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Kumar A, BharathwajChetty B, Manickasamy MK, Unnikrishnan J, Alqahtani MS, Abbas M, Almubarak HA, Sethi G, Kunnumakkara AB. Natural compounds targeting YAP/TAZ axis in cancer: Current state of art and challenges. Pharmacol Res 2024; 203:107167. [PMID: 38599470 DOI: 10.1016/j.phrs.2024.107167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 04/12/2024]
Abstract
Cancer has become a burgeoning global healthcare concern marked by its exponential growth and significant economic ramifications. Though advancements in the treatment modalities have increased the overall survival and quality of life, there are no definite treatments for the advanced stages of this malady. Hence, understanding the diseases etiologies and the underlying molecular complexities, will usher in the development of innovative therapeutics. Recently, YAP/TAZ transcriptional regulation has been of immense interest due to their role in development, tissue homeostasis and oncogenic transformations. YAP/TAZ axis functions as coactivators within the Hippo signaling cascade, exerting pivotal influence on processes such as proliferation, regeneration, development, and tissue renewal. In cancer, YAP is overexpressed in multiple tumor types and is associated with cancer stem cell attributes, chemoresistance, and metastasis. Activation of YAP/TAZ mirrors the cellular "social" behavior, encompassing factors such as cell adhesion and the mechanical signals transmitted to the cell from tissue structure and the surrounding extracellular matrix. Therefore, it presents a significant vulnerability in the clogs of tumors that could provide a wide window of therapeutic effectiveness. Natural compounds have been utilized extensively as successful interventions in the management of diverse chronic illnesses, including cancer. Owing to their capacity to influence multiple genes and pathways, natural compounds exhibit significant potential either as adjuvant therapy or in combination with conventional treatment options. In this review, we delineate the signaling nexus of YAP/TAZ axis, and present natural compounds as an alternate strategy to target cancer.
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Affiliation(s)
- Aviral Kumar
- Cancer Biology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IITG), Guwahati, Assam 781039, India
| | - Bandari BharathwajChetty
- Cancer Biology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IITG), Guwahati, Assam 781039, India
| | - Mukesh Kumar Manickasamy
- Cancer Biology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IITG), Guwahati, Assam 781039, India
| | - Jyothsna Unnikrishnan
- Cancer Biology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IITG), Guwahati, Assam 781039, India
| | - Mohammed S Alqahtani
- Radiological Sciences Department, College of Applied Medical Sciences, King Khalid University, Abha 61421, Saudi Arabia; BioImaging Unit, Space Research Centre, Michael Atiyah Building, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Mohamed Abbas
- Electrical Engineering Department, College of Engineering, King Khalid University, Abha 61421, Saudi Arabia
| | - Hassan Ali Almubarak
- Division of Radiology, Department of Medicine, College of Medicine and Surgery, King Khalid University, Abha 61421, Saudi Arabia
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 16 Medical Drive, Singapore 117600, Singapore; NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, 117699, Singapore.
| | - Ajaikumar B Kunnumakkara
- Cancer Biology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati (IITG), Guwahati, Assam 781039, India.
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Liu A, O’Connell J, Wall F, Carthew RW. Scaling between cell cycle duration and wing growth is regulated by Fat-Dachsous signaling in Drosophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.01.551465. [PMID: 38645118 PMCID: PMC11030236 DOI: 10.1101/2023.08.01.551465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
The atypical cadherins Fat and Dachsous (Ds) signal through the Hippo pathway to regulate growth of numerous organs, including the Drosophila wing. Here, we find that Ds-Fat signaling tunes a unique feature of cell proliferation found to control the rate of wing growth during the third instar larval phase. The duration of the cell cycle increases in direct proportion to the size of the wing, leading to linear-like growth during the third instar. Ds-Fat signaling enhances the rate at which the cell cycle lengthens with wing size, thus diminishing the rate of wing growth. We show that this results in a complex but stereotyped relative scaling of wing growth with body growth in Drosophila. Finally, we examine the dynamics of Fat and Ds protein distribution in the wing, observing graded distributions that change during growth. However, the significance of these dynamics is unclear since perturbations in expression have negligible impact on wing growth.
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Affiliation(s)
- Andrew Liu
- Department of Molecular Biosciences, Northwestern University, Evanston IL
- NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston IL
| | - Jessica O’Connell
- Department of Molecular Biosciences, Northwestern University, Evanston IL
| | - Farley Wall
- Department of Molecular Biosciences, Northwestern University, Evanston IL
| | - Richard W. Carthew
- Department of Molecular Biosciences, Northwestern University, Evanston IL
- NSF-Simons Center for Quantitative Biology, Northwestern University, Evanston IL
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Chess MM, Douglas W, Saunders J, Ettensohn CA. Genome-wide identification and spatiotemporal expression analysis of cadherin superfamily members in echinoderms. EvoDevo 2023; 14:15. [PMID: 38124068 PMCID: PMC10734073 DOI: 10.1186/s13227-023-00219-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Cadherins are calcium-dependent transmembrane cell-cell adhesion proteins that are essential for metazoan development. They consist of three subfamilies: classical cadherins, which bind catenin, protocadherins, which contain 6-7 calcium-binding repeat domains, and atypical cadherins. Their functions include forming adherens junctions, establishing planar cell polarity (PCP), and regulating cell shape, proliferation, and migration. Because they are basal deuterostomes, echinoderms provide important insights into bilaterian evolution, but their only well-characterized cadherin is G-cadherin, a classical cadherin that is expressed by many embryonic epithelia. We aimed to better characterize echinoderm cadherins by conducting phylogenetic analyses and examining the spatiotemporal expression patterns of cadherin-encoding genes during Strongylocentrotus purpuratus development. RESULTS Our phylogenetic analyses conducted on two echinoid, three asteroid, and one crinoid species identified ten echinoderm cadherins, including one deuterostome-specific ortholog, cadherin-23, and an echinoderm-specific atypical cadherin that possibly arose in an echinoid-asteroid ancestor. Catenin-binding domains in dachsous-2 orthologs were found to be a deuterostome-specific innovation that was selectively lost in mouse, while those in Fat4 orthologs appeared to be Ambulacraria-specific and were selectively lost in non-crinoid echinoderms. The identified suite of echinoderm cadherins lacks vertebrate-specific innovations but contains two proteins that are present in protostomes and absent from mouse. The spatiotemporal expression patterns of four embryonically expressed cadherins (fat atypical cadherins 1 and 4, dachsous-2, and protocadherin-9) were dynamic and mirrored the expression pattern of Frizzled 5/8, a non-canonical Wnt PCP pathway receptor protein essential for archenteron morphogenesis. CONCLUSIONS The echinoderm cadherin toolkit is more similar to that of an ancient bilaterian predating protostomes and deuterostomes than it is to the suite of cadherins found in extant vertebrates. However, it also appears that deuterostomes underwent several cadherin-related innovations. Based on their similar spatiotemporal expression patterns and orthologous relationships to PCP-related and tumor-suppressing proteins, we hypothesize that sea urchin cadherins may play a role in regulating the shape and growth of embryonic epithelia and organs. Future experiments will examine cadherin expression in non-echinoid echinoderms and explore the functions of cadherins during echinoderm development.
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Affiliation(s)
- Macie M Chess
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - William Douglas
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Josiah Saunders
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Charles A Ettensohn
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
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Fulford AD, Enderle L, Rusch J, Hodzic D, Holder MV, Earl A, Oh RH, Tapon N, McNeill H. Expanded directly binds conserved regions of Fat to restrain growth via the Hippo pathway. J Cell Biol 2023; 222:e202204059. [PMID: 37071483 PMCID: PMC10120405 DOI: 10.1083/jcb.202204059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 11/26/2022] [Accepted: 02/09/2023] [Indexed: 04/19/2023] Open
Abstract
The Hippo pathway is a conserved and critical regulator of tissue growth. The FERM protein Expanded is a key signaling hub that promotes activation of the Hippo pathway, thereby inhibiting the transcriptional co-activator Yorkie. Previous work identified the polarity determinant Crumbs as a primary regulator of Expanded. Here, we show that the giant cadherin Fat also regulates Expanded directly and independently of Crumbs. We show that direct binding between Expanded and a highly conserved region of the Fat cytoplasmic domain recruits Expanded to the apicolateral junctional zone and stabilizes Expanded. In vivo deletion of Expanded binding regions in Fat causes loss of apical Expanded and promotes tissue overgrowth. Unexpectedly, we find Fat can bind its ligand Dachsous via interactions of their cytoplasmic domains, in addition to the known extracellular interactions. Importantly, Expanded is stabilized by Fat independently of Dachsous binding. These data provide new mechanistic insights into how Fat regulates Expanded, and how Hippo signaling is regulated during organ growth.
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Affiliation(s)
- Alexander D. Fulford
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Leonie Enderle
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Jannette Rusch
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Didier Hodzic
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Maxine V. Holder
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, London, UK
| | - Alex Earl
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Robin Hyunseo Oh
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Nicolas Tapon
- Apoptosis and Proliferation Control Laboratory, The Francis Crick Institute, London, UK
| | - Helen McNeill
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
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Kasiah J, McNeill H. Fat and Dachsous cadherins in mammalian development. Curr Top Dev Biol 2023; 154:223-244. [PMID: 37100519 DOI: 10.1016/bs.ctdb.2023.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Cell growth and patterning are critical for tissue development. Here we discuss the evolutionarily conserved cadherins, Fat and Dachsous, and the roles they play during mammalian tissue development and disease. In Drosophila, Fat and Dachsous regulate tissue growth via the Hippo pathway and planar cell polarity (PCP). The Drosophila wing has been an ideal tissue to observe how mutations in these cadherins affect tissue development. In mammals, there are multiple Fat and Dachsous cadherins, which are expressed in many tissues, but mutations in these cadherins that affect growth and tissue organization are context dependent. Here we examine how mutations in the Fat and Dachsous mammalian genes affect development in mammals and contribute to human disease.
