251
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Moroishi T, Park HW, Qin B, Chen Q, Meng Z, Plouffe SW, Taniguchi K, Yu FX, Karin M, Pan D, Guan KL. A YAP/TAZ-induced feedback mechanism regulates Hippo pathway homeostasis. Genes Dev 2015; 29:1271-84. [PMID: 26109050 PMCID: PMC4495398 DOI: 10.1101/gad.262816.115] [Citation(s) in RCA: 256] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, Moroishi et al. show that YAP and TAZ activation induces the negative regulators LATS1 kinase and LATS2 kinase to constitute a negative feedback mechanism to control YAP/TAZ activation duration and cellular response. This study provides new insights into the dynamic regulation and maintenance of Hippo pathway homeostasis. YAP (Yes-associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif) are major downstream effectors of the Hippo pathway that influences tissue homeostasis, organ size, and cancer development. Aberrant hyperactivation of YAP/TAZ causes tissue overgrowth and tumorigenesis, whereas their inactivation impairs tissue development and regeneration. Dynamic and precise control of YAP/TAZ activity is thus important to ensure proper physiological regulation and homeostasis of the cells. Here, we show that YAP/TAZ activation results in activation of their negative regulators, LATS1/2 (large tumor suppressor 1/2) kinases, to constitute a negative feedback loop of the Hippo pathway in both cultured cells and mouse tissues. YAP/TAZ in complex with the transcription factor TEAD (TEA domain family member) directly induce LATS2 expression. Furthermore, YAP/TAZ also stimulate the kinase activity of LATS1/2 through inducing NF2 (neurofibromin 2). This feedback regulation is responsible for the transient activation of YAP upon lysophosphatidic acid (LPA) stimulation and the inhibition of YAP-induced cell migration. Thus, this LATS-mediated feedback loop provides an efficient mechanism to establish the robustness and homeostasis of YAP/TAZ regulation.
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Affiliation(s)
- Toshiro Moroishi
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Hyun Woo Park
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Baodong Qin
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA; Department of Laboratory Medicine, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
| | - Qian Chen
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Zhipeng Meng
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Steven W Plouffe
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Koji Taniguchi
- Department of Pharmacology, University of California at San Diego, La Jolla, California 92093, USA; Department of Pathology, University of California at San Diego, La Jolla, California 92093, USA
| | - Fa-Xing Yu
- Children's Hospital, Fudan University, Shanghai 200032, China; Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Michael Karin
- Department of Pharmacology, University of California at San Diego, La Jolla, California 92093, USA; Department of Pathology, University of California at San Diego, La Jolla, California 92093, USA
| | - Duojia Pan
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Kun-Liang Guan
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
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252
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Agarwala S, Duquesne S, Liu K, Boehm A, Grimm L, Link S, König S, Eimer S, Ronneberger O, Lecaudey V. Amotl2a interacts with the Hippo effector Yap1 and the Wnt/β-catenin effector Lef1 to control tissue size in zebrafish. eLife 2015; 4:e08201. [PMID: 26335201 PMCID: PMC4596637 DOI: 10.7554/elife.08201] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Accepted: 09/02/2015] [Indexed: 12/17/2022] Open
Abstract
During development, proliferation must be tightly controlled for organs to reach their appropriate size. While the Hippo signaling pathway plays a major role in organ growth control, how it senses and responds to increased cell density is still unclear. In this study, we use the zebrafish lateral line primordium (LLP), a group of migrating epithelial cells that form sensory organs, to understand how tissue growth is controlled during organ formation. Loss of the cell junction-associated Motin protein Amotl2a leads to overproliferation and bigger LLP, affecting the final pattern of sensory organs. Amotl2a function in the LLP is mediated together by the Hippo pathway effector Yap1 and the Wnt/β-catenin effector Lef1. Our results implicate for the first time the Hippo pathway in size regulation in the LL system. We further provide evidence that the Hippo/Motin interaction is essential to limit tissue size during development. DOI:http://dx.doi.org/10.7554/eLife.08201.001 How do organs and tissues know when to stop growing? A cell communication pathway known as Hippo signaling plays a central role as it can tell cells to stop dividing. It is activated when cells in developing tissues come into contact with each other and causes a protein called Yap1 to be modified, which prevents it from entering the cell nucleus to activate genes that are involved in cell division. In a zebrafish embryo, an organ called the lateral line forms from a cluster of cells that migrate along the embryo's length. At regular intervals, the cluster deposits small bunches of cells from its trailing end. The resulting loss of cells from the cluster is balanced by cell division at the front of the cluster, which is triggered by another signaling pathway called Wnt signaling. A protein of the ‘Motin’ family called Amotl2a is present in this migrating cluster. Motin proteins form junctions between cells and inhibit the activity of Yap1, but it is not known whether they are involved in regulating the size of organs. Here, Agarwala et al. used the lateral line as a model to study the control of organ size in zebrafish embryos. The experiments show that when Amotl2a is absent, the migrating cell cluster becomes larger, with the highest levels of cell division occurring at its trailing end. Yap1 and a protein involved in Wnt signaling called Lef1 are also present in the cluster and are required for it to be normal in size. In zebrafish that lack Amotl2a, the additional loss of Yap1 prevents this cluster from becoming too large. From these and other results, it appears that Amotl2a regulates the size of the lateral line cell cluster by restricting the ability of Yap1 and Lef1 to promote cell division. Agarwala et al.'s findings demonstrate a role for Amotl2a in controlling the size of organs. A future challenge is to understand the details of how it restricts the activities of Yap1 and Lef1. DOI:http://dx.doi.org/10.7554/eLife.08201.002
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Affiliation(s)
- Sobhika Agarwala
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Developmental Biology, Institute for Biology I, Faculty of Biology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Sandra Duquesne
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Developmental Biology, Institute for Biology I, Faculty of Biology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Kun Liu
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Image Analysis Lab, Institute for Computer Science, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Anton Boehm
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Image Analysis Lab, Institute for Computer Science, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Lin Grimm
- Developmental Biology, Institute for Biology I, Faculty of Biology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Sandra Link
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Developmental Biology, Institute for Biology I, Faculty of Biology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Sabine König
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Stefan Eimer
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,ZBSA Center for Biological Systems Analysis, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Olaf Ronneberger
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany.,Image Analysis Lab, Institute for Computer Science, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
| | - Virginie Lecaudey
- Developmental Biology, Institute for Biology I, Faculty of Biology, Albert Ludwigs University of Freiburg, Freiburg im Breisgau, Germany
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253
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Abstract
Cadherin-catenin complexes are critical for the assembly of cell-cell adhesion structures known as adherens junctions. In addition to the mechanical linkage of neighboring cells to each other, these cell-cell adhesion protein complexes have recently emerged as important sensors and transmitters of the extracellular cues inside the cell body and into the nucleus. In the past few years, multiple studies have identified a connection between the cadherin-catenin protein complexes and major intracellular signaling pathways. Those studies are the main focus of this review.
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Affiliation(s)
- Olga Klezovitch
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Valeri Vasioukhin
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA ; Department of Pathology, University of Washington, Seattle, WA, 98195, USA ; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98195, USA
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254
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Denicol AC, Leão BCS, Dobbs KB, Mingoti GZ, Hansen PJ. Influence of Sex on Basal and Dickkopf-1 Regulated Gene Expression in the Bovine Morula. PLoS One 2015. [PMID: 26196299 PMCID: PMC4510475 DOI: 10.1371/journal.pone.0133587] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Sex affects function of the developing mammalian embryo as early as the preimplantation period. There were two goals of the current objective. The first was to determine the degree and nature of differences in gene expression between female and male embryos in the cow at the morula stage of development. The second objective was to determine whether DKK1, a molecule known to alter differentiation of the blastocyst, would affect gene expression differently for female and male morulae. In Experiment 1, female and male embryos were treated with DKK1 at Day 5 after insemination. Morulae were harvested 24 h after treatment, pooled in groups of 20 for microarray analysis and RNA subjected to analysis of gene expression by microarray hybridization. There were 662 differentially expressed genes between females and males and 128 of these genes had a fold change ≥ 1.5 between the two sexes. Of the genes upregulated in females, 49.5% were located in the X chromosome. Functional analysis predicted that cell survival was greater in female embryos. Experiment 2 involved a similar design except that transcripts for 12 genes previously reported to be affected by sex, DKK1 or the interaction were quantified by quantitative polymerase chain reaction. Expression of all genes tested that were affected by sex in experiment 1 was affected in a similar manner in Experiment 2. In contrast, effects of DKK1 on gene expression were largely not repeatable in Experiment 2. The exception was for the Hippo signaling gene AMOT, which was inhibited by DKK1. In Experiment 3, embryos produced by fertilization with unsorted sperm were treated with DKK1 at Day 5 and abundance of transcripts for CDX2, GATA6, and NANOG determined at Days 5, 6 and 7 after insemination. There was no effect of DKK1 on expression of any of the three genes. In conclusion, female and male bovine embryos have a different pattern of gene expression as early as the morula stage, and this is due to a large extent to expression of genes in the X chromosomes in females. Differential gene expression between female and male embryos is likely the basis for increased resistance to cell death signals in female embryos and disparity in responses of female and male embryos to changes in the maternal environment.
