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Evodevo
2013 Dec 02;41:33. doi: 10.1186/2041-9139-4-33.
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Myogenesis in the sea urchin embryo: the molecular fingerprint of the myoblast precursors.
Andrikou C
,
Iovene E
,
Rizzo F
,
Oliveri P
,
Arnone MI
.
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BACKGROUND: In sea urchin larvae the circumesophageal fibers form a prominent muscle system of mesodermal origin. Although the morphology and later development of this muscle system has been well-described, little is known about the molecular signature of these cells or their precise origin in the early embryo. As an invertebrate deuterostome that is more closely related to the vertebrates than other commonly used model systems in myogenesis, the sea urchin fills an important phylogenetic gap and provides a unique perspective on the evolution of muscle cell development.
RESULTS: Here, we present a comprehensive description of the development of the sea urchin larval circumesophageal muscle lineage beginning with its mesodermal origin using high-resolution localization of the expression of several myogenic transcriptional regulators and differentiation genes. A few myoblasts are bilaterally distributed at the oral vegetal side of the tip of the archenteron and first appear at the late gastrula stage. The expression of the differentiation genes Myosin Heavy Chain, Tropomyosin I and II, as well as the regulatory genes MyoD2, FoxF, FoxC, FoxL1, Myocardin, Twist, and Tbx6 uniquely identify these cells. Interestingly, evolutionarily conserved myogenic factors such as Mef2, MyoR and Six1/2 are not expressed in sea urchin myoblasts but are found in other mesodermal domains of the tip of the archenteron. The regulatory states of these domains were characterized in detail. Moreover, using a combinatorial analysis of gene expression we followed the development of the FoxF/FoxC positive cells from the onset of expression to the end of gastrulation. Our data allowed us to build a complete map of the Non-Skeletogenic Mesoderm at the very early gastrula stage, in which specific molecular signatures identify the precursors of different cell types. Among them, a small group of cells within the FoxY domain, which also express FoxC and SoxE, have been identified as plausible myoblast precursors. Together, these data support a very early gastrula stage segregation of the myogenic lineage.
CONCLUSIONS: From this analysis, we are able to precisely define the regulatory and differentiation signatures of the circumesophageal muscle in the sea urchin embryo. Our findings have important implications in understanding the evolution of development of the muscle cell lineage at the molecular level. The data presented here suggest a high level of conservation of the myogenic specification mechanisms across wide phylogenetic distances, but also reveal clear cases of gene cooption.
Figure 1. Progression of MHC-positive cell lineages during sea urchin development.MHC and Trop1 expression in the gastrula (40 to 48 h), prism, (48 to 60 h), early (60 to 72 h) and late pluteus stage (72 to 96 h) . Expression of MHC(A, F, K, P) and Trop1(B, G, L, Q) was localized by colorimetric in situ hybridization. The embryos in panels A and B are shown in a vegetal view; the ones in panels C-T are viewed along the animal top/vegetal down (A/V) axis. The inset in panel I is double fluorescent in situ hybridization (FISH) showing the co-expression of CapZ (green) and MHC (red) in myoblasts. Double FISH indicates that Trop1 (green) and MHC (red) are co-expressed in the muscles of a late pluteus (inset in Q). FISH was used to localize the expression of MHC (red; C, D, H, I, M, N, R, S). Bright field images (C, H, M, R) and confocal stacks (D, I, N, S) that include 4',6-diamidino-2-phenylindole (DAPI) (blue) staining are shown. Embryos in C, D, E and T are shown as lateral views with the oral side to the right. The ciliary band and gut internal cilia were stained anti-acetylated tubulin (shown as green in S). The inset is a magnified view of the muscle fibers from a single confocal plane. A schematic representation of the progression of MHC-positive cells in the formation of the muscle fibers is shown (E, J, O, T). Ventrolateral processes (v), the cardiac sphincter (cs; red arrow), the pyloric sphincter (ps; black arrow) and the anal sphincter (as; yellow arrow) are indicated. Muscle fibers are indicated as white (N, S) or black (O, T) arrows.
