scholarly journals Germ layer specific regulation of cell polarity and adhesion gives insight into the evolution of mesoderm

2017 ◽  
Author(s):  
Miguel Salinas-Saavedra ◽  
Amber Q. Rock ◽  
Mark Q Martindale
Keyword(s):  
Cell Adhesion ◽  
Cell Polarity ◽  
Ectopic Expression ◽  
Par Proteins ◽  
Adhesion System ◽  
Transcription Factor Genes ◽  
Epithelial Structure ◽  
Specific Mrnas ◽  
Specific Regulation ◽  
Insight Into

AbstractIn triploblastic animals, Par-proteins regulate cell-polarity and adherens junctions of both ectodermal and endodermal epithelia. But, in embryos of the diploblastic cnidarian Nematostella vectensis, Par-proteins are degraded in all cells in the bifunctional gastrodermal epithelium. Using immunohistochemistry, CRISPR/Cas9 mutagenesis, and overexpression of specific mRNAs, we describe the functional association between Par-proteins, ß-catenin, and snail transcription factor genes in N. vectensis embryos. We demonstrate that the aPKC/Par complex regulates the localization of ß-catenin in the ectoderm by stabilizing its role in cell-adhesion, and that endomesodermal epithelial cells are organized by a different cell-adhesion system than that of overlying ectoderm. We also show that ectopic expression of snail genes, which are expressed in mesodermal derivatives in bilaterians, are sufficient to downregulate Par-proteins and translocate ß-catenin from the junctions to the cytoplasm in ectodermal cells. These data provide molecular insight into the evolution of epithelial structure and distinct mesodermal tissue in metazoan embryos.

scholarly journals Germ layer-specific regulation of cell polarity and adhesion gives insight into the evolution of mesoderm

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Miguel Salinas-Saavedra ◽  
Amber Q Rock ◽  
Mark Q Martindale
Keyword(s):  
Cell Adhesion ◽  
Cell Polarity ◽  
Ectopic Expression ◽  
Par Proteins ◽  
Cell Behaviors ◽  
Cnidarian Nematostella Vectensis ◽  
Distinct Cell ◽  
Transcription Factor Genes ◽  
Specific Regulation ◽  
Insight Into

In triploblastic animals, Par-proteins regulate cell-polarity and adherens junctions of both ectodermal and endodermal epithelia. But, in embryos of the diploblastic cnidarian Nematostella vectensis, Par-proteins are degraded in all cells in the bifunctional gastrodermal epithelium. Using immunohistochemistry, CRISPR/Cas9 mutagenesis, and mRNA overexpression, we describe the functional association between Par-proteins, ß-catenin, and snail transcription factor genes in N. vectensis embryos. We demonstrate that the aPKC/Par complex regulates the localization of ß-catenin in the ectoderm by stabilizing its role in cell-adhesion, and that endomesodermal epithelial cells are organized by a different cell-adhesion system than overlying ectoderm. We also show that ectopic expression of snail genes, which are expressed in mesodermal derivatives in bilaterians, is sufficient to downregulate Par-proteins and translocate ß-catenin from the junctions to the cytoplasm in ectodermal cells. These data provide molecular insight into the evolution of epithelial structure and distinct cell behaviors in metazoan embryos.

scholarly journals Par protein localization during the early development of Mnemiopsis leidyi suggests different modes of epithelial organization in Metazoa

2018 ◽  
Author(s):  
Miguel Salinas-Saavedra ◽  
Mark Q Martindale
Keyword(s):  
Cell Adhesion ◽  
Cell Polarity ◽  
Protein Localization ◽  
Mnemiopsis Leidyi ◽  
Epithelial Tissue ◽  
Par Proteins ◽  
Pcp Signaling ◽  
Specific Mrnas ◽  
Junctional Complexes ◽  
Cell Cell

ABSTRACTIn bilaterians and cnidarians, embryonic and epithelial cell-polarity are regulated by the interactions between Par proteins, Wnt/PCP signaling pathway, and cell-cell adhesion. Par proteins are highly conserved across Metazoa, including ctenophores. But strikingly, ctenophore genomes lack components of the Wnt/PCP pathway and cell-cell adhesion complexes; raising the question if ctenophore cells are polarized by mechanisms involving Par proteins. Here, by using immunohistochemistry and live-cell imaging overexpression of specific mRNAs, we describe for the first time the subcellular localization of selected Par proteins in blastomeres and epithelial cells during the embryogenesis of the ctenophore Mnemiopsis leidyi. We show that these proteins distribute differently compared to what has been described for other animals, even though they segregate in a host-specific fashion when expressed in cnidarian embryos. This differential localization might be related to the emergence of different junctional complexes during metazoan evolution. Data obtained here challenge the ancestry of the apicobasal cell polarity and raise questions about the homology of epithelial tissue across the Metazoa.

scholarly journals Regulating polarity by directing traffic: Cdc42 prevents adherens junctions from Crumblin' aPart

2008 ◽  
Vol 183 (6) ◽  
pp. 971-974 ◽  
Author(s):  
Mara C. Duncan ◽  
Mark Peifer
Keyword(s):  
Cell Adhesion ◽  
Actin Cytoskeleton ◽  
Cell Polarity ◽  
Adherens Junctions ◽  
Vesicular Trafficking ◽  
Cell Junction ◽  
Par Proteins ◽  
Cell Biol ◽  
Embryonic Morphogenesis ◽  
Junction Proteins

The GTPase Cdc42 was among the original genes identified with roles in cell polarity, and interest in its cellular roles from yeast to humans remains high. Cdc42 is a well-known regulator of the actin cytoskeleton, but also plays important roles in vesicular trafficking. In this issue, Harris and Tepass (Harris, K.P, and U. Tepass. 2008. J. Cell. Biol. 183:1129–1143) provide new insights into how Cdc42 and Par proteins work together to modulate cell adhesion and polarity during embryonic morphogenesis by regulating the traffic of key cell junction proteins.

scholarly journals Par protein localization during the early development of Mnemiopsis leidyi suggests different modes of epithelial organization in the metazoa

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Miguel Salinas-Saavedra ◽  
Mark Q Martindale
Keyword(s):  
Cell Adhesion ◽  
Live Cell Imaging ◽  
Protein Localization ◽  
Mnemiopsis Leidyi ◽  
Par Proteins ◽  
Pcp Signaling ◽  
Specific Mrnas ◽  
Junctional Complexes ◽  
First Time ◽  
Cell Cell

In bilaterians and cnidarians, epithelial cell-polarity is regulated by the interactions between Par proteins, Wnt/PCP signaling pathway, and cell-cell adhesion. Par proteins are highly conserved across Metazoa, including ctenophores. But strikingly, ctenophore genomes lack components of the Wnt/PCP pathway and cell-cell adhesion complexes raising the question if ctenophore cells are polarized by mechanisms involving Par proteins. Here, by using immunohistochemistry and live-cell imaging of specific mRNAs, we describe for the first time the subcellular localization of selected Par proteins in blastomeres and epithelial cells during the embryogenesis of the ctenophore Mnemiopsis leidyi. We show that these proteins distribute differently compared to what has been described for other animals, even though they segregate in a host-specific fashion when expressed in cnidarian embryos. This differential localization might be related to the emergence of different junctional complexes during metazoan evolution.

Sign in / Sign up

Export Citation Format

Share Document