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Affiliation(s)
- Anna C Denicol
- Department of Animal Sciences, D.H. Barron Reproductive and Perinatal Biology Research Program, and Genetics Institute, University of Florida, Gainesville, Florida, United States of America
| | - Beatriz C S Leão
- Laboratory of Physiology of Reproduction, School of Veterinary Medicine, Universidade Estadual Paulista-UNESP, Araçatuba, SP, Brazil
| | - Kyle B Dobbs
- Department of Animal Sciences, D.H. Barron Reproductive and Perinatal Biology Research Program, and Genetics Institute, University of Florida, Gainesville, Florida, United States of America
| | - Gisele Z Mingoti
- Laboratory of Physiology of Reproduction, School of Veterinary Medicine, Universidade Estadual Paulista-UNESP, Araçatuba, SP, Brazil
| | - Peter J Hansen
- Department of Animal Sciences, D.H. Barron Reproductive and Perinatal Biology Research Program, and Genetics Institute, University of Florida, Gainesville, Florida, United States of America
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255
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Single cells get together: High-resolution approaches to study the dynamics of early mouse development. Semin Cell Dev Biol 2015; 47-48:92-100. [PMID: 26183190 DOI: 10.1016/j.semcdb.2015.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/17/2015] [Accepted: 06/19/2015] [Indexed: 11/22/2022]
Abstract
Embryonic development is a complex and highly dynamic process during which individual cells interact with one another, adopt different identities and organize themselves in three-dimensional space to generate an entire organism. Recent technical developments in genomics and high-resolution quantitative imaging are making it possible to study cellular populations at single-cell resolution and begin to integrate different inputs, for example genetic, physical and chemical factors, that affect cell differentiation over spatial and temporal scales. The preimplantation mouse embryo allows the analysis of cell fate decisions in vivo with high spatiotemporal resolution. In this review we highlight how the application of live imaging and single-cell resolution analysis pipelines is providing an unprecedented level of insight on the processes that shape the earliest stages of mammalian development.
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256
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Li-Villarreal N, Forbes MM, Loza AJ, Chen J, Ma T, Helde K, Moens CB, Shin J, Sawada A, Hindes AE, Dubrulle J, Schier AF, Longmore GD, Marlow FL, Solnica-Krezel L. Dachsous1b cadherin regulates actin and microtubule cytoskeleton during early zebrafish embryogenesis. Development 2015; 142:2704-18. [PMID: 26160902 DOI: 10.1242/dev.119800] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 06/25/2015] [Indexed: 01/04/2023]
Abstract
Dachsous (Dchs), an atypical cadherin, is an evolutionarily conserved regulator of planar cell polarity, tissue size and cell adhesion. In humans, DCHS1 mutations cause pleiotropic Van Maldergem syndrome. Here, we report that mutations in zebrafish dchs1b and dchs2 disrupt several aspects of embryogenesis, including gastrulation. Unexpectedly, maternal zygotic (MZ) dchs1b mutants show defects in the earliest developmental stage, egg activation, including abnormal cortical granule exocytosis (CGE), cytoplasmic segregation, cleavages and maternal mRNA translocation, in transcriptionally quiescent embryos. Later, MZdchs1b mutants exhibit altered dorsal organizer and mesendodermal gene expression, due to impaired dorsal determinant transport and Nodal signaling. Mechanistically, MZdchs1b phenotypes can be explained in part by defective actin or microtubule networks, which appear bundled in mutants. Accordingly, disruption of actin cytoskeleton in wild-type embryos phenocopied MZdchs1b mutant defects in cytoplasmic segregation and CGE, whereas interfering with microtubules in wild-type embryos impaired dorsal organizer and mesodermal gene expression without perceptible earlier phenotypes. Moreover, the bundled microtubule phenotype was partially rescued by expressing either full-length Dchs1b or its intracellular domain, suggesting that Dchs1b affects microtubules and some developmental processes independent of its known ligand Fat. Our results indicate novel roles for vertebrate Dchs in actin and microtubule cytoskeleton regulation in the unanticipated context of the single-celled embryo.
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Affiliation(s)
- Nanbing Li-Villarreal
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Meredyth M Forbes
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461, USA
| | - Andrew J Loza
- Department of Internal Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Jiakun Chen
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Taylur Ma
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Kathryn Helde
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Cecilia B Moens
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Jimann Shin
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Atsushi Sawada
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Anna E Hindes
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Julien Dubrulle
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Alexander F Schier
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Gregory D Longmore
- Department of Internal Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
| | - Florence L Marlow
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461, USA Department of Neuroscience, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461, USA
| | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
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257
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Parfitt DE, Shen MM. From blastocyst to gastrula: gene regulatory networks of embryonic stem cells and early mouse embryogenesis. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0542. [PMID: 25349451 DOI: 10.1098/rstb.2013.0542] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
To date, many regulatory genes and signalling events coordinating mammalian development from blastocyst to gastrulation stages have been identified by mutational analyses and reverse-genetic approaches, typically on a gene-by-gene basis. More recent studies have applied bioinformatic approaches to generate regulatory network models of gene interactions on a genome-wide scale. Such models have provided insights into the gene networks regulating pluripotency in embryonic and epiblast stem cells, as well as cell-lineage determination in vivo. Here, we review how regulatory networks constructed for different stem cell types relate to corresponding networks in vivo and provide insights into understanding the molecular regulation of the blastocyst-gastrula transition.
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Affiliation(s)
- David-Emlyn Parfitt
- Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Urology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Systems Biology, Herbert Irving Comprehensive Cancer Center, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | - Michael M Shen
- Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Urology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA Department of Systems Biology, Herbert Irving Comprehensive Cancer Center, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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258
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Abstract
Formation of a eutherian mammal requires concurrent establishment of embryonic and extraembryonic lineages. The functions of the trophectoderm and primitive endoderm are to enable implantation in the maternal uterus, axis specification and delivery of nutrients. The pluripotent epiblast represents the founding cell population of the embryo proper, which is protected from ectopic and premature differentiation until it is required to respond to inductive cues to form the fetus. While positional information plays a major role in specifying the trophoblast lineage, segregation of primitive endoderm from epiblast depends upon gradual acquisition of transcriptional identity, directed but not initiated by fibroblast growth factor (FGF) signalling. Following early cleavage divisions and formation of the blastocyst, cells of the inner cell mass lose totipotency. Developing epiblast cells transiently attain the state of naive pluripotency and competence to self-renew in vitro as embryonic stem cells and in vivo by means of diapause. This property is lost after implantation as the epiblast epithelializes and becomes primed in preparation for gastrulation and subsequent organogenesis.
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Affiliation(s)
- Thorsten Boroviak
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Jennifer Nichols
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
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259
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Bedzhov I, Graham SJL, Leung CY, Zernicka-Goetz M. Developmental plasticity, cell fate specification and morphogenesis in the early mouse embryo. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0538. [PMID: 25349447 PMCID: PMC4216461 DOI: 10.1098/rstb.2013.0538] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
A critical point in mammalian development is when the early embryo implants into its mother's uterus. This event has historically been difficult to study due to the fact that it occurs within the maternal tissue and therefore is hidden from view. In this review, we discuss how the mouse embryo is prepared for implantation and the molecular mechanisms involved in directing and coordinating this crucial event. Prior to implantation, the cells of the embryo are specified as precursors of future embryonic and extra-embryonic lineages. These preimplantation cell fate decisions rely on a combination of factors including cell polarity, position and cell–cell signalling and are influenced by the heterogeneity between early embryo cells. At the point of implantation, signalling events between the embryo and mother, and between the embryonic and extraembryonic compartments of the embryo itself, orchestrate a total reorganization of the embryo, coupled with a burst of cell proliferation. New developments in embryo culture and imaging techniques have recently revealed the growth and morphogenesis of the embryo at the time of implantation, leading to a new model for the blastocyst to egg cylinder transition. In this model, pluripotent cells that will give rise to the fetus self-organize into a polarized three-dimensional rosette-like structure that initiates egg cylinder formation.
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Affiliation(s)
- Ivan Bedzhov
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Sarah J L Graham
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Chuen Yan Leung
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Magdalena Zernicka-Goetz
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
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260
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Li Y, Zhou H, Li F, Chan SW, Lin Z, Wei Z, Yang Z, Guo F, Lim CJ, Xing W, Shen Y, Hong W, Long J, Zhang M. Angiomotin binding-induced activation of Merlin/NF2 in the Hippo pathway. Cell Res 2015; 25:801-17. [PMID: 26045165 PMCID: PMC4493278 DOI: 10.1038/cr.2015.69] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 05/08/2015] [Accepted: 05/11/2015] [Indexed: 12/18/2022] Open
Abstract
The tumor suppressor Merlin/NF2 functions upstream of the core Hippo pathway kinases Lats1/2 and Mst1/2, as well as the nuclear E3 ubiquitin ligase CRL4(DCAF1). Numerous mutations of Merlin have been identified in Neurofibromatosis type 2 and other cancer patients. Despite more than two decades of research, the upstream regulator of Merlin in the Hippo pathway remains unknown. Here we show by high-resolution crystal structures that the Lats1/2-binding site on the Merlin FERM domain is physically blocked by Merlin's auto-inhibitory tail. Angiomotin binding releases the auto-inhibition and promotes Merlin's binding to Lats1/2. Phosphorylation of Ser518 outside the Merlin's auto-inhibitory tail does not obviously alter Merlin's conformation, but instead prevents angiomotin from binding and thus inhibits Hippo pathway kinase activation. Cancer-causing mutations clustered in the angiomotin-binding domain impair angiomotin-mediated Merlin activation. Our findings reveal that angiomotin and Merlin respectively interface cortical actin filaments and core kinases in Hippo signaling, and allow construction of a complete Hippo signaling pathway.
