with blockade of vascular cell adhesion molecule-1/alpha4beta1, which also reduced fusion, exposure to ADAM12 antisense oligonucleotides or anti-alpha9beta1 antibody did not induce detachment of mpc from extracellular matrix, suggesting specific involvement of ADAM12-alpha9beta1 interaction in the fusion process. Evaluation of the fusion rate with regard to the size of myotubes showed that both ADAM12 antisense oligonucleotides and alpha9beta1 blockade inhibited more importantly formation of large (> or =5 nuclei) myotubes than that of small (2-4 nuclei) myotubes. We conclude that both ADAM12 and alpha9beta1 integrin are expressed during postnatal human myogenic differentiation and that their interaction is mainly operative in nascent myotube growth.
Collapse
Affiliation(s)
- Peggy Lafuste
- Institut National de la Santé et de la Recherche Médicale EMI 0011, Faculty of Medicine, Paris XII University, Creteil 94010, France
| | | | | | | | | | | | | |
Collapse
|
14
|
Kjaer M. Role of extracellular matrix in adaptation of tendon and skeletal muscle to mechanical loading. Physiol Rev 2004; 84:649-98. [PMID: 15044685 DOI: 10.1152/physrev.00031.2003] [Citation(s) in RCA: 953] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The extracellular matrix (ECM), and especially the connective tissue with its collagen, links tissues of the body together and plays an important role in the force transmission and tissue structure maintenance especially in tendons, ligaments, bone, and muscle. The ECM turnover is influenced by physical activity, and both collagen synthesis and degrading metalloprotease enzymes increase with mechanical loading. Both transcription and posttranslational modifications, as well as local and systemic release of growth factors, are enhanced following exercise. For tendons, metabolic activity, circulatory responses, and collagen turnover are demonstrated to be more pronounced in humans than hitherto thought. Conversely, inactivity markedly decreases collagen turnover in both tendon and muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as, dependent on the type of collagen in question, some degree of net collagen synthesis. These changes will modify the mechanical properties and the viscoelastic characteristics of the tissue, decrease its stress, and likely make it more load resistant. Cross-linking in connective tissue involves an intimate, enzymatical interplay between collagen synthesis and ECM proteoglycan components during growth and maturation and influences the collagen-derived functional properties of the tissue. With aging, glycation contributes to additional cross-linking which modifies tissue stiffness. Physiological signaling pathways from mechanical loading to changes in ECM most likely involve feedback signaling that results in rapid alterations in the mechanical properties of the ECM. In developing skeletal muscle, an important interplay between muscle cells and the ECM is present, and some evidence from adult human muscle suggests common signaling pathways to stimulate contractile and ECM components. Unaccostumed overloading responses suggest an important role of ECM in the adaptation of myofibrillar structures in adult muscle. Development of overuse injury in tendons involve morphological and biochemical changes including altered collagen typing and fibril size, hypervascularization zones, accumulation of nociceptive substances, and impaired collagen degradation activity. Counteracting these phenomena requires adjusted loading rather than absence of loading in the form of immobilization. Full understanding of these physiological processes will provide the physiological basis for understanding of tissue overloading and injury seen in both tendons and muscle with repetitive work and leisure time physical activity.
Collapse
Affiliation(s)
- Michael Kjaer
- Sports Medicine Research Unit, Department of Rheumatology, Copenhagen University Hospital at Bispebjerg, 23 Bispebjerg Bakke, DK-2400 Copenhagen NV, Denmark.
| |
Collapse
|
15
|
Purslow PP. The structure and functional significance of variations in the connective tissue within muscle. Comp Biochem Physiol A Mol Integr Physiol 2002; 133:947-66. [PMID: 12485685 DOI: 10.1016/s1095-6433(02)00141-1] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The amount of intramuscular connective tissue (IMCT) and its morphological distribution is highly variable between muscles of differing function. The functional roles of this component of muscle have been poorly understood, but a picture is gradually emerging of the central role this component has in growth, transmission of mechanical signals to muscle cells and co-ordination of forces between fibres within a muscle. The aim of this review is to highlight recent advances that begin to show the functional significance of some of the variability in IMCT. IMCT has a number of clearly defined roles. It patterns muscle development and innervation, and mechanically integrates the tissue. In developing muscles, proliferation and growth of muscle cells is stimulated and guided by cell-matrix interactions. Recent work has shown that the topography of collagen fibres is an important signal. The timing and rates of expression of connective tissue proteins also show differences between muscles. Discussion of mechanical roles for IMCT has traditionally been limited to the passive elastic response of muscle. However, it is now clear that IMCT provides a matrix to integrate the contractile function of the whole tissue. Mechanical forces are co-ordinated and passed between adjacent muscle cells via cell-matrix interactions and the endomysial connective tissue that links the cells together. An emerging concept is that division of a muscle into fascicles by the perimysial connective tissue is related to the need to accommodate shear strains as muscles change shape during contraction and extension.