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Affiliation(s)
- Jennysue Kasiah
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
| | - Helen McNeill
- Department of Developmental Biology, Washington University School of Medicine in St. Louis, St. Louis, MO, United States.
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6
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Brittle A, Warrington SJ, Strutt H, Manning E, Tan SE, Strutt D. Distinct mechanisms of planar polarization by the core and Fat-Dachsous planar polarity pathways in the Drosophila wing. Cell Rep 2022; 40:111419. [PMID: 36170824 PMCID: PMC9631118 DOI: 10.1016/j.celrep.2022.111419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 11/29/2022] Open
Abstract
Planar polarity describes the coordinated polarization of cells within a tissue plane, and in animals can be determined by the “core” or Fat-Dachsous pathways. Current models for planar polarity establishment involve two components: tissue-level “global” cues that determine the overall axis of polarity and cell-level feedback-mediated cellular polarity amplification. Here, we investigate the contributions of global cues versus cellular feedback amplification in the core and Fat-Dachsous pathways during Drosophila pupal wing development. We present evidence that these pathways generate planar polarity via distinct mechanisms. Core pathway function is consistent with strong feedback capable of self-organizing cell polarity, which can then be aligned with the tissue axis via weak or transient global cues. Conversely, generation of cell polarity by the Ft-Ds pathway depends on strong global cues in the form of graded patterns of gene expression, which can then be amplified by weak feedback mechanisms. The core and Fat-Dachsous planar polarity pathways function via distinct mechanisms The core can self-organize planar polarity and be oriented by weak upstream cues Fat-Dachsous are oriented by strong gradient cues but show poor self-organization
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Affiliation(s)
- Amy Brittle
- School of Biosciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | | | - Helen Strutt
- School of Biosciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Elizabeth Manning
- School of Biosciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Su Ee Tan
- School of Biosciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - David Strutt
- School of Biosciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
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Gridnev A, Misra JR. Emerging Mechanisms of Growth and Patterning Regulation by Dachsous and Fat Protocadherins. Front Cell Dev Biol 2022; 10:842593. [PMID: 35372364 PMCID: PMC8967653 DOI: 10.3389/fcell.2022.842593] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/08/2022] [Indexed: 01/14/2023] Open
Abstract
Dachsous (Ds) and Fat are evolutionarily conserved cell adhesion molecules that play a critical role in development of multiple organ systems, where they coordinate tissue growth and morphogenesis. Much of our understanding of Ds-Fat signaling pathway comes from studies in Drosophila, where they initiate a signaling pathway that regulate growth by influencing Hippo signaling and morphogenesis by regulating Planar Cell Polarity (PCP). In this review, we discuss recent advances in our understanding of the mechanisms by which Ds-Fat signaling pathway regulates these critical developmental processes. Further, we discuss the progress in our understanding about how they function in mammals.
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8
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Strutt H, Strutt D. DAnkrd49 and Bdbt act via Casein kinase Iε to regulate planar polarity in Drosophila. PLoS Genet 2020; 16:e1008820. [PMID: 32750048 PMCID: PMC7402468 DOI: 10.1371/journal.pgen.1008820] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/19/2020] [Indexed: 11/30/2022] Open
Abstract
The core planar polarity proteins are essential mediators of tissue morphogenesis, controlling both the polarised production of cellular structures and polarised tissue movements. During development the core proteins promote planar polarisation by becoming asymmetrically localised to opposite cell edges within epithelial tissues, forming intercellular protein complexes that coordinate polarity between adjacent cells. Here we describe a novel protein complex that regulates the asymmetric localisation of the core proteins in the Drosophila pupal wing. DAnkrd49 (an ankyrin repeat protein) and Bride of Doubletime (Bdbt, a non-canonical FK506 binding protein family member) physically interact, and regulate each other’s levels in vivo. Loss of either protein results in a reduction in core protein asymmetry and disruption of the placement of trichomes at the distal edge of pupal wing cells. Post-translational modifications are thought to be important for the regulation of core protein behaviour and their sorting to opposite cell edges. Consistent with this, we find that loss of DAnkrd49 or Bdbt leads to reduced phosphorylation of the core protein Dishevelled and to decreased Dishevelled levels both at cell junctions and in the cytoplasm. Bdbt has previously been shown to regulate activity of the kinase Discs Overgrown (Dco, also known as Doubletime or Casein Kinase Iε), and Dco itself has been implicated in regulating planar polarity by phosphorylating Dsh as well as the core protein Strabismus. We demonstrate that DAnkrd49 and Bdbt act as dominant suppressors of Dco activity. These findings support a model whereby Bdbt and DAnkrd49 act together to modulate the activity of Dco during planar polarity establishment. In many animal tissues, sheets of cells are polarised in the plane of the tissue, which is evident by the production of polarised structures, such as hairs on the fly wing that point in the same direction or cilia that beat in the same direction. One group of proteins controlling this coordinated polarity are the core planar polarity proteins, which localise asymmetrically within cells such that some core proteins localise to one cell end and others to the opposite cell end. It is thought that modifications such as phosphorylation may locally regulate core protein stability, and this promotes sorting of proteins to different cell ends. We identify two proteins, DAnkrd49 and Bdbt, that form a complex and regulate core protein asymmetry. Loss of either protein causes a reduction in overall levels of the core protein Dishevelled (Dsh), and a reduction in its phosphorylation. We provide evidence that the effect on core protein asymmetry is mediated via regulation of the kinase activity of Discs overgrown (Dco, also known as Doubletime/Casein Kinase Iε) by DAnkrd49 and Bdbt. We propose that modulation of Dco activity by DAnkrd49 and Bdbt is a key step in the sorting of core proteins to opposite cell ends.
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Affiliation(s)
- Helen Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
- * E-mail: (HS); (DS)
| | - David Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, United Kingdom
- * E-mail: (HS); (DS)
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9
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Abstract
Planar cell polarization, PCP, describes a form of organization where every cell within a group acquires the same planar characteristics, whether it is orientation of cell division, direction of migration, or localization of a cellular structure. PCP is essential for correct organization of cells into tissues and building a proper body plan. Here we use Hydra, an organism with a single axis of symmetry and a very simple body plan to investigate the function of the cell adhesion molecules Fat-like and Dachsous. We show that Hydra Fat-like and Dachsous are planar polarized, providing a demonstration of planar polarization of proteins in a nonbilaterian organism. We also discover roles for Hydra Fat-like in cell adhesion, spindle orientation, and tissue organization. Fat, Fat-like, and Dachsous family cadherins are giant proteins that regulate planar cell polarity (PCP) and cell adhesion in bilaterians. Their evolutionary origin can be traced back to prebilaterian species, but their ancestral function(s) are unknown. We identified Fat-like and Dachsous cadherins in Hydra, a member of phylum Cnidaria a sister group of bilaterian. We found Hydra does not possess a true Fat homolog, but has homologs of Fat-like (HyFatl) and Dachsous (HyDs) that localize at the apical membrane of ectodermal epithelial cells and are planar polarized perpendicular to the oral–aboral axis of the animal. Using a knockdown approach we found that HyFatl is involved in local cell alignment and cell–cell adhesion, and that reduction of HyFatl leads to defects in tissue organization in the body column. Overexpression and knockdown experiments indicate that the intracellular domain (ICD) of HyFatl affects actin organization through proline-rich repeats. Thus, planar polarization of Fat-like and Dachsous cadherins has ancient, prebilaterian origins, and Fat-like cadherins have ancient roles in cell adhesion, spindle orientation, and tissue organization.
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10
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Prat‐Rojo C, Pouille P, Buceta J, Martin‐Blanco E. Mechanical coordination is sufficient to promote tissue replacement during metamorphosis in Drosophila. EMBO J 2020; 39:e103594. [PMID: 31858605 PMCID: PMC6996571 DOI: 10.15252/embj.2019103594] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/30/2019] [Accepted: 12/06/2019] [Indexed: 12/31/2022] Open
Abstract
During development, cells coordinate to organize in coherent structures. Although it is now well established that physical forces are essential for implementing this coordination, the instructive roles of mechanical inputs are not clear. Here, we show that the replacement of the larval epithelia by the adult one in Drosophila demands the coordinated exchange of mechanical signals between two cell types, the histoblasts (adult precursors) organized in nests and the surrounding larval epidermal cells (LECs). An increasing stress gradient develops from the center of the nests toward the LECs as a result of the forces generated by histoblasts as they proliferate and by the LECs as they delaminate (push/pull coordination). This asymmetric radial coordination of expansive and contractile activities contributes to epithelial replacement. Our analyses support a model in which cell-cell mechanical communication is sufficient for the rearrangements that implement epithelial morphogenesis.