Figure 2. Whole mount in situ hybridization (WMISH) of sea urchin regulatory genes whose orthologs are known myogenic factors.Sum1/MyoD1, MyoD2, MyoR, Maf, Myocardin, Mef2, Twist and Tbx6 expression was localized using WMISH at the gastrula (44 to 48 h; A-H), prism (60 to 65 h; A’-H’), and pluteus larva stage (72 to 80 h; A”-H”). All embryos are viewed along the animal top/vegetal down axis with the exceptions of panel A, which is shown in a vegetal view with the oral side on the bottom, B’, C’, D’ and H are viewed in a lateral view with the oral side on the left (B’) or right (C’, D’ and H’). Domains of expression other than the tip of the archenteron and the coelomic pouches are indicated as follows: black arrow, primary mesenchyme cells (PMC); black arrowhead, the cardiac sphincter; white arrowhead, the apical organ; black asterisk, the blastopore.
Figure 3. Co-expression analysis of putative sea urchin myogenic factors and MHC by double confocal fluoresecent in situ hybridization (FISH). Relative spatial domain of expression of FoxF(A), FoxC(B), FoxY(C), FoxL1(D), Six1/2(E), SoxE(F), MaF(G), Myocardin(H), MyoR2(I), Tbx6(J), Mef2(K), and Twist(L) (green) with respect to MHC (red) by double FISH in the late gastrula stage, 48 to 50 h. Every picture is a full projection of merged confocal stacks. Aside each picture are separately placed single focal planes of each channel plus a merged picture of an enlarged detail at the tip of the archenteron, to clarify any misleading issue of co-expression domains. In E, a single brightfield slice is also superimposed to the red channel. Yellow circles indicated by yellow arrowheads show co-expressing cells, and the white ones point to absence of co-expression. The white arrows indicate other domains of expression. All the embryos are viewed along the animal top/vegetal down (A/V) axis from the oral or aboral surface, excluding the one reported in L which is shown in a lateral view along the A/V axis with the oral side on the right. Nuclei are stained blue with 4',6-diamidino-2-phenylindole (DAPI).
Figure 4. Co-expression analysis of sea urchin putative regulatory factors at the tip of the archenteron by double confocal fluorescent in situ hybridization (FISH). Relative disposition of FoxF(A-C, E, H and K), FoxC(A, D and G), FoxY(D-F and J), FoxL1(C), Six1/2(K and L), SoxE(B, F, I and L), Tbx6(J) and SoxC(G-I) transcripts by double FISH in the late gastrula stage, 48 to 50 h. Every picture is a full projection of merged confocal stacks. FoxF is stained in red, FoxY and FoxL1 in green, FoxC in purple, Six1/2 and Tbx6 in magenta, SoxE in cyan and SoxC in yellow. Panel K is the only exception where Six1/2 is depicted in green. Full projection of split channels showing enlarged details of the tip of the archenteron are placed aside each picture. Yellow circles indicated by yellow arrowheads show cells co-expressing the analyzed genes. White arrows in G-I indicate the position of the presumptive anal and cardiac sphincters. The ectodermal staining in C corresponds to ciliary band expression of the FoxL1 gene. All the embryos are viewed in a lateral view along the animal top/vegetal down axis with the oral side on the left. Nuclei are labeled blue with 4',6-diamidino-2-phenylindole (DAPI).
Figure 5. Map of the regulatory state of the main mesodermal domains of the tip of the sea urchin archenteron at the late gastrula stage. (A) Schematic representation of a 48-h sea urchin embryo archenteron in lateral view along the animal top/vegetal down axis. The cell fate of each region is indicated as follows: Ab, aboral; An, animal; BC, blastocoelar cells; GC, germ cells; HC, hydropore canal; M, muscles; O, oral; V, vegetal. (B) Different mesodermal regions identified by specific regulatory signatures at the tip of the archenteron are shown in different colors distributed over the three major domains defined in this study. Regions of partial overlaps and names of the genes expressed in each region are shown in colors associated with each domain.
Figure 6. Dynamics of gene expression in the putative myoblast precursors of the sea urchin embryo. Fluorescent whole mount in situ hybridization and relative position of FoxY (green), FoxC (red) and FoxF (magenta) transcripts in the interval from 24 to 45 h. Each picture is a full projection of merged confocal stacks. Yellow circles indicated by yellow arrowheads show co-expression cells; white circles show absence of co-expression. White arrows in panel A indicate the emergence of FoxY transcription in the NSMs. For single-channel full projections of the images reported in D-I see Additional file 11: Figure S9. All the embryos are viewed in lateral view along the animal top/vegetal down axis with the exception of A, B and C that are seen in a vegetal view. Nuclei are labeled blue with 4',6-diamidino-2-phenylindole (DAPI).