Collapse
Affiliation(s)
- Peter P Purslow
- Department of Biological Sciences, University of Stirling, Stirling FK9 4LA, Scotland, UK.
| |
Collapse
|
16
|
von der Mark H, Williams I, Wendler O, Sorokin L, von der Mark K, Pöschl E. Alternative splice variants of alpha 7 beta 1 integrin selectively recognize different laminin isoforms. J Biol Chem 2002; 277:6012-6. [PMID: 11744715 DOI: 10.1074/jbc.m102188200] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The integrin alpha(7)beta(1) occurs in several cytoplasmic (alpha(7A), alpha(7B)) and extracellular splice variants (alpha(7X1), alpha(7X2)), which are differentially expressed during development of skeletal and heart muscle. The extracellular variants result from the alternative splicing of exons X1 and X2, corresponding to a segment within the putative ligand binding domain. To study the specificity and affinity of the X1/X2 variants to different laminin isoforms, soluble alpha(7)beta(1) complexes were prepared by recombinant coexpression of the extracellular domains of the alpha- and beta-subunits. The binding of these complexes to purified ligands was measured by solid phase binding assays. Surprisingly, the alternative splice variants revealed different and specific affinities to different laminin isoforms. While the alpha(7X2) variant bound much more strongly to laminin-1 than the alpha(7X1) variant, the latter showed a high affinity binding to laminins-8 and -10/11. Laminin-2, the major laminin isoform in skeletal muscle, was recognized by both variants, whereas none of the two variants were able to interact with laminin-5. A specific blocking antibody inhibited the binding of both variants to all laminins tested, indicating the involvement of common epitopes in alpha(7X1)beta(1) and alpha(7X2)beta(1). Because laminin-8 and -10/11 as well as alpha(7X1) are expressed in developing skeletal and cardiac muscle, these findings suggest that alpha(7X1)beta(1) may represent a physiological receptor with novel specificities for laminin-8 and -10.
Collapse
Affiliation(s)
- Helga von der Mark
- Friedrich-Alexander-Universität Erlangen-Nürnberg, Nikolaus-Fiebiger-Zentrum für Molekulare Medizin, Department of Experimental Medicine I, 91054 Erlangen, Germany
| | | | | | | | | | | |
Collapse
|
17
|
Blanco-Bose WE, Yao CC, Kramer RH, Blau HM. Purification of mouse primary myoblasts based on alpha 7 integrin expression. Exp Cell Res 2001; 265:212-20. [PMID: 11302686 DOI: 10.1006/excr.2001.5191] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fundamental insights have come from the study of myogenesis. Primary myoblasts isolated directly from muscle tissue more closely approximate myogenesis than established cell lines. However, contamination of primary muscle cultures with nonmyogenic cells can complicate the results. To overcome this problem, we previously described a method for myoblast purification based on novel culture conditions (T. A. Rando and H. M. Blau, 1994, J. Cell Biol. 125, 1275--1287). Here we report a refinement of this method that leads directly to an enriched population of mouse primary myoblasts, within significantly fewer population doublings. The method described here avoids using adhesion as a criterion for selection. This advance capitalizes on the ability of the antibody CA5.5 to recognize alpha 7 integrin, a muscle-specific cell surface antigen. Enrichment of myoblasts to greater than 95% of the cell population can be achieved by a single round of flow cytometry or magnetic bead separation. This is the first description of a mouse myoblast purification method based on a cell-type-specific antigen. The ease of this procedure for isolating primary myoblasts should expand the opportunities for (1) using these cells in cell transplantation studies in animal models of human disease, (2) isolating and characterizing mutant myoblasts from transgenic animals, and (3) allowing in vitro studies of molecules that regulate muscle cell growth, differentiation, and neoplasia.
Collapse
Affiliation(s)
- W E Blanco-Bose
- Department of Molecular Pharmacology, Stanford University School of Medicine, Stanford, California 94305-5175, USA
| | | | | | | |
Collapse
|