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Affiliation(s)
- Carla Prat‐Rojo
- Instituto de Biología Molecular de BarcelonaConsejo Superior de Investigaciones CientíficasParc Científic de BarcelonaBarcelonaSpain
- Present address:
Nikon Instruments Europe BVAmsterdamThe Netherlands
| | - Philippe‐Alexandre Pouille
- Instituto de Biología Molecular de BarcelonaConsejo Superior de Investigaciones CientíficasParc Científic de BarcelonaBarcelonaSpain
| | - Javier Buceta
- Department of Bioengineering and Department of Chemical and Biomolecular EngineeringLehigh UniversityBethlehemPAUSA
| | - Enrique Martin‐Blanco
- Instituto de Biología Molecular de BarcelonaConsejo Superior de Investigaciones CientíficasParc Científic de BarcelonaBarcelonaSpain
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11
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Fat/Dachsous family cadherins in cell and tissue organisation. Curr Opin Cell Biol 2020; 62:96-103. [DOI: 10.1016/j.ceb.2019.10.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 09/24/2019] [Accepted: 10/16/2019] [Indexed: 02/06/2023]
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12
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Yee WB, Delaney PM, Vanderzalm PJ, Ramachandran S, Fehon RG. The CAF-1 complex couples Hippo pathway target gene expression and DNA replication. Mol Biol Cell 2019; 30:2929-2942. [PMID: 31553691 PMCID: PMC6822585 DOI: 10.1091/mbc.e19-07-0387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Hippo signaling pathway regulates tissue growth and organ development in many animals, including humans. Pathway activity leads to inactivation of Yorkie (Yki), a transcriptional coactivator that drives expression of growth-promoting genes. In addition, Yki has been shown to recruit chromatin modifiers that enhance chromatin accessibility and thereby enhance Yki function. Here, we asked whether changes in chromatin accessibility that occur during DNA replication could also affect Yki function. We found that depletion of the chromatin assembly complex-1 (CAF-1) complex, a histone chaperone that is required for nucleosome assembly after DNA replication, in the wing imaginal epithelium leads to increased Hippo pathway target gene expression but does not affect expression of other genes. Yki shows greater association with target sites when CAF-1 is depleted and misregulation of target gene expression is Yki-dependent, suggesting that nucleosome assembly competes with Yki for pathway targets post-DNA replication. Consistent with this idea, increased target gene expression is DNA replication dependent and newly replicated chromatin at target sites shows marked nucleosome depletion when CAF-1 function is reduced. These observations suggest a connection between cell cycle progression and Hippo pathway target expression, providing insights into functions of the Hippo pathway in normal and abnormal tissue growth.
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Affiliation(s)
- William B Yee
- Department of Molecular Genetics and Cell Biology.,Graduate Program in Cell and Molecular Biology, and
| | | | - Pamela J Vanderzalm
- Department of Molecular Genetics and Cell Biology.,Department of Biology, John Carroll University, University Heights, OH 44118
| | - Srinivas Ramachandran
- RNA Bioscience Initiative and.,Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045
| | - Richard G Fehon
- Department of Molecular Genetics and Cell Biology.,Graduate Program in Cell and Molecular Biology, and
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13
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Xu P, Ianes C, Gärtner F, Liu C, Burster T, Bakulev V, Rachidi N, Knippschild U, Bischof J. Structure, regulation, and (patho-)physiological functions of the stress-induced protein kinase CK1 delta (CSNK1D). Gene 2019; 715:144005. [PMID: 31376410 DOI: 10.1016/j.gene.2019.144005] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/19/2019] [Accepted: 07/23/2019] [Indexed: 12/11/2022]
Abstract
Members of the highly conserved pleiotropic CK1 family of serine/threonine-specific kinases are tightly regulated in the cell and play crucial regulatory roles in multiple cellular processes from protozoa to human. Since their dysregulation as well as mutations within their coding regions contribute to the development of various different pathologies, including cancer and neurodegenerative diseases, they have become interesting new drug targets within the last decade. However, to develop optimized CK1 isoform-specific therapeutics in personalized therapy concepts, a detailed knowledge of the regulation and functions of the different CK1 isoforms, their various splice variants and orthologs is mandatory. In this review we will focus on the stress-induced CK1 isoform delta (CK1δ), thereby addressing its regulation, physiological functions, the consequences of its deregulation for the development and progression of diseases, and its potential as therapeutic drug target.
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Affiliation(s)
- Pengfei Xu
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Chiara Ianes
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Fabian Gärtner
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Congxing Liu
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Timo Burster
- Department of Biology, School of Science and Technology, Nazarbayev University, 53 Kabanbay Batyr Ave, Nur-Sultan 020000, Kazakhstan.
| | - Vasiliy Bakulev
- Ural Federal University named after the first President of Russia B. N. Eltsin, Technology for Organic Synthesis Laboratory, 19 Mirastr., 620002 Ekaterinburg, Russia.
| | - Najma Rachidi
- Unité de Parasitologie Moléculaire et Signalisation, Department of Parasites and Insect Vectors, Institut Pasteur and INSERM U1201, 25-28 Rue du Dr Roux, 75015 Paris, France.
| | - Uwe Knippschild
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
| | - Joachim Bischof
- Department of General and Visceral Surgery, Surgery Center, Ulm University Hospital, Albert-Einstein-Allee 23, 89081 Ulm, Germany.
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Snigdha K, Gangwani KS, Lapalikar GV, Singh A, Kango-Singh M. Hippo Signaling in Cancer: Lessons From Drosophila Models. Front Cell Dev Biol 2019; 7:85. [PMID: 31231648 PMCID: PMC6558396 DOI: 10.3389/fcell.2019.00085] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/03/2019] [Indexed: 12/19/2022] Open
Abstract
Hippo pathway was initially identified through genetic screens for genes regulating organ size in fruitflies. Recent studies have highlighted the role of Hippo signaling as a key regulator of homeostasis, and in tumorigenesis. Hippo pathway is comprised of genes that act as tumor suppressor genes like hippo (hpo) and warts (wts), and oncogenes like yorkie (yki). YAP and TAZ are two related mammalian homologs of Drosophila Yki that act as effectors of the Hippo pathway. Hippo signaling deficiency can cause YAP- or TAZ-dependent oncogene addiction for cancer cells. YAP and TAZ are often activated in human malignant cancers. These transcriptional regulators may initiate tumorigenic changes in solid tumors by inducing cancer stem cells and proliferation, culminating in metastasis and chemo-resistance. Given the complex mechanisms (e.g., of the cancer microenvironment, and the extrinsic and intrinsic cues) that overpower YAP/TAZ inhibition, the molecular roles of the Hippo pathway in tumor growth and progression remain poorly defined. Here we review recent findings from studies in whole animal model organism like Drosophila on the role of Hippo signaling regarding its connection to inflammation, tumor microenvironment, and other oncogenic signaling in cancer growth and progression.
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Affiliation(s)
- Kirti Snigdha
- Department of Biology, University of Dayton, Dayton, OH, United States
| | | | - Gauri Vijay Lapalikar
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, United States
| | - Amit Singh
- Department of Biology, University of Dayton, Dayton, OH, United States.,Pre-Medical Programs, University of Dayton, Dayton, OH, United States.,Center for Tissue Regeneration and Engineering at Dayton, University of Dayton, Dayton, OH, United States.,Integrated Science and Engineering Center, University of Dayton, Dayton, OH, United States
| | - Madhuri Kango-Singh
- Department of Biology, University of Dayton, Dayton, OH, United States.,Pre-Medical Programs, University of Dayton, Dayton, OH, United States.,Center for Tissue Regeneration and Engineering at Dayton, University of Dayton, Dayton, OH, United States.,Integrated Science and Engineering Center, University of Dayton, Dayton, OH, United States
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15
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Abstract
The Hippo signal transduction pathway is an important regulator of organ growth and cell differentiation, and its deregulation contributes to the development of cancer. The activity of the Hippo pathway is strongly dependent on cell junctions, cellular architecture, and the mechanical properties of the microenvironment. In this review, we discuss recent advances in our understanding of how cell junctions transduce signals from the microenvironment and control the activity of the Hippo pathway. We also discuss how these mechanisms may control organ growth during development and regeneration, and how defects in them deregulate Hippo signaling in cancer cells.
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Affiliation(s)
- Ruchan Karaman
- VIB Center for Cancer Biology, University of Leuven, 3000 Leuven, Belgium.,Department of Oncology, University of Leuven, 3000 Leuven, Belgium
| | - Georg Halder
- VIB Center for Cancer Biology, University of Leuven, 3000 Leuven, Belgium.,Department of Oncology, University of Leuven, 3000 Leuven, Belgium
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16
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Abstract
To create an intricately patterned and reproducibly sized and shaped organ, many cellular processes must be tightly regulated. Cell elongation, migration, metabolism, proliferation rates, cell-cell adhesion, planar polarization and junctional contractions all must be coordinated in time and space. Remarkably, a pair of extremely large cell adhesion molecules called Fat (Ft) and Dachsous (Ds), acting largely as a ligand-receptor system, regulate, and likely coordinate, these many diverse processes. Here we describe recent exciting progress on how the Ds-Ft pathway controls these diverse processes, and highlight a few of the many questions remaining as to how these enormous cell adhesion molecules regulate development.
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Affiliation(s)
- Seth Blair
- Department of Integrative Biology, University of Wisconsin, Madison, USA
| | - Helen McNeill
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA; Department of Molecular Genetics, University of Toronto, Toronto, Canada; Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Canada.
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17
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Difference in Dachsous Levels between Migrating Cells Coordinates the Direction of Collective Cell Migration. Dev Cell 2017; 42:479-497.e10. [DOI: 10.1016/j.devcel.2017.08.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/19/2017] [Accepted: 07/31/2017] [Indexed: 12/21/2022]
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18
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A Kinome RNAi Screen in Drosophila Identifies Novel Genes Interacting with Lgl, aPKC, and Crb Cell Polarity Genes in Epithelial Tissues. G3-GENES GENOMES GENETICS 2017; 7:2497-2509. [PMID: 28611255 PMCID: PMC5555457 DOI: 10.1534/g3.117.043513] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In both Drosophila melanogaster and mammalian systems, epithelial structure and underlying cell polarity are essential for proper tissue morphogenesis and organ growth. Cell polarity interfaces with multiple cellular processes that are regulated by the phosphorylation status of large protein networks. To gain insight into the molecular mechanisms that coordinate cell polarity with tissue growth, we screened a boutique collection of RNAi stocks targeting the kinome for their capacity to modify Drosophila “cell polarity” eye and wing phenotypes. Initially, we identified kinase or phosphatase genes whose depletion modified adult eye phenotypes associated with the manipulation of cell polarity complexes (via overexpression of Crb or aPKC). We next conducted a secondary screen to test whether these cell polarity modifiers altered tissue overgrowth associated with depletion of Lgl in the wing. These screens identified Hippo, Jun kinase (JNK), and Notch signaling pathways, previously linked to cell polarity regulation of tissue growth. Furthermore, novel pathways not previously connected to cell polarity regulation of tissue growth were identified, including Wingless (Wg/Wnt), Ras, and lipid/Phospho-inositol-3-kinase (PI3K) signaling pathways. Additionally, we demonstrated that the “nutrient sensing” kinases Salt Inducible Kinase 2 and 3 (SIK2 and 3) are potent modifiers of cell polarity phenotypes and regulators of tissue growth. Overall, our screen has revealed novel cell polarity-interacting kinases and phosphatases that affect tissue growth, providing a platform for investigating molecular mechanisms coordinating cell polarity and tissue growth during development.
