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In metazoans, the epithelial-mesenchymal transition (EMT) is a crucial process for placing the mesoderm beneath the ectoderm. Primary mesenchyme cells (PMCs) at the vegetal pole of the sea urchin embryo ingress into the floor of the blastocoele from the blastula epithelium and later become the skeletogenic mesenchyme. This ingression movement is a classic EMT during which the PMCs penetrate the basal lamina, lose adherens junctions and migrate into the blastocoele. Later, secondary mesenchyme cells (SMCs) also enter the blastocoele via an EMT, but they accompany the invagination of the archenteron initially, in much the same way vertebrate mesenchyme enters the embryo along with endoderm. Here we identify a sea urchin ortholog of the Snail transcription factor, and focus on its roles regulating EMT during PMC ingression. Functional knockdown analyses of Snail in whole embryos and chimeras demonstrate that Snail is required in micromeres for PMC ingression. Snail represses the transcription of cadherin, a repression that appears evolutionarily conserved throughout the animal kingdom. Furthermore, Snail expression is required for endocytosis of cadherin, a cellular activity that accompanies PMC ingression. Perturbation studies position Snail in the sea urchin micromere-PMC gene regulatory network (GRN), downstream of Pmar1 and Alx1, and upstream of several PMC-expressed proteins. Taken together, our findings indicate that Snail plays an essential role in PMCs to control the EMT process, in part through its repression of cadherin expression during PMC ingression, and in part through its role in the endocytosis that helps convert an epithelial cell to a mesenchyme cell.
Alberga,
The snail gene required for mesoderm formation in Drosophila is expressed dynamically in derivatives of all three germ layers.
1991, Pubmed
Alberga,
The snail gene required for mesoderm formation in Drosophila is expressed dynamically in derivatives of all three germ layers.
1991,
Pubmed Amore,
Spdeadringer, a sea urchin embryo gene required separately in skeletogenic and oral ectoderm gene regulatory networks.
2003,
Pubmed
,
Echinobase Angerer,
Patterning the sea urchin embryo: gene regulatory networks, signaling pathways, and cellular interactions.
2003,
Pubmed
,
Echinobase Barrallo-Gimeno,
The Snail genes as inducers of cell movement and survival: implications in development and cancer.
2005,
Pubmed Batlle,
The transcription factor snail is a repressor of E-cadherin gene expression in epithelial tumour cells.
2000,
Pubmed Bradham,
p38 MAPK is essential for secondary axis specification and patterning in sea urchin embryos.
2006,
Pubmed
,
Echinobase Brandhorst,
Molecular patterning along the sea urchin animal-vegetal axis.
2002,
Pubmed
,
Echinobase Cano,
The transcription factor snail controls epithelial-mesenchymal transitions by repressing E-cadherin expression.
2000,
Pubmed Carver,
The mouse snail gene encodes a key regulator of the epithelial-mesenchymal transition.
2001,
Pubmed Cavallaro,
Cell adhesion and signalling by cadherins and Ig-CAMs in cancer.
2004,
Pubmed Croce,
ske-T, a T-box gene expressed in the skeletogenic mesenchyme lineage of the sea urchin embryo.
2001,
Pubmed
,
Echinobase Davidson,
Specification of cell fate in the sea urchin embryo: summary and some proposed mechanisms.
1998,
Pubmed
,
Echinobase Davidson,
A provisional regulatory gene network for specification of endomesoderm in the sea urchin embryo.
2002,
Pubmed
,
Echinobase Davidson,
A genomic regulatory network for development.
2002,
Pubmed
,
Echinobase De Craene,
Unraveling signalling cascades for the Snail family of transcription factors.
2005,
Pubmed D'Souza-Schorey,
Disassembling adherens junctions: breaking up is hard to do.
2005,
Pubmed Emily-Fenouil,
GSK3beta/shaggy mediates patterning along the animal-vegetal axis of the sea urchin embryo.
1998,
Pubmed
,
Echinobase Ettensohn,
Alx1, a member of the Cart1/Alx3/Alx4 subfamily of Paired-class homeodomain proteins, is an essential component of the gene network controlling skeletogenic fate specification in the sea urchin embryo.
2003,
Pubmed
,
Echinobase Ettensohn,
Patterning the early sea urchin embryo.
2000,
Pubmed
,
Echinobase Fernandez-Serra,
Role of the ERK-mediated signaling pathway in mesenchyme formation and differentiation in the sea urchin embryo.
2004,
Pubmed
,
Echinobase Fink,
Three cell recognition changes accompany the ingression of sea urchin primary mesenchyme cells.
1985,
Pubmed
,
Echinobase Fuchikami,
T-brain homologue (HpTb) is involved in the archenteron induction signals of micromere descendant cells in the sea urchin embryo.