Figure 7. Co-expression analysis of sea urchin putative myogenic factors and non-skeletogenic mesoderm (NSM) and small micromere (SM) molecular markers. (A-I) Expression of FoxC, FoxY, Ese, Gcm, Six1/2, SoxE, Tbx6 and Nanos was localized by double confocal fluorescent in situ hybridization at the very early gastrula stage, 30 to 32 h. Every picture is a full projection of merged confocal stacks. Yellow circles indicated by yellow arrowheads show co-expressing cells, and the white ones show absence of co-expression. For single-channel projections of the images reported in C, F and I see Additional file 11: Figure S9. All the embryos are viewed in a vegetal view with the exception of A, D, E, G and H that are seen in lateral view along the animal top/vegetal down axis. Nuclei are labeled blue with 4',6-diamidino-2-phenylindole (DAPI). In panels J and K a schematic representation is shown of a regulatory stage map of NSM of a 30-h sea urchin embryo orientated along the oral right/aboral left (O/Ab) axis in both lateral (J) and vegetal views (K). The different mesodermal cell types identified by specific regulatory signatures at the vegetal plate are shown in different colors: Mp, putative myoblast precursors, green with orange and red horizontal lines; BCp, blastocoelar cell precursors, yellow; PCp, pigment cell precursors, blue; SMd + Y, small micromere derivatives (SMd) plus FoxY expressing NSM cells (Y), green with an orange horizontal line. A legend indicates the names of the genes expressed in each region. For the sake of simplicity, primary mesenchyme cells are not shown.
Amin,
A Zn-finger/FH2-domain containing protein, FOZI-1, acts redundantly with CeMyoD to specify striated body wall muscle fates in the Caenorhabditis elegans postembryonic mesoderm.
2007, Pubmed
Amin,
A Zn-finger/FH2-domain containing protein, FOZI-1, acts redundantly with CeMyoD to specify striated body wall muscle fates in the Caenorhabditis elegans postembryonic mesoderm.
2007,
Pubmed
Atchley,
Molecular evolution of the MyoD family of transcription factors.
1994,
Pubmed
Baylies,
twist: a myogenic switch in Drosophila.
1996,
Pubmed
Beach,
Expression of the sea urchin MyoD homologue, SUM1, is not restricted to the myogenic lineage during embryogenesis.
1999,
Pubmed
,
Echinobase
Beh,
FoxF is essential for FGF-induced migration of heart progenitor cells in the ascidian Ciona intestinalis.
2007,
Pubmed
Bentzinger,
Building muscle: molecular regulation of myogenesis.
2012,
Pubmed
Bothe,
Extrinsic versus intrinsic cues in avian paraxial mesoderm patterning and differentiation.
2007,
Pubmed
Buckingham,
Myogenic progenitor cells and skeletal myogenesis in vertebrates.
2006,
Pubmed
Burke,
Development of the esophageal muscles in embryos of the sea urchin Strongylocentrotus purpuratus.
1988,
Pubmed
,
Echinobase
Cameron,
Cell type specification during sea urchin development.
1991,
Pubmed
,
Echinobase
Castanon,
A Twist in fate: evolutionary comparison of Twist structure and function.
2002,
Pubmed
Chen,
Body-wall muscle formation in Caenorhabditis elegans embryos that lack the MyoD homolog hlh-1.
1992,
Pubmed
Ciglar,
Conservation and divergence in developmental networks: a view from Drosophila myogenesis.
2009,
Pubmed
Cole,
Two ParaHox genes, SpLox and SpCdx, interact to partition the posterior endoderm in the formation of a functional gut.
2009,
Pubmed
,
Echinobase
Cole,
Fluorescent in situ hybridization reveals multiple expression domains for SpBrn1/2/4 and identifies a unique ectodermal cell type that co-expresses the ParaHox gene SpLox.
2009,
Pubmed
,
Echinobase
Creemers,
Myocardin is a direct transcriptional target of Mef2, Tead and Foxo proteins during cardiovascular development.
2006,
Pubmed
Dyachuk,
Larval myogenesis in Echinodermata: conserved features and morphological diversity between class-specific larval forms of Echinoidae, Asteroidea, and Holothuroidea.
2013,
Pubmed
,
Echinobase
Edmondson,
Mef2 gene expression marks the cardiac and skeletal muscle lineages during mouse embryogenesis.
1994,
Pubmed
Gustafson,
Cellular movement and contact in sea urchin morphogenesis.
1967,
Pubmed
,
Echinobase
Gyoja,
Expression of a muscle determinant gene, macho-1, in the anural ascidian Molgula tectiformis.