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19
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Matakatsu H, Blair SS, Fehon RG. Size does matter! Cell Cycle 2017; 16:907-908. [PMID: 28426275 DOI: 10.1080/15384101.2017.1316569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Hitoshi Matakatsu
- a Department of Molecular Genetics and Cell Biology , University of Chicago , Chicago , IL , USA
| | - Seth S Blair
- b Department of Zoology , University of Wisconsin , Madison WI , USA
| | - Richard G Fehon
- a Department of Molecular Genetics and Cell Biology , University of Chicago , Chicago , IL , USA
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20
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Pfleger CM. The Hippo Pathway: A Master Regulatory Network Important in Development and Dysregulated in Disease. Curr Top Dev Biol 2017; 123:181-228. [PMID: 28236967 DOI: 10.1016/bs.ctdb.2016.12.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Hippo Pathway is a master regulatory network that regulates proliferation, cell growth, stemness, differentiation, and cell death. Coordination of these processes by the Hippo Pathway throughout development and in mature organisms in response to diverse external and internal cues plays a role in morphogenesis, in controlling organ size, and in maintaining organ homeostasis. Given the importance of these processes, the Hippo Pathway also plays an important role in organismal health and has been implicated in a variety of diseases including eye disease, cardiovascular disease, neurodegeneration, and cancer. This review will focus on Drosophila reports that identified the core components of the Hippo Pathway revealing specific downstream biological outputs of this complicated network. A brief description of mammalian reports will complement review of the Drosophila studies. This review will also survey upstream regulation of the core components with a focus on feedback mechanisms.
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Affiliation(s)
- Cathie M Pfleger
- The Icahn School of Medicine at Mount Sinai, New York, NY, United States; The Graduate School of Biomedical Sciences, The Icahn School of Medicine at Mount Sinai, New York, NY, United States.
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21
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Abstract
Study describes how a palmitoyltransferase regulates the Hippo pathway in flies.
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22
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Keira Y, Wada M, Ishikawa HO. Regulation of Drosophila Development by the Golgi Kinase Four-Jointed. Curr Top Dev Biol 2017; 123:143-179. [DOI: 10.1016/bs.ctdb.2016.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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23
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Matakatsu H, Blair SS, Fehon RG. The palmitoyltransferase Approximated promotes growth via the Hippo pathway by palmitoylation of Fat. J Cell Biol 2016; 216:265-277. [PMID: 28031421 PMCID: PMC5223609 DOI: 10.1083/jcb.201609094] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/19/2016] [Accepted: 12/09/2016] [Indexed: 01/07/2023] Open
Abstract
The palmitoyl transferase Approximated regulates signaling by the protocadherin Fat to control tissue growth upstream of the Hippo pathway in Drosophila. Matakatsu et al. show that palmitoylation of the intracellular domain of Fat by Approximated negatively regulates Fat and its ability to restrict growth. The large protocadherin Fat functions to promote Hippo pathway activity in restricting tissue growth. Loss of Fat leads to accumulation of the atypical myosin Dachs at the apical junctional region, which in turn promotes growth by inhibiting Warts. We previously identified Approximated (App), a DHHC domain palmitoyltransferase, as a negative regulator of Fat signaling in growth control. We show here that App promotes growth by palmitoylating the intracellular domain of Fat, and that palmitoylation negatively regulates Fat function. Independently, App also recruits Dachs to the apical junctional region through protein–protein association, thereby stimulating Dachs’s activity in promoting growth. Further, we show that palmitoylation by App functions antagonistically to phosphorylation by Discs-overgrown, which activates Fat. Together, these findings suggest a model in which App promotes Dachs activity by simultaneously repressing Fat via posttranslational modification and recruiting Dachs to the apical junctional region, thereby promoting tissue growth.
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Affiliation(s)
- Hitoshi Matakatsu
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637.,Department of Zoology, University of Wisconsin, Madison, WI 53706
| | - Seth S Blair
- Department of Zoology, University of Wisconsin, Madison, WI 53706
| | - Richard G Fehon
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637
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24
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Misra JR, Irvine KD. Vamana Couples Fat Signaling to the Hippo Pathway. Dev Cell 2016; 39:254-266. [PMID: 27746048 DOI: 10.1016/j.devcel.2016.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 08/09/2016] [Accepted: 09/15/2016] [Indexed: 01/08/2023]
Abstract
The protocadherins Dachsous and Fat initiate a signaling pathway that controls growth and planar cell polarity by regulating the membrane localization of the atypical myosin Dachs. How Dachs is regulated by Fat signaling has remained unclear. Here we identify the vamana gene as playing a crucial role in regulating membrane localization of Dachs and in linking Fat and Dachsous to Dachs regulation. Vamana, an SH3-domain-containing protein, physically associates with and co-localizes with Dachs and promotes its membrane localization. Vamana also associates with the Dachsous intracellular domain and with a region of the Fat intracellular domain that is essential for controlling Hippo signaling and levels of Dachs. Epistasis experiments, structure-function analysis, and physical interaction experiments argue that Fat negatively regulates Dachs in a Vamana-dependent process. Our findings establish Vamana as a crucial component of the Dachsous-Fat pathway that transmits Fat signaling by regulating Dachs.
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Affiliation(s)
- Jyoti R Misra
- Department of Molecular Biology and Biochemistry, Howard Hughes Medical Institute, Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
| | - Kenneth D Irvine
- Department of Molecular Biology and Biochemistry, Howard Hughes Medical Institute, Waksman Institute, Rutgers University, Piscataway NJ 08854, USA.
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25
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Zhang Y, Wang X, Matakatsu H, Fehon R, Blair SS. The novel SH3 domain protein Dlish/CG10933 mediates fat signaling in Drosophila by binding and regulating Dachs. eLife 2016; 5. [PMID: 27692068 PMCID: PMC5047748 DOI: 10.7554/elife.16624] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 09/15/2016] [Indexed: 01/07/2023] Open
Abstract
Much of the Hippo and planar cell polarity (PCP) signaling mediated by the Drosophila protocadherin Fat depends on its ability to change the subcellular localization, levels and activity of the unconventional myosin Dachs. To better understand this process, we have performed a structure-function analysis of Dachs, and used this to identify a novel and important mediator of Fat and Dachs activities, a Dachs-binding SH3 protein we have named Dlish. We found that Dlish is regulated by Fat and Dachs, that Dlish also binds Fat and the Dachs regulator Approximated, and that Dlish is required for Dachs localization, levels and activity in both wild type and fat mutant tissue. Our evidence supports dual roles for Dlish. Dlish tethers Dachs to the subapical cell cortex, an effect partly mediated by the palmitoyltransferase Approximated under the control of Fat. Conversely, Dlish promotes the Fat-mediated degradation of Dachs. DOI:http://dx.doi.org/10.7554/eLife.16624.001
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Affiliation(s)
- Yifei Zhang
- Department of Zoology, University of Wisconsin-Madison, Madison, United States
| | - Xing Wang
- Department of Zoology, University of Wisconsin-Madison, Madison, United States
| | - Hitoshi Matakatsu
- Department of Zoology, University of Wisconsin-Madison, Madison, United States.,Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, United States
| | - Richard Fehon
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, United States
| | - Seth S Blair
- Department of Zoology, University of Wisconsin-Madison, Madison, United States
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26
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Badouel C, Zander MA, Liscio N, Bagherie-Lachidan M, Sopko R, Coyaud E, Raught B, Miller FD, McNeill H. Fat1 interacts with Fat4 to regulate neural tube closure, neural progenitor proliferation and apical constriction during mouse brain development. Development 2015. [PMID: 26209645 DOI: 10.1242/dev.123539] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mammalian brain development requires coordination between neural precursor proliferation, differentiation and cellular organization to create the intricate neuronal networks of the adult brain. Here, we examined the role of the atypical cadherins Fat1 and Fat4 in this process. We show that mutation of Fat1 in mouse embryos causes defects in cranial neural tube closure, accompanied by an increase in the proliferation of cortical precursors and altered apical junctions, with perturbations in apical constriction and actin accumulation. Similarly, knockdown of Fat1 in cortical precursors by in utero electroporation leads to overproliferation of radial glial precursors. Fat1 interacts genetically with the related cadherin Fat4 to regulate these processes. Proteomic analysis reveals that Fat1 and Fat4 bind different sets of actin-regulating and junctional proteins. In vitro data suggest that Fat1 and Fat4 form cis-heterodimers, providing a mechanism for bringing together their diverse interactors. We propose a model in which Fat1 and Fat4 binding coordinates distinct pathways at apical junctions to regulate neural progenitor proliferation, neural tube closure and apical constriction.