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Affiliation(s)
- Youjun Li
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong, China
| | - Hao Zhou
- 1] State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin 300071, China [2] College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Fengzhi Li
- 1] State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin 300071, China [2] College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Siew Wee Chan
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), 61, Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Zhijie Lin
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong, China
| | - Zhiyi Wei
- 1] Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong, China [2] Department of Biology, South University of Science and Technology of China, Shenzhen, Guangdong 518055, China
| | - Zhou Yang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong, China
| | - Fusheng Guo
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), 61, Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Chun Jye Lim
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), 61, Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Wancai Xing
- 1] State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin 300071, China [2] College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Yuequan Shen
- 1] State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin 300071, China [2] College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Wanjin Hong
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), 61, Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Jiafu Long
- 1] State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin 300071, China [2] College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Mingjie Zhang
- 1] Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong, China [2] Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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261
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Hansen CG, Moroishi T, Guan KL. YAP and TAZ: a nexus for Hippo signaling and beyond. Trends Cell Biol 2015; 25:499-513. [PMID: 26045258 DOI: 10.1016/j.tcb.2015.05.002] [Citation(s) in RCA: 412] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 05/02/2015] [Accepted: 05/05/2015] [Indexed: 02/06/2023]
Abstract
The Hippo pathway is a potent regulator of cellular proliferation, differentiation, and tissue homeostasis. Here we review the regulatory mechanisms of the Hippo pathway and discuss the function of Yes-associated protein (YAP)/transcriptional coactivator with a PDZ-binding domain (TAZ), the prime mediators of the Hippo pathway, in stem cell biology and tissue regeneration. We highlight their activities in both the nucleus and the cytoplasm and discuss their role as a signaling nexus and integrator of several other prominent signaling pathways such as the Wnt, G protein-coupled receptor (GPCR), epidermal growth factor (EGF), bone morphogenetic protein (BMP)/transforming growth factor beta (TGFβ), and Notch pathways.
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Affiliation(s)
- Carsten Gram Hansen
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA.,Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Toshiro Moroishi
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA.,Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kun-Liang Guan
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA.,Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
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262
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Frum T, Ralston A. Cell signaling and transcription factors regulating cell fate during formation of the mouse blastocyst. Trends Genet 2015; 31:402-10. [PMID: 25999217 DOI: 10.1016/j.tig.2015.04.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/05/2015] [Accepted: 04/07/2015] [Indexed: 11/17/2022]
Abstract
The first cell fate decisions during mammalian development establish tissues essential for healthy pregnancy. The mouse has served as a valuable model for discovering pathways regulating the first cell fate decisions because of the ease with which early embryos can be recovered and the availability of an arsenal of classical and emerging methods for manipulating gene expression. We summarize the major pathways that govern the first cell fate decisions in mouse development. This knowledge serves as a paradigm for exploring how emergent properties of a self-organizing system can dynamically regulate gene expression and cell fate plasticity. Moreover, it brings to light the processes that establish healthy pregnancy and ES cells. We also describe unsolved mysteries and new technologies that could help to overcome experimental challenges in the field.
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Affiliation(s)
- Tristan Frum
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Amy Ralston
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
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263
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Sasaki H. Position- and polarity-dependent Hippo signaling regulates cell fates in preimplantation mouse embryos. Semin Cell Dev Biol 2015; 47-48:80-7. [PMID: 25986053 DOI: 10.1016/j.semcdb.2015.05.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/08/2015] [Accepted: 05/08/2015] [Indexed: 11/25/2022]
Abstract
During the preimplantation stage, mouse embryos establish two cell lineages by the time of early blastocyst formation: the trophectoderm (TE) and the inner cell mass (ICM). Historical models have proposed that the establishment of these two lineages depends on the cell position within the embryo (e.g., the positional model) or cell polarization along the apicobasal axis (e.g., the polarity model). Recent findings have revealed that the Hippo signaling pathway plays a central role in the cell fate-specification process: active and inactive Hippo signaling in the inner and outer cells promote ICM and TE fates, respectively. Intercellular adhesion activates, while apicobasal polarization suppresses Hippo signaling, and a combination of these processes determines the spatially regulated activation of the Hippo pathway in 32-cell-stage embryos. Therefore, there is experimental evidence in favor of both positional and polarity models. At the molecular level, phosphorylation of the Hippo-pathway component angiomotin at adherens junctions (AJs) in the inner (apolar) cells activates the Lats protein kinase and triggers Hippo signaling. In the outer cells, however, cell polarization sequesters Amot from basolateral AJs and suppresses activation of the Hippo pathway. Other mechanisms, including asymmetric cell division and Notch signaling, also play important roles in the regulation of embryonic development. In this review, I discuss how these mechanisms cooperate with the Hippo signaling pathway during cell fate-specification processes.
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Affiliation(s)
- Hiroshi Sasaki
- Laboratory for Embryogenesis, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
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264
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Lorthongpanich C, Issaragrisil S. Emerging Role of the Hippo Signaling Pathway in Position Sensing and Lineage Specification in Mammalian Preimplantation Embryos. Biol Reprod 2015; 92:143. [PMID: 25947059 DOI: 10.1095/biolreprod.114.127803] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 04/29/2015] [Indexed: 12/29/2022] Open
Abstract
In preimplantation mouse embryos, the first lineage differentiation takes place in the 8- to 16-cell-stage embryo and results in formation of the trophectoderm (TE) and inner cell mass (ICM), which will give rise to the trophoblast of the placenta and the embryo proper, respectively. Although, it is widely accepted that positioning of a cell within the embryo influences lineage differentiation, the mechanism underlying differential lineage differentiation and how it involves cell position are largely unknown. Interestingly, novel cues from the Hippo pathway have been recently demonstrated in the preimplantation mouse embryo. Unlike the mechanisms reported from epithelium-cultured cells, the Hippo pathway was found to be responsible for translating positional information to lineage specification through a position-sensing mechanism. Disruption of Hippo pathway-component genes in early embryos results in failure of lineage specification and failure of postimplantation development. In this review, we discuss the unique role of the Hippo signaling pathway in early embryo development and its role in lineage specification. Understanding the activity and regulation of the Hippo pathway may offer new insights into other areas of developmental biology that evolve from understanding of this cell-fate specification in the early embryonic cell.
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Affiliation(s)
- Chanchao Lorthongpanich
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Surapol Issaragrisil
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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265
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Cao Z, Carey TS, Ganguly A, Wilson CA, Paul S, Knott JG. Transcription factor AP-2γ induces early Cdx2 expression and represses HIPPO signaling to specify the trophectoderm lineage. Development 2015; 142:1606-15. [PMID: 25858457 DOI: 10.1242/dev.120238] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/06/2015] [Indexed: 01/31/2023]
Abstract
Cell fate decisions are fundamental to the development of multicellular organisms. In mammals the first cell fate decision involves segregation of the pluripotent inner cell mass and the trophectoderm, a process regulated by cell polarity proteins, HIPPO signaling and lineage-specific transcription factors such as CDX2. However, the regulatory mechanisms that operate upstream to specify the trophectoderm lineage have not been established. Here we report that transcription factor AP-2γ (TFAP2C) functions as a novel upstream regulator of Cdx2 expression and position-dependent HIPPO signaling in mice. Loss- and gain-of-function studies and promoter analysis revealed that TFAP2C binding to an intronic enhancer is required for activation of Cdx2 expression during early development. During the 8-cell to morula transition TFAP2C potentiates cell polarity to suppress HIPPO signaling in the outside blastomeres. TFAP2C depletion triggered downregulation of PARD6B, loss of apical cell polarity, disorganization of F-actin, and activation of HIPPO signaling in the outside blastomeres. Rescue experiments using Pard6b mRNA restored cell polarity but only partially corrected position-dependent HIPPO signaling, suggesting that TFAP2C negatively regulates HIPPO signaling via multiple pathways. Several genes involved in regulation of the actin cytoskeleton (including Rock1, Rock2) were downregulated in TFAP2C-depleted embryos. Inhibition of ROCK1 and ROCK2 activity during the 8-cell to morula transition phenocopied TFAP2C knockdown, triggering a loss of position-dependent HIPPO signaling and decrease in Cdx2 expression. Altogether, these results demonstrate that TFAP2C facilitates trophectoderm lineage specification by functioning as a key regulator of Cdx2 transcription, cell polarity and position-dependent HIPPO signaling.
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Affiliation(s)
- Zubing Cao
- Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA
| | - Timothy S Carey
- Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA
| | - Avishek Ganguly
- Department of Pathology and Laboratory Medicine, Institute of Reproductive Health and Regenerative Medicine, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Catherine A Wilson
- Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA
| | - Soumen Paul
- Department of Pathology and Laboratory Medicine, Institute of Reproductive Health and Regenerative Medicine, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Jason G Knott
- Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University, East Lansing, MI 48824, USA
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266
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Abstract
Lessons learned from conserved vertebrate developmental pathways have catalyzed rapid advances in pluripotent stem cell differentiation towards therapeutically relevant cell types. The most highly conserved phases of development are associated with the early patterning of the body plan - the so-called phylotypic stage. Both prior to and after this stage there is much more divergence across species. Developmental differences between human and mouse at the blastocyst and early post-implantation stages might help explain the differences among the different stem cell lines derived from these embryos. A better understanding of these early stages of human development will aid our ability to generate and manipulate human stem cells and their derivatives.
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Affiliation(s)
- Janet Rossant
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, Ontario, Canada M5G OA4 Department of Molecular Genetics, University of Toronto, Peter Gilgan Centre for Research and Learning, 686 Bay Street, Toronto, Ontario, Canada M5G OA4
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267
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Abstract
The early mouse embryo is an excellent system to study how a small group of initially rounded cells start to change shape and establish the first forms of adhesion-based cell-cell interactions in mammals in vivo. In addition to its critical role in the structural integrity of the embryo, we discuss here how adhesion is important to regulate cell polarity and cell fate. Recent evidence suggests that adherens junctions participate in signaling pathways by localizing key proteins to subcellular microdomains. E-cadherin has been identified as the main player required for the establishment of adhesion but other mechanisms involving additional proteins or physical forces acting in the embryo may also contribute. Application of new technologies that enable high-resolution quantitative imaging of adhesion protein dynamics and measurements of biomechanical forces will provide a greater understanding of how adhesion patterns the early mammalian embryo.