2006,
Pubmed
Hannenhalli,
The evolution of Fox genes and their role in development and disease.
2009,
Pubmed
Howard-Ashby,
Gene families encoding transcription factors expressed in early development of Strongylocentrotus purpuratus.
2006,
Pubmed
,
Echinobase
Ishimoda-Takagi,
Evidence for the involvement of muscle tropomyosin in the contractile elements of the coelom-esophagus complex in sea urchin embryos.
1984,
Pubmed
,
Echinobase
Ismat,
HLH54F is required for the specification and migration of longitudinal gut muscle founders from the caudal mesoderm of Drosophila.
2010,
Pubmed
Juliano,
Nanos functions to maintain the fate of the small micromere lineage in the sea urchin embryo.
2010,
Pubmed
,
Echinobase
Juliano,
Germ line determinants are not localized early in sea urchin development, but do accumulate in the small micromere lineage.
2006,
Pubmed
,
Echinobase
Kataoka,
Multiple mechanisms and functions of maf transcription factors in the regulation of tissue-specific genes.
2007,
Pubmed
Kugler,
Temporal regulation of the muscle gene cascade by Macho1 and Tbx6 transcription factors in Ciona intestinalis.
2010,
Pubmed
Kumar,
The sine oculis homeobox (SIX) family of transcription factors as regulators of development and disease.
2009,
Pubmed
Lu,
MyoR: a muscle-restricted basic helix-loop-helix transcription factor that antagonizes the actions of MyoD.
1999,
Pubmed
Luo,
Opposing nodal and BMP signals regulate left-right asymmetry in the sea urchin larva.
2012,
Pubmed
,
Echinobase
Materna,
Notch and Nodal control forkhead factor expression in the specification of multipotent progenitors in sea urchin.
2013,
Pubmed
,
Echinobase
Materna,
Diversification of oral and aboral mesodermal regulatory states in pregastrular sea urchin embryos.
2013,
Pubmed
,
Echinobase
Materna,
High accuracy, high-resolution prevalence measurement for the majority of locally expressed regulatory genes in early sea urchin development.
2010,
Pubmed
,
Echinobase
Mazet,
An ancient Fox gene cluster in bilaterian animals.
2006,
Pubmed
Meedel,
Muscle development in Ciona intestinalis requires the b-HLH myogenic regulatory factor gene Ci-MRF.
2007,
Pubmed
Minokawa,
Expression patterns of four different regulatory genes that function during sea urchin development.
2004,
Pubmed
,
Echinobase
Morris,
Analysis of cytoskeletal and motility proteins in the sea urchin genome assembly.
2006,
Pubmed
,
Echinobase
Nemer,
Polyubiquitin RNA characteristics and conditional induction in sea urchin embryos.
1991,
Pubmed
,
Echinobase
Nishida,
macho-1 encodes a localized mRNA in ascidian eggs that specifies muscle fate during embryogenesis.
2001,
Pubmed
Oliveri,
Development. Built to run, not fail.
2007,
Pubmed
Oliveri,
Global regulatory logic for specification of an embryonic cell lineage.
2008,
Pubmed
,
Echinobase
Ormestad,
Foxf1 and Foxf2 control murine gut development by limiting mesenchymal Wnt signaling and promoting extracellular matrix production.
2006,
Pubmed
Pehrson,
The fate of the small micromeres in sea urchin development.
1986,
Pubmed
,
Echinobase
Pipes,
The myocardin family of transcriptional coactivators: versatile regulators of cell growth, migration, and myogenesis.
2006,
Pubmed
Plickert,
Hydractinia, a pioneering model for stem cell biology and reprogramming somatic cells to pluripotency.
2012,
Pubmed
Potthoff,
MEF2: a central regulator of diverse developmental programs.
2007,
Pubmed
Poustka,
Generation, annotation, evolutionary analysis, and database integration of 20,000 unique sea urchin EST clusters.
2003,
Pubmed
,
Echinobase
Poustka,
A global view of gene expression in lithium and zinc treated sea urchin embryos: new components of gene regulatory networks.
2007,
Pubmed
,
Echinobase
Poustka,
Toward the gene catalogue of sea urchin development: the construction and analysis of an unfertilized egg cDNA library highly normalized by oligonucleotide fingerprinting.
1999,
Pubmed
,
Echinobase
Pownall,
Myogenic regulatory factors and the specification of muscle progenitors in vertebrate embryos.
2002,
Pubmed
Puri,
Regulation of muscle regulatory factors by DNA-binding, interacting proteins, and post-transcriptional modifications.