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Affiliation(s)
- Caroline Badouel
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada
| | - Mark A Zander
- Neuroscience and Mental Health Program, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Liscio
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada
| | | | - Richelle Sopko
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Etienne Coyaud
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, M5G 2M9, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, M5G 2M9, Canada
| | - Freda D Miller
- Neuroscience and Mental Health Program, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Helen McNeill
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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27
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Hale R, Brittle AL, Fisher KH, Monk NAM, Strutt D. Cellular interpretation of the long-range gradient of Four-jointed activity in the Drosophila wing. eLife 2015; 4. [PMID: 25707557 PMCID: PMC4338440 DOI: 10.7554/elife.05789] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/02/2015] [Indexed: 01/23/2023] Open
Abstract
To understand how long-range patterning gradients are interpreted at the cellular level, we investigate how a gradient of expression of the Four-jointed kinase specifies planar polarised distributions of the cadherins Fat and Dachsous in the Drosophila wing. We use computational modelling to test different scenarios for how Four-jointed might act and test the model predictions by employing fluorescence recovery after photobleaching as an in vivo assay to measure the influence of Four-jointed on Fat-Dachsous binding. We demonstrate that in vivo, Four-jointed acts both on Fat to promote its binding to Dachsous and on Dachsous to inhibit its binding to Fat, with a bias towards a stronger effect on Fat. Overall, we show that opposing gradients of Fat and Dachsous phosphorylation are sufficient to explain the observed pattern of Fat–Dachsous binding and planar polarisation across the wing, and thus demonstrate the mechanism by which a long-range gradient is interpreted. DOI:http://dx.doi.org/10.7554/eLife.05789.001 Epithelial cells form sheets that line the body surfaces and internal cavities of animals—such as the skin and the lining of the gut. Certain structures on the surface of epithelial cell sheets—for example scales, hair, and feathers—are often all orientated in a particular direction. Epithelial cells with structures organised like this are described as being ‘planar polarised’. Different proteins work together to set up planar polarity in a sheet of epithelial cells. Dachsous and Fat are two proteins that are found in the cell membranes of epithelial cells, including in the wings of the fruit fly Drosophila. These proteins bind to each other and link a cell to its neighbour. Dachsous and Fat accumulate on opposing sides of each cell: Fat accumulates on the side closest to the fly's body, and Dachsous builds up on the side closest to the wing tip. This pattern provides directional cues that help orientate surface structures, and the pattern is established, in part, by the activity of an enzyme called Four-jointed. Four-jointed adds phosphate groups onto Dachsous and Fat. The activity of the Four-jointed enzyme forms a gradient along a developing wing: levels are low near the fly's body, and high at the wing tip. Previous experiments performed on cells grown in the laboratory showed that when Four-jointed adds phosphate groups to Fat and Dachsous, it prevents Dachsous from binding to Fat. However, it also makes Fat more able to bind to Dachsous. These opposing effects are thought to cause the proteins to accumulate on opposing sides of each cell. However, this has yet to be demonstrated in real tissue, not least because of the technical difficulty of measuring whether Fat-Dachsous binding has occurred in living organisms. Here, Hale et al. overcome this challenge using a method called ‘fluorescence recovery after photobleaching’ (or FRAP) to measure Fat and Dachsous binding in the epithelial cells in the developing Drosophila wing. Combining these experimental results with a computational model confirmed the findings of previous laboratory studies: that Four-jointed makes it easier for Fat to bind to Dachsous, and makes it more difficult for Dachsous to bind to Fat. The opposing effects on the activity of Fat and Dachsous that result from the Four-jointed gradient in the developing wing are able to fully explain the observed patterns of Fat-Dachsous binding and of planar polarisation across the wing. Overall, Hale et al. demonstrate how a gradient of protein activity that spans many cells is sensed and interpreted by individual cells to establish planar polarity. However, exactly how the phosphate groups added to Dachsous and Fat by Four-jointed modifies how they bind to each other remains a question for future work. DOI:http://dx.doi.org/10.7554/eLife.05789.002
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Affiliation(s)
- Rosalind Hale
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Amy L Brittle
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | | | - Nicholas A M Monk
- School of Mathematics and Statistics, University of Sheffield, Sheffield, United Kingdom
| | - David Strutt
- Bateson Centre, University of Sheffield, Sheffield, United Kingdom
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28
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Sidorov R, Kucerova L, Kiss I, Zurovec M. Mutation in the Drosophila melanogaster adenosine receptor gene selectively decreases the mosaic hyperplastic epithelial outgrowth rates in wts or dco heterozygous flies. Purinergic Signal 2014; 11:95-105. [PMID: 25528157 DOI: 10.1007/s11302-014-9435-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 11/25/2014] [Indexed: 12/13/2022] Open
Abstract
Adenosine (Ado) is a ubiquitous metabolite that plays a prominent role as a paracrine homeostatic signal of metabolic imbalance within tissues. It quickly responds to various stress stimuli by adjusting energy metabolism and influencing cell growth and survival. Ado is also released by dead or dying cells and is present at significant concentrations in solid tumors. Ado signaling is mediated by Ado receptors (AdoR) and proteins modulating its concentration, including nucleoside transporters and Ado deaminases. We examined the impact of genetic manipulations of three Drosophila genes involved in Ado signaling on the incidence of somatic mosaic clones formed by the loss of heterozygosity (LOH) of tumor suppressor and marker genes. We show here that genetic manipulations with the AdoR, equilibrative nucleoside transporter 2 (Ent2), and Ado deaminase growth factor-A (Adgf-A) cause dramatic changes in the frequency of hyperplastic outgrowth clones formed by LOH of the warts (wts) tumor suppressor, while they have almost no effect on control yellow (y) clones. In addition, the effect of AdoR is dose-sensitive and its overexpression leads to the increase in wts hyperplastic epithelial outgrowth rates. Consistently, the frequency of mosaic hyperplastic outgrowth clones generated by the LOH of another tumor suppressor, discs overgrown (dco), belonging to the wts signaling pathway is also dependent on AdoR. Our results provide interesting insight into the maintenance of tissue homeostasis at a cellular level.
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Affiliation(s)
- Roman Sidorov
- Biology centre AS CR, Branisovska 31, 370 05, Ceske Budejovice, Czech Republic
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29
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Rodrigues-Campos M, Thompson BJ. The ubiquitin ligase FbxL7 regulates the Dachsous-Fat-Dachs system in Drosophila. Development 2014; 141:4098-103. [PMID: 25256343 PMCID: PMC4302899 DOI: 10.1242/dev.113498] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 08/22/2014] [Indexed: 11/20/2022]
Abstract
The atypical cadherins Dachsous (Ds) and Fat (Ft) are required to control the size and shape of tissues and organs in animals. In Drosophila, a key effector of Ds and Ft is the atypical myosin Dachs, which becomes planar polarised along the proximal-distal axis in developing epithelia to regulate tissue size via the Hippo pathway and tissue shape via modulating tension at junctions. How Ds and Ft control Dachs polarisation remains unclear. Here, we identify a ubiquitin ligase, FbxL7, as a novel component of the Ds-Ft-Dachs system that is required to control the level and localisation of Dachs. Loss of FbxL7 results in accumulation of Dachs, similar to loss of Ft. Overexpression of FbxL7 causes downregulation of Dachs, similar to overexpression of the Ft intracellular domain. In addition to regulating Dachs, FbxL7 also influences Ds in a similar manner. GFP-tagged FbxL7 localises to the plasma membrane in a Ft-dependent manner and is planar polarised. We propose that Ft recruits FbxL7 to the proximal side of the cell to help restrict Ds and Dachs to the distal side of the cell.
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Affiliation(s)
- Mariana Rodrigues-Campos
- Cancer Research UK - London Research Institute, Lincoln's Inn Fields, London WC2A 3LY, UK GABBA, ICBAS, Universidade do Porto, 4050-313 Porto, Portugal
| | - Barry J Thompson
- Cancer Research UK - London Research Institute, Lincoln's Inn Fields, London WC2A 3LY, UK
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30
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Kwon HJ, Waghmare I, Verghese S, Singh A, Singh A, Kango-Singh M. Drosophila C-terminal Src kinase regulates growth via the Hippo signaling pathway. Dev Biol 2014; 397:67-76. [PMID: 25446534 DOI: 10.1016/j.ydbio.2014.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/15/2014] [Accepted: 10/14/2014] [Indexed: 12/11/2022]
Abstract
The Hippo signaling pathway is involved in regulating tissue size by inhibiting cell proliferation and promoting apoptosis. Aberrant Hippo pathway function is often detected in human cancers and correlates with poor prognosis. The Drosophila C-terminal Src kinase (d-Csk) is a genetic modifier of warts (wts), a tumor-suppressor gene in the Hippo pathway, and interacts with the Src oncogene. Reduction in d-Csk expression and the consequent activation of Src are frequently seen in several cancers including hepatocellular and colorectal tumors. Previous studies show that d-Csk regulates cell proliferation and tissue size during development. Given the similarity in the loss-of-function phenotypes of d-Csk and wts, we have investigated the interactions of d-Csk with the Hippo pathway. Here we present multiple lines of evidence suggesting that d-Csk regulates growth via the Hippo signaling pathway. We show that loss of dCsk caused increased Yki activity, and our genetic epistasis places dCsk downstream of Dachs. Furthermore, dCsk requires Yki for its growth regulatory functions, suggesting that dCsk is another upstream member of the network of genes that interact to regulate Wts and its effector Yki in the Hippo signaling pathway.
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Affiliation(s)
- Hailey J Kwon
- Department of Biology, University of Dayton, Dayton, OH 45469, USA
| | | | - Shilpi Verghese
- Department of Biology, University of Dayton, Dayton, OH 45469, USA
| | - Aditi Singh
- Centerville High School, Centerville, OH 45459, USA
| | - Amit Singh
- Department of Biology, University of Dayton, Dayton, OH 45469, USA; Center for Tissue Regeneration and Engineering at Dayton, Dayton, OH 45469, USA; Premedical Programs, University of Dayton, Dayton, OH 45469, USA
| | - Madhuri Kango-Singh
- Department of Biology, University of Dayton, Dayton, OH 45469, USA; Center for Tissue Regeneration and Engineering at Dayton, Dayton, OH 45469, USA; Premedical Programs, University of Dayton, Dayton, OH 45469, USA.