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Affiliation(s)
- Melanie D White
- European Molecular Biology Laboratory (EMBL) Australia, Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Nicolas Plachta
- European Molecular Biology Laboratory (EMBL) Australia, Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
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268
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Affiliation(s)
- Fa-Xing Yu
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, California 92093;
- Children's Hospital and Institute of Biomedical Sciences, Fudan University, Shanghai, China 200032
| | - Zhipeng Meng
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, California 92093;
| | - Steven W. Plouffe
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, California 92093;
| | - Kun-Liang Guan
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, California 92093;
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269
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Liu S, Bou G, Sun R, Guo S, Xue B, Wei R, Cooney AJ, Liu Z. Sox2 is the faithful marker for pluripotency in pig: evidence from embryonic studies. Dev Dyn 2015; 244:619-27. [PMID: 25619399 DOI: 10.1002/dvdy.24248] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 12/25/2014] [Accepted: 12/26/2014] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Mammalian first lineage segregation generates trophectoderm (TE) and pluripotent inner cell mass (ICM), which provides an ideal model for studying the mechanisms of maintenance and loss of pluripotency. In mouse, the transcription factor OCT4 restricts to ICM and plays a key role in TE/ICM specification and pluripotent regulatory networks. However, in pig, OCT4 does not restrict to ICM cells, suggesting a different molecular basis in TE/ICM specification and pluripotent regulatory networks. RESULTS To explore molecular basis of porcine TE/ICM specification and pluripotent regulatory networks, we examined expression pattern of pluripotency factors, including SOX2, REX1, SALL4, ESG1, NANOG, TBX3, LIN28, KLF2, and KLF5, in porcine blastocysts. We found that SOX2 is a faithful pluripotent marker that anchored to the pluripotent cells including embryonic part cells, ICM cells and newly EPI cells along with developmental progress, whereas OCT4 expressed in almost all the cells at the same time. Consistently, analysis of spatiotemporal distribution of SOX2 and the TE marker CDX2 revealed an exclusive expression pattern in D6 blastocysts, whereas no correlation was observed between OCT4 and CDX2 at the same stage. CONCLUSIONS Our results provide a molecular basis in porcine embryonic patterning and a clue for further studying porcine pluripotent regulatory networks.
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Affiliation(s)
- Shichao Liu
- College of life science, Northeast Agricultural University of China, Harbin, China
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270
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Krawchuk D, Anani S, Honma-Yamanaka N, Polito S, Shafik M, Yamanaka Y. Loss of LKB1 leads to impaired epithelial integrity and cell extrusion in the early mouse embryo. J Cell Sci 2015; 128:1011-22. [PMID: 25588837 DOI: 10.1242/jcs.162156] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
LKB1/PAR-4 is essential for the earliest polarization steps in Caenorhabditis elegans embryos and Drosophila oocytes. Although LKB1 (also known as STK11) is sufficient to initiate polarity in a single mammalian intestinal epithelial cell, its necessity in the formation and maintenance of mammalian epithelia remains unclear. To address this, we completely remove LKB1 from mouse embryos by generating maternal-zygotic Lkb1 mutants and find that it is dispensable for polarity and epithelia formation in the early embryo. Instead, loss of Lkb1 leads to the extrusion of cells from blastocyst epithelia that remain alive and can continue to divide. Chimeric analysis shows that Lkb1 is cell-autonomously required to prevent these extrusions. Furthermore, heterozygous loss of Cdh1 exacerbates the number of extrusions per blastocyst, suggesting that LKB1 has a role in regulating adherens junctions in order to prevent extrusion in epithelia.
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Affiliation(s)
- Dayana Krawchuk
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
| | - Shihadeh Anani
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada Department of Human Genetics, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
| | - Nobuko Honma-Yamanaka
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
| | - Samantha Polito
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
| | - Marian Shafik
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
| | - Yojiro Yamanaka
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada Department of Human Genetics, McGill University, 1160 Pine Avenue West, Room 419, Montréal, QC H3A 1A3, Canada
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271
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Kodaka M, Hata Y. The mammalian Hippo pathway: regulation and function of YAP1 and TAZ. Cell Mol Life Sci 2015; 72:285-306. [PMID: 25266986 PMCID: PMC11113917 DOI: 10.1007/s00018-014-1742-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/08/2014] [Accepted: 09/25/2014] [Indexed: 02/07/2023]
Abstract
The Hippo pathway was originally identified as the signaling that controls organ size in Drosophila, with the core architecture conserved in mammals. In the mammalian Hippo pathway, mammalian Ste20-like kinases (MST1/2) and large tumor suppressor kinases (LATS1/2) regulate transcriptional co-activators, Yes-associated protein (YAP1) and Transcriptional co-activator with a PDZ-binding motif (TAZ). The Hippo pathway was initially thought to be quite straightforward; however, the identification of additional components has revealed its inherent complexity. Regulation of YAP1 and TAZ is not always dependent on MST1/2 and LATS1/2. MST1/2 and LATS1/2 play various YAP1/TAZ-independent roles, while YAP1 and TAZ cross-talk with other signaling pathways. In this review we focus on YAP1 and TAZ and discuss their regulation, function, and the consequences of their dysregulation.
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Affiliation(s)
- Manami Kodaka
- Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, 113-8519 Japan
| | - Yutaka Hata
- Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, 113-8519 Japan
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo, 113-8519 Japan
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272
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Piccolo S, Dupont S, Cordenonsi M. The biology of YAP/TAZ: hippo signaling and beyond. Physiol Rev 2014; 94:1287-312. [PMID: 25287865 DOI: 10.1152/physrev.00005.2014] [Citation(s) in RCA: 1188] [Impact Index Per Article: 118.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The transcriptional regulators YAP and TAZ are the focus of intense interest given their remarkable biological properties in development, tissue homeostasis and cancer. YAP and TAZ activity is key for the growth of whole organs, for amplification of tissue-specific progenitor cells during tissue renewal and regeneration, and for cell proliferation. In tumors, YAP/TAZ can reprogram cancer cells into cancer stem cells and incite tumor initiation, progression and metastasis. As such, YAP/TAZ are appealing therapeutic targets in cancer and regenerative medicine. Just like the function of YAP/TAZ offers a molecular entry point into the mysteries of tissue biology, their regulation by upstream cues is equally captivating. YAP/TAZ are well known for being the effectors of the Hippo signaling cascade, and mouse mutants in Hippo pathway components display remarkable phenotypes of organ overgrowth, enhanced stem cell content and reduced cellular differentiation. YAP/TAZ are primary sensors of the cell's physical nature, as defined by cell structure, shape and polarity. YAP/TAZ activation also reflects the cell "social" behavior, including cell adhesion and the mechanical signals that the cell receives from tissue architecture and surrounding extracellular matrix (ECM). At the same time, YAP/TAZ entertain relationships with morphogenetic signals, such as Wnt growth factors, and are also regulated by Rho, GPCRs and mevalonate metabolism. YAP/TAZ thus appear at the centerpiece of a signaling nexus by which cells take control of their behavior according to their own shape, spatial location and growth factor context.
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Affiliation(s)
- Stefano Piccolo
- Department of Molecular Medicine, University of Padua School of Medicine, Padua, Italy
| | - Sirio Dupont
- Department of Molecular Medicine, University of Padua School of Medicine, Padua, Italy
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273
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Gaspar P, Tapon N. Sensing the local environment: actin architecture and Hippo signalling. Curr Opin Cell Biol 2014; 31:74-83. [PMID: 25259681 DOI: 10.1016/j.ceb.2014.09.003] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/08/2014] [Accepted: 09/08/2014] [Indexed: 12/26/2022]
Abstract
The Hippo network is a major conserved growth suppressor pathway that participates in organ size control during development and prevents tumour formation during adult homeostasis. Recent evidence has implicated the actin cytoskeleton as a link between tissue architecture and Hippo signalling. In this review, we will consider the evidence and models proposed for the regulation of Hippo signalling by actin dynamics and structure. We cover aspects of signalling regulation by mechanotransduction, cytoskeletal tethering and the spatial reorganization of signalling components. We also examine the physiological and pathological contexts in which these mechanisms are relevant.
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Affiliation(s)
- Pedro Gaspar
- Apoptosis and Proliferation Control Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK; Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, Apartado 14, 2780-156 Oeiras, Portugal
| | - Nicolas Tapon
- Apoptosis and Proliferation Control Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK.
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274
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Abstract
Polarization of early embryos along cell contact patterns—referred to in this paper as radial polarization—provides a foundation for the initial cell fate decisions and morphogenetic movements of embryogenesis. Although polarity can be established through distinct upstream mechanisms in Caenorhabditis elegans, Xenopus laevis, and mouse embryos, in each species, it results in the restriction of PAR polarity proteins to contact-free surfaces of blastomeres. In turn, PAR proteins influence cell fates by affecting signaling pathways, such as Hippo and Wnt, and regulate morphogenetic movements by directing cytoskeletal asymmetries.