2002,
Pubmed
,
Echinobase Gross,
LvTbx2/3: a T-box family transcription factor involved in formation of the oral/aboral axis of the sea urchin embryo.
2003,
Pubmed
,
Echinobase Guss,
Skeletal morphogenesis in the sea urchin embryo: regulation of primary mesenchyme gene expression and skeletal rod growth by ectoderm-derived cues.
1997,
Pubmed
,
Echinobase Hardin,
A homologue of snail is expressed transiently in subsets of mesenchyme cells in the sea urchin embryo and is down-regulated in axis-deficient embryos.
2006,
Pubmed
,
Echinobase Hemavathy,
Snail/slug family of repressors: slowly going into the fast lane of development and cancer.
2000,
Pubmed Hertzler,
alphaSU2, an epithelial integrin that binds laminin in the sea urchin embryo.
1999,
Pubmed
,
Echinobase Ingersoll,
Characterization and expression of two matrix metalloproteinase genes during sea urchin development.
2005,
Pubmed
,
Echinobase Jamora,
A signaling pathway involving TGF-beta2 and snail in hair follicle morphogenesis.
2005,
Pubmed Janda,
Raf plus TGFbeta-dependent EMT is initiated by endocytosis and lysosomal degradation of E-cadherin.
2006,
Pubmed Jordà ,
Upregulation of MMP-9 in MDCK epithelial cell line in response to expression of the Snail transcription factor.
2005,
Pubmed Keller,
Mechanisms of convergence and extension by cell intercalation.
2000,
Pubmed Kurokawa,
HpEts, an ets-related transcription factor implicated in primary mesenchyme cell differentiation in the sea urchin embryo.
1999,
Pubmed
,
Echinobase Liu,
A role for rhoB in the delamination of neural crest cells from the dorsal neural tube.
1998,
Pubmed Logan,
Nuclear beta-catenin is required to specify vegetal cell fates in the sea urchin embryo.
1999,
Pubmed
,
Echinobase Lu,
Downregulation of caveolin-1 function by EGF leads to the loss of E-cadherin, increased transcriptional activity of beta-catenin, and enhanced tumor cell invasion.
2003,
Pubmed Miller,
Changes in the pattern of adherens junction-associated beta-catenin accompany morphogenesis in the sea urchin embryo.
1997,
Pubmed
,
Echinobase Miller,
Characterization of the role of cadherin in regulating cell adhesion during sea urchin development.
1997,
Pubmed
,
Echinobase Miyoshi,
Snail and SIP1 increase cancer invasion by upregulating MMP family in hepatocellular carcinoma cells.
2004,
Pubmed Nieto,
Control of cell behavior during vertebrate development by Slug, a zinc finger gene.
1994,
Pubmed Nieto,
The snail superfamily of zinc-finger transcription factors.
2002,
Pubmed Oda,
Dynamic behavior of the cadherin-based cell-cell adhesion system during Drosophila gastrulation.
1998,
Pubmed Oliveri,
A regulatory gene network that directs micromere specification in the sea urchin embryo.
2002,
Pubmed
,
Echinobase Oliveri,
Activation of pmar1 controls specification of micromeres in the sea urchin embryo.
2003,
Pubmed
,
Echinobase Otim,
SpHnf6, a transcription factor that executes multiple functions in sea urchin embryogenesis.
2004,
Pubmed
,
Echinobase Perl,
A causal role for E-cadherin in the transition from adenoma to carcinoma.
1998,
Pubmed Ransick,
A complete second gut induced by transplanted micromeres in the sea urchin embryo.
1993,
Pubmed
,
Echinobase Röttinger,
A Raf/MEK/ERK signaling pathway is required for development of the sea urchin embryo micromere lineage through phosphorylation of the transcription factor Ets.
2004,
Pubmed
,
Echinobase Savagner,
Developmental transcription factor slug is required for effective re-epithelialization by adult keratinocytes.
2005,
Pubmed Shook,
Mechanisms, mechanics and function of epithelial-mesenchymal transitions in early development.
2003,
Pubmed
,
Echinobase Solursh,
Migration of sea urchin primary mesenchyme cells.
1986,
Pubmed
,
Echinobase Thiery,
Epithelial-mesenchymal transitions in tumour progression.
2002,
Pubmed Wikramanayake,
beta-Catenin is essential for patterning the maternally specified animal-vegetal axis in the sea urchin embryo.
1998,
Pubmed
,
Echinobase Yamashita,
Zinc transporter LIVI controls epithelial-mesenchymal transition in zebrafish gastrula organizer.
2004,
Pubmed Yokoyama,
Increased invasion and matrix metalloproteinase-2 expression by Snail-induced mesenchymal transition in squamous cell carcinomas.
2003,
Pubmed Zohn,
p38 and a p38-interacting protein are critical for downregulation of E-cadherin during mouse gastrulation.
2006,
Pubmed