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31
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Huang Y, McNeil GP, Jackson FR. Translational regulation of the DOUBLETIME/CKIδ/ε kinase by LARK contributes to circadian period modulation. PLoS Genet 2014; 10:e1004536. [PMID: 25211129 PMCID: PMC4161311 DOI: 10.1371/journal.pgen.1004536] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 06/12/2014] [Indexed: 12/02/2022] Open
Abstract
The Drosophila homolog of Casein Kinase I δ/ε, DOUBLETIME (DBT), is required for Wnt, Hedgehog, Fat and Hippo signaling as well as circadian clock function. Extensive studies have established a critical role of DBT in circadian period determination. However, how DBT expression is regulated remains largely unexplored. In this study, we show that translation of dbt transcripts are directly regulated by a rhythmic RNA-binding protein (RBP) called LARK (known as RBM4 in mammals). LARK promotes translation of specific alternative dbt transcripts in clock cells, in particular the dbt-RC transcript. Translation of dbt-RC exhibits circadian changes under free-running conditions, indicative of clock regulation. Translation of a newly identified transcript, dbt-RE, is induced by light in a LARK-dependent manner and oscillates under light/dark conditions. Altered LARK abundance affects circadian period length, and this phenotype can be modified by different dbt alleles. Increased LARK delays nuclear degradation of the PERIOD (PER) clock protein at the beginning of subjective day, consistent with the known role of DBT in PER dynamics. Taken together, these data support the idea that LARK influences circadian period and perhaps responses of the clock to light via the regulated translation of DBT. Our study is the first to investigate translational control of the DBT kinase, revealing its regulation by LARK and a novel role of this RBP in Drosophila circadian period modulation. The CKI family of serine/threonine kinase regulates diverse cellular processes, through binding to and phosphorylation of a variety of protein substrates. In mammals, mutations in two members of the family, CKIε and CKIδ were found to affect circadian period length, causing phenotypes such as altered circadian period in rodents and the Familial Advanced Sleep Phase Syndrome (FASPS) in human. The Drosophila CKI δ/ε homolog DOUBLETIME (DBT) is known to have important roles in development and circadian clock function. Despite extensive studies of DBT function, little is known about how its expression is regulated. In a previous genome-wide study, we identified dbt mRNAs as potential targets of the LARK RBP. Here we describe a detailed study of the regulation of DBT expression by LARK. We found that LARK binds to and regulates translation of dbt mRNA, promoting expression of a smaller isoform; we suggest this regulatory mechanism contributes to circadian period determination. In addition, we have identified a dbt mRNA that exhibits light-induced changes in translational status, in a LARK-dependent manner. Our study is the first to analyze the translational regulation of DBT, setting the stage for similar studies in other contexts and model systems.
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Affiliation(s)
- Yanmei Huang
- Department of Neuroscience, Sackler School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Gerard P McNeil
- Department of Biology, York College, Jamaica, New York, New York, United States of America
| | - F Rob Jackson
- Department of Neuroscience, Sackler School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, United States of America
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The Atypical Cadherin Fat Directly Regulates Mitochondrial Function and Metabolic State. Cell 2014; 158:1293-1308. [DOI: 10.1016/j.cell.2014.07.036] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/09/2014] [Accepted: 07/10/2014] [Indexed: 11/21/2022]
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Sadeqzadeh E, de Bock CE, O'Donnell MR, Timofeeva A, Burns GF, Thorne RF. FAT1 cadherin is multiply phosphorylated on its ectodomain but phosphorylation is not catalysed by the four-jointed homologue. FEBS Lett 2014; 588:3511-7. [PMID: 25150169 DOI: 10.1016/j.febslet.2014.08.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 08/11/2014] [Indexed: 01/15/2023]
Abstract
The interaction between the Drosophila cadherins fat and dachsous is regulated by phosphorylation of their respective ectodomains, a process catalysed by the atypical kinase four-jointed. Given that many signalling functions are conserved between Drosophila and vertebrate Fat cadherins, we sought to determine whether ectodomain phosphorylation is conserved in FAT1 cadherin, and also whether FJX1, the vertebrate orthologue of four-jointed, was involved in such phosphorylation events. Potential Fj consensus phosphorylation motifs were identified in FAT1 and biochemical experiments revealed the presence of phosphoserine and phosphothreonine residues in its extracellular domain. However, silencing FJX1 did not influence the levels of FAT1 ectodomain phosphorylation, indicating that other mechanisms are likely responsible.
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Affiliation(s)
- Elham Sadeqzadeh
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
| | - Charles E de Bock
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Maureen R O'Donnell
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Anna Timofeeva
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Gordon F Burns
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
| | - Rick F Thorne
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia; School of Environmental & Life Sciences, University of Newcastle, Ourimbah, NSW 2258, Australia.
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Bosch JA, Sumabat TM, Hafezi Y, Pellock BJ, Gandhi KD, Hariharan IK. The Drosophila F-box protein Fbxl7 binds to the protocadherin fat and regulates Dachs localization and Hippo signaling. eLife 2014; 3:e03383. [PMID: 25107277 PMCID: PMC4144329 DOI: 10.7554/elife.03383] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The Drosophila protocadherin Fat (Ft) regulates growth, planar cell polarity (PCP) and proximodistal patterning. A key downstream component of Ft signaling is the atypical myosin Dachs (D). Multiple regions of the intracellular domain of Ft have been implicated in regulating growth and PCP but how Ft regulates D is not known. Mutations in Fbxl7, which encodes an F-box protein, result in tissue overgrowth and abnormalities in proximodistal patterning that phenocopy deleting a specific portion of the intracellular domain (ICD) of Ft that regulates both growth and PCP. Fbxl7 binds to this same portion of the Ft ICD, co-localizes with Ft to the proximal edge of cells and regulates the levels and asymmetry of D at the apical membrane. Fbxl7 can also regulate the trafficking of proteins between the apical membrane and intracellular vesicles. Thus Fbxl7 functions in a subset of pathways downstream of Ft and links Ft to D localization. DOI:http://dx.doi.org/10.7554/eLife.03383.001 Multi-cellular organisms are made up of cells that are organized into tissues and organs that reach a predictable size and shape at the end of their development. To do this, cells must be able to sense their position and orientation within the body and know when to stop growing. Epithelial cells—which make up the outer surface of an animal's body and line the cavities of its internal organs—connect to each other to form flat sheets. These sheets of cells contain structures that are oriented along the plane of the sheet. However, how this so-called ‘planar cell polarity’ coordinates with cell growth in order to build complex tissues and organs remains to be discovered. A protein called Fat is a major player in both planar cell polarity and the Hippo signaling pathway, which controls cell growth. As such, the Fat protein appears to be crucial for controlling the size and shape of organs. Mutations in the Fat protein cause massive tissue overgrowth, prevent planar cell polarity being established correctly, and stop the legs and wings of fruit flies developing normally. The Fat protein also plays a role in distributing another protein called Dachs—which is also part of the Hippo signaling pathway. In epithelial cells of the developing wing, Dachs is mostly located on the side of the cell that is closest to the tip of the developing wing (the so-called ‘distal surface’). How Fat and Dachs work together is not understood, but it is known that they do not bind to each other directly. Now, Bosch et al. show that in the fruit fly Drosophila, the Fat protein binds to another protein called Fbxl7. Flies that cannot produce working Fbxl7 have defects in some aspects of planar cell polarity and a modest increase in tissue growth. Fbxl7 seems to account for part, but not all, of the ability of Fat to restrict tissue growth. Furthermore, a lack of the Fbxl7 protein results in a spreading of Dachs protein across the apical surface—which faces out of the epithelial sheet—of epithelial cells. On the other hand, if Fbxl7 is over-expressed, Dachs is driven to the interior of each cell. Hence, a normal level of Fbxl7 protein restricts the Dachs protein to the correct parts of the cell surface. Together, the findings of Bosch et al. show that the Fbxl7 protein is a key link between the Fat and Dachs proteins. These results also provide an understanding of how growth and planar cell polarity—two processes that are essential for normal development of all multi-cellular organisms—are coordinated. DOI:http://dx.doi.org/10.7554/eLife.03383.002
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Affiliation(s)
- Justin A Bosch
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Taryn M Sumabat
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Yassi Hafezi
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Brett J Pellock
- Department of Biology, Providence College, Providence, United States
| | - Kevin D Gandhi
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Iswar K Hariharan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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Gold KS, Brand AH. Optix defines a neuroepithelial compartment in the optic lobe of the Drosophila brain. Neural Dev 2014; 9:18. [PMID: 25074684 PMCID: PMC4127074 DOI: 10.1186/1749-8104-9-18] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 06/25/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND During early brain development, the organisation of neural progenitors into a neuroepithelial sheet maintains tissue integrity during growth. Neuroepithelial cohesion and patterning is essential for orderly proliferation and neural fate specification. Neuroepithelia are regionalised by the expression of transcription factors and signalling molecules, resulting in the formation of distinct developmental, and ultimately functional, domains. RESULTS We have discovered that the Six3/6 family orthologue Optix is an essential regulator of neuroepithelial maintenance and patterning in the Drosophila brain. Six3 and Six6 are required for mammalian eye and forebrain development, and mutations in humans are associated with severe eye and brain malformation. In Drosophila, Optix is expressed in a sharply defined region of the larval optic lobe, and its expression is reciprocal to that of the transcription factor Vsx1. Optix gain- and loss-of-function affects neuroepithelial adhesion, integrity and polarity. We find restricted cell lineage boundaries that correspond to transcription factor expression domains. CONCLUSION We propose that the optic lobe is compartmentalised by expression of Optix and Vsx1. Our findings provide insight into the spatial patterning of a complex region of the brain, and suggest an evolutionarily conserved principle of visual system development.
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Affiliation(s)
| | - Andrea H Brand
- The Gurdon Institute and Department of Physiology, Development & Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.