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Affiliation(s)
- Jeremy Nance
- Helen L. and Martin S. Kimmel Center for Biology and Medicine, the Skirball Institute of Biomolecular Medicine, and Department of Cell Biology, New York University School of Medicine, New York, NY 10016 Helen L. and Martin S. Kimmel Center for Biology and Medicine, the Skirball Institute of Biomolecular Medicine, and Department of Cell Biology, New York University School of Medicine, New York, NY 10016
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275
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Wicklow E, Blij S, Frum T, Hirate Y, Lang RA, Sasaki H, Ralston A. HIPPO pathway members restrict SOX2 to the inner cell mass where it promotes ICM fates in the mouse blastocyst. PLoS Genet 2014; 10:e1004618. [PMID: 25340657 PMCID: PMC4207610 DOI: 10.1371/journal.pgen.1004618] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 07/21/2014] [Indexed: 12/15/2022] Open
Abstract
Pluripotent epiblast (EPI) cells, present in the inner cell mass (ICM) of the mouse blastocyst, are progenitors of both embryonic stem (ES) cells and the fetus. Discovering how pluripotency genes regulate cell fate decisions in the blastocyst provides a valuable way to understand how pluripotency is normally established. EPI cells are specified by two consecutive cell fate decisions. The first decision segregates ICM from trophectoderm (TE), an extraembryonic cell type. The second decision subdivides ICM into EPI and primitive endoderm (PE), another extraembryonic cell type. Here, we investigate the roles and regulation of the pluripotency gene Sox2 during blastocyst formation. First, we investigate the regulation of Sox2 patterning and show that SOX2 is restricted to ICM progenitors prior to blastocyst formation by members of the HIPPO pathway, independent of CDX2, the TE transcription factor that restricts Oct4 and Nanog to the ICM. Second, we investigate the requirement for Sox2 in cell fate specification during blastocyst formation. We show that neither maternal (M) nor zygotic (Z) Sox2 is required for blastocyst formation, nor for initial expression of the pluripotency genes Oct4 or Nanog in the ICM. Rather, Z Sox2 initially promotes development of the primitive endoderm (PE) non cell-autonomously via FGF4, and then later maintains expression of pluripotency genes in the ICM. The significance of these observations is that 1) ICM and TE genes are spatially patterned in parallel prior to blastocyst formation and 2) both the roles and regulation of Sox2 in the blastocyst are unique compared to other pluripotency factors such as Oct4 or Nanog. Pluripotent stem cells can give rise to any cell type in the body, making them an attractive tool for regenerative medicine. Pluripotent stem cells can be derived from the mammalian embryo at the blastocyst stage or they can be created from mature adult cells by reprogramming. During reprogramming, SOX2 helps establish pluripotency, but it is not clear how SOX2 establishes pluripotency in the blastocyst. We evaluated where SOX2 is present, how SOX2 is regulated, and where SOX2 is active during blastocyst formation. Our data show that the roles and the regulation of SOX2 are unique compared to other pluripotency/reprogramming factors, such as OCT4 and NANOG. SOX2 marks pluripotent cells earlier than do other factors, but does not regulate pluripotency until several days later. Rather, the earlier role of SOX2 is to help establish the yolk sac lineage, which is essential for gestation.
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Affiliation(s)
- Eryn Wicklow
- Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Stephanie Blij
- Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Tristan Frum
- Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Yoshikazu Hirate
- Institute of Molecular Embryology and Genetics, Kumamoto University, Chuo-ku, Kumamoto, Japan
| | - Richard A. Lang
- Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Hiroshi Sasaki
- Institute of Molecular Embryology and Genetics, Kumamoto University, Chuo-ku, Kumamoto, Japan
| | - Amy Ralston
- Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail:
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276
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Gumbiner BM, Kim NG. The Hippo-YAP signaling pathway and contact inhibition of growth. J Cell Sci 2014; 127:709-17. [PMID: 24532814 DOI: 10.1242/jcs.140103] [Citation(s) in RCA: 252] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Hippo-YAP pathway mediates the control of cell proliferation by contact inhibition as well as other attributes of the physical state of cells in tissues. Several mechanisms sense the spatial and physical organization of cells, and function through distinct upstream modules to stimulate Hippo-YAP signaling: adherens junction or cadherin-catenin complexes, epithelial polarity and tight junction complexes, the FAT-Dachsous morphogen pathway, as well as cell shape, actomyosin or mechanotransduction. Soluble extracellular factors also regulate Hippo pathway signaling, often inhibiting its activity. Indeed, the Hippo pathway mediates a reciprocal relationship between contact inhibition and mitogenic signaling. As a result, cells at the edges of a colony, a wound in a tissue or a tumor are more sensitive to ambient levels of growth factors and more likely to proliferate, migrate or differentiate through a YAP and/or TAZ-dependent process. Thus, the Hippo-YAP pathway senses and responds to the physical organization of cells in tissues and coordinates these physical cues with classic growth-factor-mediated signaling pathways. This Commentary is focused on the biological significance of Hippo-YAP signaling and how upstream regulatory modules of the pathway interact to produce biological outcomes.
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Affiliation(s)
- Barry M Gumbiner
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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277
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Knott JG, Paul S. Transcriptional regulators of the trophoblast lineage in mammals with hemochorial placentation. Reproduction 2014; 148:R121-36. [PMID: 25190503 DOI: 10.1530/rep-14-0072] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mammalian reproduction is critically dependent on the trophoblast cell lineage, which assures proper establishment of maternal-fetal interactions during pregnancy. Specification of trophoblast cell lineage begins with the development of the trophectoderm (TE) in preimplantation embryos. Subsequently, other trophoblast cell types arise with the progression of pregnancy. Studies with transgenic animal models as well as trophoblast stem/progenitor cells have implicated distinct transcriptional and epigenetic regulators in trophoblast lineage development. This review focuses on our current understanding of transcriptional and epigenetic mechanisms regulating specification, determination, maintenance and differentiation of trophoblast cells.
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Affiliation(s)
- Jason G Knott
- Developmental Epigenetics LaboratoryDepartment of Animal Science, Michigan State University, East Lansing, Michigan 48824, USADepartment of Pathology and Laboratory MedicineInstitute of Reproductive Health and Regenerative Medicine, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
| | - Soumen Paul
- Developmental Epigenetics LaboratoryDepartment of Animal Science, Michigan State University, East Lansing, Michigan 48824, USADepartment of Pathology and Laboratory MedicineInstitute of Reproductive Health and Regenerative Medicine, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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278
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Sozen B, Can A, Demir N. Cell fate regulation during preimplantation development: a view of adhesion-linked molecular interactions. Dev Biol 2014; 395:73-83. [PMID: 25176042 DOI: 10.1016/j.ydbio.2014.08.028] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/20/2014] [Accepted: 08/21/2014] [Indexed: 12/01/2022]
Abstract
In the developmental process of the early mammalian embryo, it is crucial to understand how the identical cells in the early embryo later develop different fates. Along with existing models, many recently discovered molecular, cellular and developmental factors play roles in cell position, cell polarity and transcriptional networks in cell fate regulation during preimplantation. A structuring process known as compaction provides the "start signal" for cells to differentiate and orchestrates the developmental cascade. The proper intercellular junctional complexes assembled between blastomeres act as a conducting mechanism governing cellular diversification. Here, we provide an overview of the diversification process during preimplantation development as it relates to intercellular junctional complexes. We also evaluate transcriptional differences between embryonic lineages according to cell- cell adhesion and the contributions of adhesion to lineage commitment. These series of processes indicate that proper cell fate specification in the early mammalian embryo depends on junctional interactions and communication, which play essential roles during early morphogenesis.
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Affiliation(s)
- Berna Sozen
- Department of Histology and Embryology, School of Medicine, Akdeniz University, Campus, 07070 Antalya, Turkey
| | - Alp Can
- Department of Histology and Embryology, School of Medicine, Ankara University, Sihhiye, Ankara 06100, Turkey
| | - Necdet Demir
- Department of Histology and Embryology, School of Medicine, Akdeniz University, Campus, 07070 Antalya, Turkey.
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279
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Rayon T, Menchero S, Nieto A, Xenopoulos P, Crespo M, Cockburn K, Cañon S, Sasaki H, Hadjantonakis AK, de la Pompa JL, Rossant J, Manzanares M. Notch and hippo converge on Cdx2 to specify the trophectoderm lineage in the mouse blastocyst. Dev Cell 2014; 30:410-22. [PMID: 25127056 DOI: 10.1016/j.devcel.2014.06.019] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 05/12/2014] [Accepted: 06/23/2014] [Indexed: 11/15/2022]
Abstract
The first lineage choice in mammalian embryogenesis is that between the trophectoderm, which gives rise to the trophoblast of the placenta, and the inner cell mass, from which is derived the embryo proper and the yolk sac. The establishment of these lineages is preceded by the inside-versus-outside positioning of cells in the early embryo and stochastic expression of key transcription factors, which is then resolved into lineage-restricted expression. The regulatory inputs that drive this restriction and how they relate to cell position are largely unknown. Here, we show an unsuspected role of Notch signaling in regulating trophectoderm-specific expression of Cdx2 in cooperation with TEAD4. Notch activity is restricted to outer cells and is able to influence positional allocation of blastomeres, mediating preferential localization to the trophectoderm. Our results show that multiple signaling inputs at preimplantation stages specify the first embryonic lineages.
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Affiliation(s)
- Teresa Rayon
- Stem Cell Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Sergio Menchero
- Stem Cell Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Andres Nieto
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | | | - Miguel Crespo
- Stem Cell Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Katie Cockburn
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, 555 University Avenue, Toronto, ON M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Susana Cañon
- Stem Cell Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Hiroshi Sasaki
- Institute of Molecular Embryology and Genetics, Department of Cell Fate Control, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811, Japan
| | | | - Jose Luis de la Pompa
- Cardiovascular Developmental Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Janet Rossant
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, 555 University Avenue, Toronto, ON M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Miguel Manzanares
- Stem Cell Biology Program, Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain.