2000,
Pubmed
Pyle,
Actin capping protein: an essential element in protein kinase signaling to the myofilaments.
2002,
Pubmed
Ransick,
New early zygotic regulators expressed in endomesoderm of sea urchin embryos discovered by differential array hybridization.
2002,
Pubmed
,
Echinobase
Ransick,
Cis-regulatory logic driving glial cells missing: self-sustaining circuitry in later embryogenesis.
2012,
Pubmed
,
Echinobase
Rast,
Recovery of developmentally defined gene sets from high-density cDNA macroarrays.
2000,
Pubmed
,
Echinobase
Rizzo,
Identification and developmental expression of the ets gene family in the sea urchin (Strongylocentrotus purpuratus).
2006,
Pubmed
,
Echinobase
Rozen,
Primer3 on the WWW for general users and for biologist programmers.
2000,
Pubmed
Ruffins,
A fate map of the vegetal plate of the sea urchin (Lytechinus variegatus) mesenchyme blastula.
1996,
Pubmed
,
Echinobase
Schmidt,
Sox8 is a specific marker for muscle satellite cells and inhibits myogenesis.
2003,
Pubmed
Sherwood,
LvNotch signaling mediates secondary mesenchyme specification in the sea urchin embryo.
1999,
Pubmed
,
Echinobase
Shimeld,
Evolutionary genomics of the Fox genes: origin of gene families and the ancestry of gene clusters.
2010,
Pubmed
Solek,
An ancient role for Gata-1/2/3 and Scl transcription factor homologs in the development of immunocytes.
2013,
Pubmed
,
Echinobase
Song,
The forkhead transcription factor FoxY regulates Nanos.
2012,
Pubmed
,
Echinobase
Steinmetz,
Independent evolution of striated muscles in cnidarians and bilaterians.
2012,
Pubmed
Sweet,
LvDelta is a mesoderm-inducing signal in the sea urchin embryo and can endow blastomeres with organizer-like properties.
2002,
Pubmed
,
Echinobase
Tamboline,
Secondary mesenchyme of the sea urchin embryo: ontogeny of blastocoelar cells.
1992,
Pubmed
,
Echinobase
Tazumi,
PMesogenin1 and 2 function directly downstream of Xtbx6 in Xenopus somitogenesis and myogenesis.
2008,
Pubmed
Tazumi,
Paraxial T-box genes, Tbx6 and Tbx1, are required for cranial chondrogenesis and myogenesis.
2010,
Pubmed
Tu,
Sea urchin Forkhead gene family: phylogeny and embryonic expression.
2006,
Pubmed
,
Echinobase
Venuti,
Developmental potential of muscle cell progenitors and the myogenic factor SUM-1 in the sea urchin embryo.
1993,
Pubmed
,
Echinobase
Venuti,
A myogenic factor from sea urchin embryos capable of programming muscle differentiation in mammalian cells.
1991,
Pubmed
,
Echinobase
Walton,
Hedgehog signaling patterns mesoderm in the sea urchin.
2009,
Pubmed
,
Echinobase
Wang,
Maternal and embryonic provenance of a sea urchin embryo transcription factor, SpZ12-1.
1995,
Pubmed
,
Echinobase
Weintraub,
Activation of muscle-specific genes in pigment, nerve, fat, liver, and fibroblast cell lines by forced expression of MyoD.
1989,
Pubmed
Wessel,
Myosin heavy chain accumulates in dissimilar cell types of the macromere lineage in the sea urchin embryo.
1990,
Pubmed
,
Echinobase
White,
Defective somite patterning in mouse embryos with reduced levels of Tbx6.
2003,
Pubmed
Wu,
Twist is an essential regulator of the skeletogenic gene regulatory network in the sea urchin embryo.
2008,
Pubmed
,
Echinobase
Xu,
SOX9 and myocardin counteract each other in regulating vascular smooth muscle cell differentiation.
2012,
Pubmed
Yu,
MyoR is expressed in nonmyogenic cells and can inhibit their differentiation.
2003,
Pubmed
Zhang,
Expression of germline markers in three species of amphioxus supports a preformation mechanism of germ cell development in cephalochordates.
2013,
Pubmed
Zinzen,
Combinatorial binding predicts spatio-temporal cis-regulatory activity.
2009,
Pubmed
von Scheven,
Protein and genomic organisation of vertebrate MyoR and Capsulin genes and their expression during avian development.
2006,
Pubmed