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36
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Abstract
Planar cell polarity (PCP) in epithelia, orthogonal to the apical-basal axis, is essential for numerous developmental events and physiological functions. Drosophila model systems have been at the forefront of studies revealing insights into mechanisms regulating PCP and have revealed distinct signaling modules. One of these, involving the atypical cadherins Fat and Dachsous and the ectokinase Four-jointed, appears to link the direction of cell polarization to the tissue axes. We discuss models for the function of this signaling module as well as several unanswered questions that may guide future investigations.
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Affiliation(s)
- Maja Matis
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA
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37
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Abstract
The Hippo pathway is a kinase cascade, formed by Hippo, Salvador, Warts, and Mats, that regulates the subcellular distribution and transcriptional activity of Yorkie. Yorkie is a transcriptional coactivator that promotes the expression of genes that inhibit apoptosis and drive cell proliferation. We review recent studies indicating that activity of the Hippo pathway is controlled by cell-cell junctions, cell adhesion molecules, scaffolding proteins, and cytoskeletal proteins, as well as by regulators of apical-basal polarity and extracellular tension.
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Affiliation(s)
- Leonie Enderle
- 1Biozentrum, University of Basel, 4056 Basel, Switzerland
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38
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Cappello S, Gray MJ, Badouel C, Lange S, Einsiedler M, Srour M, Chitayat D, Hamdan FF, Jenkins ZA, Morgan T, Preitner N, Uster T, Thomas J, Shannon P, Morrison V, Di Donato N, Van Maldergem L, Neuhann T, Newbury-Ecob R, Swinkells M, Terhal P, Wilson LC, Zwijnenburg PJG, Sutherland-Smith AJ, Black MA, Markie D, Michaud JL, Simpson MA, Mansour S, McNeill H, Götz M, Robertson SP. Mutations in genes encoding the cadherin receptor-ligand pair DCHS1 and FAT4 disrupt cerebral cortical development. Nat Genet 2013; 45:1300-8. [DOI: 10.1038/ng.2765] [Citation(s) in RCA: 182] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Accepted: 08/26/2013] [Indexed: 02/08/2023]
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Tissir F, Goffinet AM. Shaping the nervous system: role of the core planar cell polarity genes. Nat Rev Neurosci 2013; 14:525-35. [PMID: 23839596 DOI: 10.1038/nrn3525] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Planar cell polarity (PCP) is complementary to the intrinsic polarization of single cells and refers to the global coordination of cell behaviour in the plane of a tissue and, by extension, to the signalling pathways that control it. PCP is most evident in cell sheets, and research into PCP was for years confined to studies in Drosophila melanogaster. However, PCP has more recently emerged as an important phenomenon in vertebrates, in which it regulates various developmental processes and is associated with multiple disorders. In particular, core PCP genes are crucial for the development and function of the nervous system. They are involved in neural tube closure, ependymal polarity, neuronal migration, dendritic growth and axon guidance.
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Affiliation(s)
- Fadel Tissir
- University of Louvain, Institute of Neuroscience, Developmental Neurobiology Group, Avenue Mounier 73, Box B1.73.16, 1200 Brussels, Belgium
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Caruso N, Herberth B, Bartoli M, Puppo F, Dumonceaux J, Zimmermann A, Denadai S, Lebossé M, Roche S, Geng L, Magdinier F, Attarian S, Bernard R, Maina F, Levy N, Helmbacher F. Deregulation of the protocadherin gene FAT1 alters muscle shapes: implications for the pathogenesis of facioscapulohumeral dystrophy. PLoS Genet 2013; 9:e1003550. [PMID: 23785297 PMCID: PMC3681729 DOI: 10.1371/journal.pgen.1003550] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 04/23/2013] [Indexed: 01/01/2023] Open
Abstract
Generation of skeletal muscles with forms adapted to their function is essential for normal movement. Muscle shape is patterned by the coordinated polarity of collectively migrating myoblasts. Constitutive inactivation of the protocadherin gene Fat1 uncoupled individual myoblast polarity within chains, altering the shape of selective groups of muscles in the shoulder and face. These shape abnormalities were followed by early onset regionalised muscle defects in adult Fat1-deficient mice. Tissue-specific ablation of Fat1 driven by Pax3-cre reproduced muscle shape defects in limb but not face muscles, indicating a cell-autonomous contribution of Fat1 in migrating muscle precursors. Strikingly, the topography of muscle abnormalities caused by Fat1 loss-of-function resembles that of human patients with facioscapulohumeral dystrophy (FSHD). FAT1 lies near the critical locus involved in causing FSHD, and Fat1 mutant mice also show retinal vasculopathy, mimicking another symptom of FSHD, and showed abnormal inner ear patterning, predictive of deafness, reminiscent of another burden of FSHD. Muscle-specific reduction of FAT1 expression and promoter silencing was observed in foetal FSHD1 cases. CGH array-based studies identified deletion polymorphisms within a putative regulatory enhancer of FAT1, predictive of tissue-specific depletion of FAT1 expression, which preferentially segregate with FSHD. Our study identifies FAT1 as a critical determinant of muscle form, misregulation of which associates with FSHD.
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Affiliation(s)
- Nathalie Caruso
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Balàzs Herberth
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Marc Bartoli
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
| | - Francesca Puppo
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
| | - Julie Dumonceaux
- INSERM U974, UMR 7215 CNRS, Institut de Myologie, UM 76 Université Pierre et Marie Curie, Paris, France
| | - Angela Zimmermann
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Simon Denadai
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Marie Lebossé
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Stephane Roche
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
| | - Linda Geng
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Frederique Magdinier
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
| | - Shahram Attarian
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
- AP-HM, Neurologie, maladies neuro-musculaires, Hôpital de la Timone, Marseille, France
| | - Rafaelle Bernard
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
- AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, Marseille, France
| | - Flavio Maina
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Nicolas Levy
- Aix-Marseille Université, Faculté de Médecine de la Timone, INSERM UMR 910, Marseille, France
- AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, Marseille, France
| | - Françoise Helmbacher
- Aix-Marseille Université, CNRS, IBDML UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
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Sadeqzadeh E, de Bock CE, Thorne RF. Sleeping giants: emerging roles for the fat cadherins in health and disease. Med Res Rev 2013; 34:190-221. [PMID: 23720094 DOI: 10.1002/med.21286] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The vertebrate Fat cadherins comprise a small gene family of four members, Fat1-Fat4, all closely related in structure to Drosophila ft and ft2. Over the past decade, knock-out mouse studies, genetic manipulation, and large sequencing projects has aided our understanding of the function of vertebrate Fat cadherins in tissue development and disease. The majority of studies of this family have focused on Fat1, with evidence now showing it can bind enable (ENA)/Vasodilator-stimulated phosphoprotein (VASP), β-catenin and Atrophin proteins to influence cell polarity and motility; HOMER-1 and HOMER-3 proteins to regulate actin accumulation in neuronal synapses; and scribble to influence the Hippo signaling pathway. Fat2 and Fat3 can regulate cell migration in a tissue specific manner and Fat4 appears to influence both planar cell polarity and Hippo signaling recapitulating the activity of Drosophila ft. Knowledge about the exact downstream signaling pathways activated by each family member remains in its infancy, but it is becoming clearer that they have tissue specific and redundant roles in development and may be lost or gained in cancer. In this review, we summarize the recent progress on understanding the role of the Fat cadherin family, integrating the current knowledge of molecular interactions and tissue distributions, together with the accumulating evidence of their changed expression in human disease. The latter is now beginning to promote interest in these molecules as both biomarkers and new targets for therapeutic intervention.
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Affiliation(s)
- Elham Sadeqzadeh
- Cancer Research Unit, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW, 2305, Australia
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42
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Zhao X, Yang CH, Simon MA. The Drosophila Cadherin Fat regulates tissue size and planar cell polarity through different domains. PLoS One 2013; 8:e62998. [PMID: 23667559 PMCID: PMC3647076 DOI: 10.1371/journal.pone.0062998] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 04/01/2013] [Indexed: 01/15/2023] Open
Abstract
The Drosophila Cadherin Fat (Ft) has been identified as a crucial regulator of tissue size and Planar Cell Polarity (PCP). However, the precise mechanism by which Ft regulates these processes remains unclear. In order to advance our understanding of the action of Ft, we have sought to identify the crucial Ft effector domains. Here we report that a small region of the Ft cytoplasmic domain (H2 region) is both necessary and sufficient, when membrane localized, to support viability and prevent tissue overgrowth. Interestingly, the H2 region is dispensable for regulating PCP signaling, whereas the mutant Ft lacking the H2 region is fully capable of directing PCP. This result suggests that Ft's roles in PCP signaling and tissue size control are separable, and each can be carried out independently. Surprisingly, the crucial regions of Ft identified in our structure-function study do not overlap with the previously reported interaction regions with Atrophin, Dco, or Lowfat.
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Affiliation(s)
- Xuesong Zhao
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Chung-hui Yang
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Michael A. Simon
- Department of Biology, Stanford University, Stanford, California, United States of America
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43
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Abstract
Control of cell number is crucial in animal development and tissue homeostasis, and its dysregulation may result in tumor formation or organ degeneration. The Hippo pathway in both Drosophila and mammals regulates cell number by modulating cell proliferation, cell death, and cell differentiation. Recently, numerous upstream components involved in the Hippo pathway have been identified, such as cell polarity, mechanotransduction, and G-protein-coupled receptor (GPCR) signaling. Actin cytoskeleton or cellular tension appears to be the master mediator that integrates and transmits upstream signals to the core Hippo signaling cascade. Here, we review regulatory mechanisms of the Hippo pathway and discuss potential implications involved in different physiological and pathological conditions.