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280
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Watanabe T, Biggins JS, Tannan NB, Srinivas S. Limited predictive value of blastomere angle of division in trophectoderm and inner cell mass specification. Development 2014; 141:2279-88. [PMID: 24866117 PMCID: PMC4034423 DOI: 10.1242/dev.103267] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The formation of trophectoderm (TE) and pluripotent inner cell mass (ICM) is one of the earliest events during mammalian embryogenesis. It is believed that the orientation of division of polarised blastomeres in the 8- and 16-cell stage embryo determines the fate of daughter cells, based on how asymmetrically distributed lineage determinants are segregated. To investigate the relationship between angle of division and subsequent fate in unperturbed embryos, we constructed cellular resolution digital representations of the development of mouse embryos from the morula to early blastocyst stage, based on 4D confocal image volumes. We find that at the 16-cell stage, very few inside cells are initially produced as a result of cell division, but that the number increases due to cell movement. Contrary to expectations, outside cells at the 16-cell stage represent a heterogeneous population, with some fated to contributing exclusively to the TE and others capable of contributing to both the TE and ICM. Our data support the view that factors other than the angle of division, such as the position of a blastomere, play a major role in the specification of TE and ICM.
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Affiliation(s)
- Tomoko Watanabe
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - John S Biggins
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK
| | - Neeta Bala Tannan
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Shankar Srinivas
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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281
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Inhibition of RHO-ROCK signaling enhances ICM and suppresses TE characteristics through activation of Hippo signaling in the mouse blastocyst. Dev Biol 2014; 394:142-55. [PMID: 24997360 DOI: 10.1016/j.ydbio.2014.06.023] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 06/21/2014] [Accepted: 06/24/2014] [Indexed: 12/14/2022]
Abstract
Specification of the trophectoderm (TE) and inner cell mass (ICM) lineages in the mouse blastocyst correlates with cell position, as TE derives from outer cells whereas ICM from inner cells. Differences in position are reflected by cell polarization and Hippo signaling. Only in outer cells, the apical-basal cell polarity is established, and Hippo signaling is inhibited in such a manner that LATS1 and 2 (LATS1/2) kinases are prevented from phosphorylating YAP, a key transcriptional co-activator of the TE-specifying gene Cdx2. However, the molecular mechanisms that regulate these events are not fully understood. Here, we showed that inhibition of RHO-ROCK signaling enhances ICM and suppresses TE characteristics through activation of Hippo signaling and disruption of apical-basal polarity. Embryos treated with ROCK inhibitor Y-27632 exhibited elevated expression of ICM marker NANOG and reduced expression of CDX2 at the blastocyst stage. Y-27632-treated embryos failed to accumulate YAP in the nucleus, although it was rescued by concomitant inhibition of LATS1/2. Segregation between apical and basal polarity regulators, namely PARD6B, PRKCZ, SCRIB, and LLGL1, was dampened by Y-27632 treatment, whereas some of the polarization events at the late 8-cell stage such as compaction and apical localization of p-ERM and tyrosinated tubulin occurred normally. Similar abnormalities of Hippo signaling and apical-basal polarization were also observed in embryos that were treated with RHO GTPases inhibitor. These results suggest that RHO-ROCK signaling plays an essential role in regulating Hippo signaling and cell polarization to enable proper specification of the ICM and TE lineages.
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282
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Anani S, Bhat S, Honma-Yamanaka N, Krawchuk D, Yamanaka Y. Initiation of Hippo signaling is linked to polarity rather than to cell position in the pre-implantation mouse embryo. Development 2014; 141:2813-24. [PMID: 24948601 DOI: 10.1242/dev.107276] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the mouse embryo, asymmetric divisions during the 8-16 cell division generate two cell types, polar and apolar cells, that are allocated to outer and inner positions, respectively. This outer/inner configuration is the first sign of the formation of the first two cell lineages: trophectoderm (TE) and inner cell mass (ICM). Outer polar cells become TE and give rise to the placenta, whereas inner apolar cells become ICM and give rise to the embryo proper and yolk sac. Here, we analyze the frequency of asymmetric divisions during the 8-16 cell division and assess the relationships between cell polarity, cell and nuclear position, and Hippo signaling activation, the pathway that initiates lineage-specific gene expression in 16-cell embryos. Although the frequency of asymmetric divisions varied in each embryo, we found that more than six blastomeres divided asymmetrically in most embryos. Interestingly, many apolar cells in 16-cell embryos were located at outer positions, whereas only one or two apolar cells were located at inner positions. Live imaging analysis showed that outer apolar cells were eventually internalized by surrounding polar cells. Using isolated 8-cell blastomeres, we carefully analyzed the internalization process of apolar cells and found indications of higher cortical tension in apolar cells than in polar cells. Last, we found that apolar cells activate Hippo signaling prior to taking inner positions. Our results suggest that polar and apolar cells have intrinsic differences that establish outer/inner configuration and differentially regulate Hippo signaling to activate lineage-specific gene expression programs.
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Affiliation(s)
- Shihadeh Anani
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada Department of Human Genetics, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada
| | - Shivani Bhat
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada
| | - Nobuko Honma-Yamanaka
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada
| | - Dayana Krawchuk
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada
| | - Yojiro Yamanaka
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada Department of Human Genetics, McGill University, 1160 Pine Avenue West, Montreal, QC H3A1A3, Canada
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283
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Kojima Y, Tam OH, Tam PPL. Timing of developmental events in the early mouse embryo. Semin Cell Dev Biol 2014; 34:65-75. [PMID: 24954643 DOI: 10.1016/j.semcdb.2014.06.010] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 06/04/2014] [Accepted: 06/11/2014] [Indexed: 01/29/2023]
Abstract
The timing of developmental events during early mouse development has been investigated in embryos that have been subject to experimental manipulation of cell number and tissue mass. These phenomenological studies revealed that the timing of preimplantation events, such as compaction, formation of blastocyst cavity and lineage allocation is correlated with the rounds of cleavage division or DNA replication of the blastomeres. Timing of postimplantation processes, such as formation of proamniotic cavity and onset of gastrulation is sensitive to cell number and probably the tissue mass, which may be measured by a mechanosensory signaling mechanism. Developmental changes in these two physical attributes are correlated with the cell proliferative activity and the growth trajectory of the whole embryo prior to the transit to organogenesis. During organogenesis, timing of morphogenesis appears to be regulated by individual devices that could be uncoupled during compensatory growth. Insights of the timing mechanism may be gleaned from the analysis of genomic activity associated with the transition through developmental milestones.
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Affiliation(s)
- Yoji Kojima
- Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501, Japan.
| | - Oliver H Tam
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
| | - Patrick P L Tam
- Embryology Unit, Children's Medical Research Institute and Sydney Medical School, University of Sydney, Westmead, NSW 2145, Australia.
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284
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Varelas X. The Hippo pathway effectors TAZ and YAP in development, homeostasis and disease. Development 2014; 141:1614-26. [PMID: 24715453 DOI: 10.1242/dev.102376] [Citation(s) in RCA: 470] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Studies over the past 20 years have defined the Hippo signaling pathway as a major regulator of tissue growth and organ size. Diverse roles for the Hippo pathway have emerged, the majority of which in vertebrates are determined by the transcriptional regulators TAZ and YAP (TAZ/YAP). Key processes regulated by TAZ/YAP include the control of cell proliferation, apoptosis, movement and fate. Accurate control of the levels and localization of these factors is thus essential for early developmental events, as well as for tissue homeostasis, repair and regeneration. Recent studies have revealed that TAZ/YAP activity is regulated by mechanical and cytoskeletal cues as well as by various extracellular factors. Here, I provide an overview of these and other regulatory mechanisms and outline important developmental processes controlled by TAZ and YAP.
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Affiliation(s)
- Xaralabos Varelas
- Department of Biochemistry, Boston University School of Medicine, 72 East Concord Street, Room K-620, Boston, MA 02118, USA
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285
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Kuijk E, Geijsen N, Cuppen E. Pluripotency in the light of the developmental hourglass. Biol Rev Camb Philos Soc 2014; 90:428-43. [DOI: 10.1111/brv.12117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 04/10/2014] [Accepted: 04/28/2014] [Indexed: 01/09/2023]
Affiliation(s)
- Ewart Kuijk
- Hubrecht Institute, KNAW and University Medical Center Utrecht; Utrecht 3584 CT The Netherlands
| | - Niels Geijsen
- Hubrecht Institute, KNAW and University Medical Center Utrecht; Utrecht 3584 CT The Netherlands
- Department of Companion Animals; School of Veterinary Medicine, Utrecht University; Utrecht 3584 CM The Netherlands
| | - Edwin Cuppen
- Hubrecht Institute, KNAW and University Medical Center Utrecht; Utrecht 3584 CT The Netherlands
- Center for Molecular Medicine; UMC Utrecht; Universiteitsweg 100 Utrecht 3584 GG The Netherlands
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286
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Abstract
The Hippo signaling pathway, consisting of a highly conserved kinase cascade (MST and Lats) and downstream transcription coactivators (YAP and TAZ), plays a key role in tissue homeostasis and organ size control by regulating tissue-specific stem cells. Moreover, this pathway plays a prominent role in tissue repair and regeneration. Dysregulation of the Hippo pathway is associated with cancer development. Recent studies have revealed a complex network of upstream inputs, including cell density, mechanical sensation, and G-protein-coupled receptor (GPCR) signaling, that modulate Hippo pathway activity. This review focuses on the role of the Hippo pathway in stem cell biology and its potential implications in tissue homeostasis and cancer.
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Affiliation(s)
- Jung-Soon Mo
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego La Jolla, CA, USA
| | - Hyun Woo Park
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego La Jolla, CA, USA
| | - Kun-Liang Guan
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego La Jolla, CA, USA
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287
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Wen D, Saiz N, Rosenwaks Z, Hadjantonakis AK, Rafii S. Completely ES cell-derived mice produced by tetraploid complementation using inner cell mass (ICM) deficient blastocysts. PLoS One 2014; 9:e94730. [PMID: 24733255 PMCID: PMC3986396 DOI: 10.1371/journal.pone.0094730] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 03/18/2014] [Indexed: 01/15/2023] Open
Abstract
Tetraploid complementation is often used to produce mice from embryonic stem cells (ESCs) by injection of diploid (2n) ESCs into tetraploid (4n) blastocysts (ESC-derived mice). This method has also been adapted to mouse cloning and the derivation of mice from induced pluripotent stem (iPS) cells. However, the underlying mechanism(s) of the tetraploid complementation remains largely unclear. Whether this approach can give rise to completely ES cell-derived mice is an open question, and has not yet been unambiguously proven. Here, we show that mouse tetraploid blastocysts can be classified into two groups, according to the presence or absence of an inner cell mass (ICM). We designate these as type a (presence of ICM at blastocyst stage) or type b (absence of ICM). ESC lines were readily derived from type a blastocysts, suggesting that these embryos retain a pluripotent epiblast compartment; whereas the type b blastocysts possessed very low potential to give rise to ESC lines, suggesting that they had lost the pluripotent epiblast. When the type a blastocysts were used for tetraploid complementation, some of the resulting mice were found to be 2n/4n chimeric; whereas when type b blastocysts were used as hosts, the resulting mice are all completely ES cell-derived, with the newborn pups displaying a high frequency of abdominal hernias. Our results demonstrate that completely ES cell-derived mice can be produced using ICM-deficient 4n blastocysts, and provide evidence that the exclusion of tetraploid cells from the fetus in 2n/4n chimeras can largely be attributed to the formation of ICM-deficient blastocysts.
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Affiliation(s)
- Duancheng Wen
- Ansary Stem Cell Institute and Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
- Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (DW); (SR)
| | - Nestor Saiz
- Developmental Biology Program, Sloan Kettering Institute, New York, New York, United States of America
| | - Zev Rosenwaks
- Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | | | - Shahin Rafii
- Ansary Stem Cell Institute and Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (DW); (SR)
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288
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Mana-Capelli S, Paramasivam M, Dutta S, McCollum D. Angiomotins link F-actin architecture to Hippo pathway signaling. Mol Biol Cell 2014; 25:1676-85. [PMID: 24648494 PMCID: PMC4019498 DOI: 10.1091/mbc.e13-11-0701] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Angiomotin proteins, together with LATS kinase, regulate the Hippo pathway transcriptional coactivator YAP in response to changes in the F-actin cytoskeleton. Competition between F-actin and YAP for binding to angiomotins makes YAP regulation responsive to F-actin levels. Phosphorylation by LATS can switch angiomotins from F-actin to YAP binding. The Hippo pathway regulates the transcriptional coactivator YAP to control cell proliferation, organ size, and stem cell maintenance. Multiple factors, such as substrate stiffness, cell density, and G protein–coupled receptor signaling, regulate YAP through their effects on the F-actin cytoskeleton, although the mechanism is not known. Here we show that angiomotin proteins (AMOT130, AMOTL1, and AMOTL2) connect F-actin architecture to YAP regulation. First, we show that angiomotins are required to relocalize YAP to the cytoplasm in response to various manipulations that perturb the actin cytoskeleton. Second, angiomotins associate with F-actin through a conserved F-actin–binding domain, and mutants defective for F-actin binding show enhanced ability to retain YAP in the cytoplasm. Third, F-actin and YAP compete for binding to AMOT130, explaining how F-actin inhibits AMOT130-mediated cytoplasmic retention of YAP. Furthermore, we find that LATS can synergize with F-actin perturbations by phosphorylating free AMOT130 to keep it from associating with F-actin. Together these results uncover a mechanism for how F-actin levels modulate YAP localization, allowing cells to make developmental and proliferative decisions based on diverse inputs that regulate actin architecture.
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Affiliation(s)
- Sebastian Mana-Capelli
- Department of Biochemistry and Molecular Pharmacology and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, MA 01605
| | - Murugan Paramasivam
- Department of Biochemistry and Molecular Pharmacology and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, MA 01605
| | - Shubham Dutta
- Department of Biochemistry and Molecular Pharmacology and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, MA 01605
| | - Dannel McCollum
- Department of Biochemistry and Molecular Pharmacology and Program in Cell Dynamics, University of Massachusetts Medical School, Worcester, MA 01605
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289
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Gavilan HS, Kulikauskas RM, Gutmann DH, Fehon RG. In vivo functional analysis of the human NF2 tumor suppressor gene in Drosophila. PLoS One 2014; 9:e90853. [PMID: 24595234 PMCID: PMC3942481 DOI: 10.1371/journal.pone.0090853] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 02/04/2014] [Indexed: 11/19/2022] Open
Abstract
The proper control of tissue growth is essential during normal development and an important problem in human disease. Merlin, the product of the Neurofibromatosis 2 tumor suppressor gene, has been extensively studied to understand its functions in growth control. Here we describe experiments in which we used Drosophila as an in vivo system to test the functions of the normal human NF2 gene products and patient-derived mutant alleles. Although the predominant NF2 gene isoform, isoform 1, could functionally replace the Drosophila Merlin gene, a second isoform with a distinct C-terminal tail could not. Immunofluorescence studies show that the two isoforms have distinct subcellular localizations when expressed in the polarized imaginal epithelium, and function in genetic rescue assays correlates with apical localization of the NF2 protein. Interestingly, we found that a patient-derived missense allele, NF2L64P, appears to be temperature sensitive. These studies highlight the utility of Drosophila for in vivo functional analysis of highly conserved human disease genes.
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Affiliation(s)
- Heather S. Gavilan
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - Rima M. Kulikauskas
- Department of Biology, Duke University, Durham, North Carolina, United States of America
| | - David H. Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Richard G. Fehon
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois, United States of America
- * E-mail:
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290
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Hirate Y, Sasaki H. The role of angiomotin phosphorylation in the Hippo pathway during preimplantation mouse development. Tissue Barriers 2014; 2:e28127. [PMID: 24843842 PMCID: PMC4022607 DOI: 10.4161/tisb.28127] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 02/01/2014] [Accepted: 02/05/2014] [Indexed: 11/19/2022] Open
Abstract
The Hippo signaling pathway regulates a number of cellular events, including the control of cell fates in preimplantation mouse embryos. The inner and outer cells of the embryo show high and low levels of Hippo signaling, respectively. This position-dependent Hippo signaling promotes the specification of distinct cell fates. In a recent paper, we identified the molecular mechanism that controls Hippo signaling in preimplantation embryos. The junction-associated scaffold protein Angiomotin (Amot) plays a key role in this mechanism. At the adherens junctions of the inner cells, Amot activates the Hippo pathway by recruiting and activating the protein kinase large tumor suppressor (Lats). In contrast, Amot at the apical membrane of the outer cells suppresses Hippo signaling by interacting with F-actin. The phosphorylation of Amot inhibits its interaction with F-actin and activates Hippo signaling. We propose that Amot acts as a molecular switch for the Hippo pathway and links F-actin with Lats activity.
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Affiliation(s)
- Yoshikazu Hirate
- Department of Cell Fate Control; Institute of Molecular Embryology and Genetics; Kumamoto University; Kumamoto, Japan
| | - Hiroshi Sasaki
- Department of Cell Fate Control; Institute of Molecular Embryology and Genetics; Kumamoto University; Kumamoto, Japan
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291
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The Angiomotins--from discovery to function. FEBS Lett 2014; 588:2693-703. [PMID: 24548561 DOI: 10.1016/j.febslet.2014.02.006] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 02/05/2014] [Accepted: 02/06/2014] [Indexed: 12/13/2022]
Abstract
Angiomotins were originally identified as angiostatin binding proteins and implicated in the regulation of endothelial cell migration. Recent studies have shed light on the role of Angiomotins and other members of the Motin protein family in epithelial cells and in pathways directly linked to the pathogenesis of cancer. In particular, Motins have been shown to play a role in signaling pathways regulated by small G-proteins and the Hippo-YAP pathway. In this review the role of the Motin protein family in these signaling pathways will be described and open questions will be discussed.
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292
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Latos P, Hemberger M. Review: The transcriptional and signalling networks of mouse trophoblast stem cells. Placenta 2014; 35 Suppl:S81-5. [DOI: 10.1016/j.placenta.2013.10.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 10/22/2013] [Accepted: 10/23/2013] [Indexed: 02/02/2023]
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293
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294
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Johnson R, Halder G. The two faces of Hippo: targeting the Hippo pathway for regenerative medicine and cancer treatment. Nat Rev Drug Discov 2013; 13:63-79. [PMID: 24336504 DOI: 10.1038/nrd4161] [Citation(s) in RCA: 701] [Impact Index Per Article: 63.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The Hippo signalling pathway is an emerging growth control and tumour suppressor pathway that regulates cell proliferation and stem cell functions. Defects in Hippo signalling and hyperactivation of its downstream effectors Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) contribute to the development of cancer, which suggests that pharmacological inhibition of YAP and TAZ activity may be an effective anticancer strategy. Conversely, YAP and TAZ can also have beneficial roles in stimulating tissue repair and regeneration following injury, so their activation may be therapeutically useful in these contexts. A complex network of intracellular and extracellular signalling pathways that modulate YAP and TAZ activities have recently been identified. Here, we review the regulation of the Hippo signalling pathway, its functions in normal homeostasis and disease, and recent progress in the identification of small-molecule pathway modulators.
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Affiliation(s)
- Randy Johnson
- 1] Department of Biochemistry and Molecular Biology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA. [2] Genes and Development Program, and Cancer Biology Program, Graduate School for Biological Sciences, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA. [3] Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Georg Halder
- VIB Center for the Biology of Disease, KU Leuven Center for Human Genetics, University of Leuven 3000, Belgium
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295
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Lanner F. Lineage specification in the early mouse embryo. Exp Cell Res 2013; 321:32-9. [PMID: 24333597 DOI: 10.1016/j.yexcr.2013.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 11/30/2013] [Accepted: 12/03/2013] [Indexed: 11/30/2022]
Abstract
Before the mammalian embryo is ready to implant in the uterine wall, the single cell zygote must divide and differentiate into three distinct tissues; trophectoderm (prospective placenta), primitive endoderm (prospective yolk sac), and pluripotent epiblast cells which will form the embryo proper. In this review I will discuss our current understanding of how positional information, cell polarization, signaling pathways, and transcription factor networks converge to drive and regulate the progressive segregation of the first three cell types in the mouse embryo.
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Affiliation(s)
- Fredrik Lanner
- Karolinska Institutet, Department of Clinical Science, Intervention and Technology, Karolinska Universitetssjukhuset, K 57 CLINTEC, 141 86 Stockholm, Sweden.
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296
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Sheng G. Day-1 chick development. Dev Dyn 2013; 243:357-67. [DOI: 10.1002/dvdy.24087] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 10/22/2013] [Accepted: 10/22/2013] [Indexed: 02/04/2023] Open
Affiliation(s)
- Guojun Sheng
- Laboratory for Early Embryogenesis; RIKEN Center for Developmental Biology; Kobe Hyogo Japan
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297
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Chen SN, Gurha P, Lombardi R, Ruggiero A, Willerson JT, Marian AJ. The hippo pathway is activated and is a causal mechanism for adipogenesis in arrhythmogenic cardiomyopathy. Circ Res 2013; 114:454-68. [PMID: 24276085 DOI: 10.1161/circresaha.114.302810] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
RATIONALE Mutations in the intercalated disc proteins, such as plakophilin 2 (PKP2), cause arrhythmogenic cardiomyopathy (AC). AC is characterized by the replacement of cardiac myocytes by fibro-adipocytes, cardiac dysfunction, arrhythmias, and sudden death. OBJECTIVE To delineate the molecular pathogenesis of AC. METHODS AND RESULTS Localization and levels of selected intercalated disc proteins, including signaling molecules, were markedly reduced in human hearts with AC. Altered protein constituents of intercalated discs were associated with activation of the upstream Hippo molecules in the human hearts, in Nkx2.5-Cre:Dsp(W/F) and Myh6:Jup mouse models of AC, and in the PKP2 knockdown HL-1 myocytes (HL-1(PKP2:shRNA)). Level of active protein kinase C-α isoform, which requires PKP2 for activity, was reduced. In contrast, neurofibromin 2 (or Merlin), a molecule upstream of the Hippo pathway and that is inactivated by protein kinase C-α isoform, was activated. Consequently, the downstream Hippo molecules mammalian STE20-like protein kinases 1/2 (MST1/2), large tumor suppressor kinases 1/2 (LATS1/2), and Yes-associated protein (YAP) (the latter is the effector of the pathway) were phosphorylated. Coimmunoprecipitation detected binding of phosphorylated YAP, phosphorylated β-catenin, and junction protein plakoglobin (the latter translocated from the junction). RNA sequencing, transcript quantitative polymerase chain reaction, and reporter assays showed suppressed activity of SV40 transcriptional enhancer factor domain (TEAD) and transcription factor 7-like 2 (TCF7L2), which are transcription factors of the Hippo and the canonical Wnt signaling, respectively. In contrast, adipogenesis was enhanced. Simultaneous knockdown of Lats1/2, molecules upstream to YAP, rescued inactivation of YAP and β-catenin and adipogenesis in the HL-1(PKP2:shRNA) myocytes. CONCLUSIONS Molecular remodeling of the intercalated discs leads to pathogenic activation of the Hippo pathway, suppression of the canonical Wnt signaling, and enhanced adipogenesis in AC. The findings offer novel mechanisms for the pathogenesis of AC.
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Affiliation(s)
- Suet Nee Chen
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine and Department of Medicine, The University of Texas Health Sciences Center at Houston, Houston, TX; and Texas Heart Institute, Houston, TX
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298
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Laeno AMA, Tamashiro DAA, Alarcon VB. Rho-associated kinase activity is required for proper morphogenesis of the inner cell mass in the mouse blastocyst. Biol Reprod 2013; 89:122. [PMID: 23946538 DOI: 10.1095/biolreprod.113.109470] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The blastocyst consists of the outer layer of trophectoderm and pluripotent inner cell mass (ICM), the precursor of the placenta and fetus, respectively. During blastocyst expansion, the ICM adopts a compact, ovoidal shape, whose proper morphology is crucial for normal embryogenesis. Rho-associated kinase (ROCK), an effector of small GTPase RHO signaling, mediates the diverse cellular processes of morphogenesis, but its role in ICM morphogenesis is unclear. Here, we demonstrate that ROCK is required for cohesion of ICM cells and formation of segregated tissues called primitive endoderm (PrE) and epiblast (Epi) in the ICM of the mouse blastocyst. Blastocyst treatment with ROCK inhibitors Y-27632 and Fasudil caused widening or spreading of the ICM, and intermingling of PrE and Epi. Widening of ICM was independent of trophectoderm because isolated ICMs as well as colonies of mouse embryonic stem cells (mESC) also spread upon Y-27632 treatment. PrE, Epi, and trophectoderm cell numbers were similar between control and treated blastocysts, suggesting that ROCK inhibition affected ICM morphology but not lineage differentiation. Rock1 and Rock2 knockdown via RNA interference in mESC also induced spreading, supporting the conclusion that morphological defects caused by the pharmacological inhibitors were due to ROCK inactivation. When blastocysts were transferred into surrogates, implantation efficiencies were unaffected by ROCK inhibition, but treated blastocysts yielded greater fetal loss. These results show that proper ICM morphology is dependent on ROCK activity and is crucial for fetal development. Our studies have wider implication for improving efficiencies of human assisted reproductive technologies that diminish pregnancy loss and promote successful births.
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Affiliation(s)
- Arlene May A Laeno
- Institute for Biogenesis Research, Department of Anatomy, Biochemistry and Physiology, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii
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299
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Chan SW, Lim CJ, Guo F, Tan I, Leung T, Hong W. Actin-binding and cell proliferation activities of angiomotin family members are regulated by Hippo pathway-mediated phosphorylation. J Biol Chem 2013; 288:37296-307. [PMID: 24225952 DOI: 10.1074/jbc.m113.527598] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Whether the Hippo pathway has downstream targets other than YAP and TAZ is unknown. In this report, we have identified angiomotin (Amot) family members as novel substrates of Hippo core kinases. The N-terminal regions of Amot proteins contain a conserved HXRXXS consensus site for LATS1/2-mediated phosphorylation. Phospho-specific antibodies showed that Hippo core kinases could mediate phosphorylation of endogenous as well as exogenous Amot family members. Knockdown of LATS1 and LATS2 endogenously reduced the phosphorylation of Amots detected by the phospho-specific antibodies. Mutation of the serine to alanine within this HXRXXS site in Amot and AmotL2 established that this site was essential for Hippo core kinase-mediated phosphorylation. Wild-type and non-phosphorylated Amot (Amot-S175A) were targeted to actin filaments, whereas phospho-mimic Amot (Amot-S175D) failed to be localized with actin. Overexpression of LATS2 caused dissociation of Amot from actin but not Amot-S175A. Mapping of the actin-binding site of Amot showed that serine 175 of Amot was important for the actin-binding activity. Amot-S175A promoted, whereas Amot and Amot-S175D inhibited, cell proliferation. These results collectively suggest that the Hippo pathway negatively regulates the actin-binding activity of Amot family members through direct phosphorylation.
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Affiliation(s)
- Siew Wee Chan
- From the Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673 and
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300
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Dai X, She P, Chi F, Feng Y, Liu H, Jin D, Zhao Y, Guo X, Jiang D, Guan KL, Zhong TP, Zhao B. Phosphorylation of angiomotin by Lats1/2 kinases inhibits F-actin binding, cell migration, and angiogenesis. J Biol Chem 2013; 288:34041-34051. [PMID: 24106267 DOI: 10.1074/jbc.m113.518019] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Hippo tumor suppressor pathway plays important roles in organ size control through Lats1/2 mediated phosphorylation of the YAP/TAZ transcription co-activators. However, YAP/TAZ independent functions of the Hippo pathway are largely unknown. Here we report a novel role of the Hippo pathway in angiogenesis. Angiomotin p130 isoform (AMOTp130) is phosphorylated on a conserved HXRXXS motif by Lats1/2 downstream of GPCR signaling. Phosphorylation disrupts AMOT interaction with F-actin and correlates with reduced F-actin stress fibers and focal adhesions. Furthermore, phosphorylation of AMOT by Lats1/2 inhibits endothelial cell migration in vitro and angiogenesis in zebrafish embryos in vivo. Thus AMOT is a direct substrate of Lats1/2 mediating functions of the Hippo pathway in endothelial cell migration and angiogenesis.
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Affiliation(s)
- Xiaoming Dai
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Peilu She
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Fangtao Chi
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ying Feng
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Huan Liu
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Daqing Jin
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Yiqiang Zhao
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaocan Guo
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Dandan Jiang
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Kun-Liang Guan
- Department of Pharmacology and Moores Cancer Center, University of California at San Diego, La Jolla, California 92093-0815
| | - Tao P Zhong
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Bin Zhao
- Life Sciences Institute and Innovation Center for Cell Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China.
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