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Affiliation(s)
- Fa-Xing Yu
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, 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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44
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Pan G, Feng Y, Ambegaonkar AA, Sun G, Huff M, Rauskolb C, Irvine KD. Signal transduction by the Fat cytoplasmic domain. Development 2013; 140:831-42. [PMID: 23318637 DOI: 10.1242/dev.088534] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The large atypical cadherin Fat is a receptor for both Hippo and planar cell polarity (PCP) pathways. Here we investigate the molecular basis for signal transduction downstream of Fat by creating targeted alterations within a genomic construct that contains the entire fat locus, and by monitoring and manipulating the membrane localization of the Fat pathway component Dachs. We establish that the human Fat homolog FAT4 lacks the ability to transduce Hippo signaling in Drosophila, but can transduce Drosophila PCP signaling. Targeted deletion of conserved motifs identifies a four amino acid C-terminal motif that is essential for aspects of Fat-mediated PCP, and other internal motifs that contribute to Fat-Hippo signaling. Fat-Hippo signaling requires the Drosophila Casein kinase 1ε encoded by discs overgrown (Dco), and we characterize candidate Dco phosphorylation sites in the Fat intracellular domain (ICD), the mutation of which impairs Fat-Hippo signaling. Through characterization of Dachs localization and directed membrane targeting of Dachs, we show that localization of Dachs influences both the Hippo and PCP pathways. Our results identify a conservation of Fat-PCP signaling mechanisms, establish distinct functions for different regions of the Fat ICD, support the correlation of Fat ICD phosphorylation with Fat-Hippo signaling, and confirm the importance of Dachs membrane localization to downstream signaling pathways.
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Affiliation(s)
- Guohui Pan
- Howard Hughes Medical Institute, Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers The State University of New Jersey, Piscataway, NJ 08854, USA.
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45
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Sharma P, McNeill H. Fat and Dachsous cadherins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 116:215-35. [PMID: 23481197 DOI: 10.1016/b978-0-12-394311-8.00010-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fat and Dachsous (Ds) are very large cell adhesion molecules. They bind each other and have important, highly conserved roles in planar cell polarity (PCP) and growth control. PCP is defined as the directionally coordinated development of cellular structures or behavior. Cellular and tissue growth needs to be modulated in terms of rate and final size, and the Hippo pathway regulates growth in a variety of developmental contexts. Fat and Ds are important upstream regulators of these pathways. There are two Fat proteins in Drosophila, Fat and Fat2, and four in vertebrates, Fat1-4. There is one Ds protein in Drosophila and two in vertebrates, Dachsous1-2. In this chapter, we discuss the roles of Fat and Ds family members, focusing on Drosophila and mouse development.
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46
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Verghese S, Waghmare I, Kwon H, Hanes K, Kango-Singh M. Scribble acts in the Drosophila fat-hippo pathway to regulate warts activity. PLoS One 2012; 7:e47173. [PMID: 23144804 PMCID: PMC3489842 DOI: 10.1371/journal.pone.0047173] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 09/10/2012] [Indexed: 01/15/2023] Open
Abstract
Epithelial cells are the major cell-type for all organs in multicellular organisms. In order to achieve correct organ size, epithelial tissues need mechanisms that limit their proliferation, and protect tissues from damage caused by defective epithelial cells. Recently, the Hippo signaling pathway has emerged as a major mechanism that orchestrates epithelial development. Hippo signaling is required for cells to stop proliferation as in the absence of Hippo signaling tissues continue to proliferate and produce overgrown organs or tumors. Studies in Drosophila have led the way in providing a framework for how Hippo alters the pattern of gene transcription in target cells, leading to changes in cell proliferation, survival, and other behaviors. Scribble (Scrib) belongs to a class of neoplastic tumor suppressor genes that are required to establish apical-basal cell polarity. The disruption of apical-basal polarity leads to uncontrolled cell proliferation of epithelial cells. The interaction of apical basal polarity genes with the Hippo pathway has been an area of intense investigation. Loss of scrib has been known to affect Hippo pathway targets, however, its functions in the Hippo pathway still remain largely unknown. We investigated the interactions of Scrib with the Hippo pathway. We present data suggesting that Drosophila scrib acts downstream of the Fat (Ft) receptor, and requires Hippo signaling for its growth regulatory functions. We show that Ft requires Scrib to interact with Expanded (Ex) and Dachs (D), and for regulating Warts (Wts) levels and stability, thus placing Scrib in the Hippo pathway network.
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Affiliation(s)
- Shilpi Verghese
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Indrayani Waghmare
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Hailey Kwon
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Katelin Hanes
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
| | - Madhuri Kango-Singh
- Department of Biology, University of Dayton, Dayton, Ohio, United States of America
- Pre-Medical Programs, University of Dayton, Dayton, Ohio, United States of America
- Center for Tissue Regeneration and Engineering at Dayton, University of Dayton, Dayton, Ohio, United States of America
- * E-mail:
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Shingleton AW. The regulation of organ size in Drosophila: physiology, plasticity, patterning and physical force. Organogenesis 2012; 6:76-87. [PMID: 20885854 DOI: 10.4161/org.6.2.10375] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 10/16/2009] [Accepted: 10/20/2009] [Indexed: 12/19/2022] Open
Abstract
The correct regulation of organ size is a fundamental developmental process, the failure of which can compromise organ function and organismal integrity. Consequently, the mechanisms that regulate organ size have been subject to intense research. This research has highlighted four classes of mechanism that are involved in organ size regulation: physiology, plasticity, patterning and physical force. Nevertheless, how these mechanisms are integrated and converge on the cellular process that regulate organ growth is unknown. One group of animals where this integration is beginning to be achieved is in the insects. Here, I review the different mechanisms that regulate organ size in insects, and describe our current understanding of how these mechanisms interact. The genes and hormones involved are remarkably conserved in all animals, so these studies in insects provide a precedent for future research on organ size regulation in mammals.
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Ambegaonkar AA, Pan G, Mani M, Feng Y, Irvine KD. Propagation of Dachsous-Fat planar cell polarity. Curr Biol 2012; 22:1302-8. [PMID: 22727698 DOI: 10.1016/j.cub.2012.05.049] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 05/09/2012] [Accepted: 05/29/2012] [Indexed: 01/27/2023]
Abstract
The Fat pathway controls both planar cell polarity (PCP) and organ growth. Fat signaling is regulated by the graded expression of the Fat ligand Dachsous (Ds) and the cadherin-domain kinase Four-jointed (Fj). The vectors of these gradients influence PCP, whereas their slope can influence growth. The Fj and Ds gradients direct the polarized membrane localization of the myosin Dachs, which is a crucial downstream component of Fat signaling. Here we show that repolarization of Dachs by differential expression of Fj or Ds can propagate through the wing disc, which indicates that Fj and Ds gradients can be measured over long range. Through characterization of tagged genomic constructs, we show that Ds and Fat are themselves partially polarized along the endogenous Fj and Ds gradients, providing a mechanism for propagation of PCP within the Fat pathway. We also identify a biochemical mechanism that might contribute to this polarization by showing that Ds is subject to endoproteolytic cleavage and that the relative levels of Ds isoforms are modulated by Fat.
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Affiliation(s)
- Abhijit A Ambegaonkar
- Howard Hughes Medical Institute, Waksman Institute and Department of Molecular Biology and Biochemistry, Rutgers-The State University of New Jersey, Piscataway, NJ 08854, USA
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The Hippo pathway regulates stem cell proliferation, self-renewal, and differentiation. Protein Cell 2012; 3:291-304. [PMID: 22549587 DOI: 10.1007/s13238-012-2919-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 03/15/2012] [Indexed: 12/16/2022] Open
Abstract
Stem cells and progenitor cells are the cells of origin for multi-cellular organisms and organs. They play key roles during development and their dysregulation gives rise to human diseases such as cancer. The recent development of induced pluripotent stem cell (iPSC) technology which converts somatic cells to stem-like cells holds great promise for regenerative medicine. Nevertheless, the understanding of proliferation, differentiation, and self-renewal of stem cells and organ-specific progenitor cells is far from clear. Recently, the Hippo pathway was demonstrated to play important roles in these processes. The Hippo pathway is a newly established signaling pathway with critical functions in limiting organ size and suppressing tumorigenesis. This pathway was first found to inhibit cell proliferation and promote apoptosis, therefore regulating cell number and organ size in both Drosophila and mammals. However, in several organs, disturbance of the pathway leads to specific expansion of the progenitor cell compartment and manipulation of the pathway in embryonic stem cells strongly affects their self-renewal and differentiation. In this review, we summarize current observations on roles of the Hippo pathway in different types of stem cells and discuss how these findings changed our view on the Hippo pathway in organ development and tumorigenesis.
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Matakatsu H, Blair SS. Separating planar cell polarity and Hippo pathway activities of the protocadherins Fat and Dachsous. Development 2012; 139:1498-508. [PMID: 22399682 DOI: 10.1242/dev.070367] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The giant Drosophila protocadherin Fat (Ft) affects planar cell polarity (PCP). Ft also inhibits the overgrowth of imaginal discs via the Hippo pathway, repressing the activity of the transcription co-factor Yorkie (Yki). Much of Ft activity is likely to be mediated by its intracellular domain (Ft ICD). However, the links between the Ft ICD and either PCP or Hippo activity are poorly understood, and the role of the Hippo pathway in PCP is ambiguous. We have performed a structure-function analysis of the Ft ICD. We found that the effects of the Ft ICD on PCP and the Hippo pathway are largely separable. Surprisingly, the domains required for PCP and Hippo activities do not map to any of the previously identified protein interaction domains, nor, with one exception, to the regions that are highly conserved in mammalian Fat4. We also found that the extracellular domain of Ft can act independently of the Ft ICD in PCP and can trigger dominant-negative and boundary effects on Hippo activity, probably via binding to the protocadherin Dachsous.
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Affiliation(s)
- Hitoshi Matakatsu
- Department of Zoology, University of Wisconsin-Madison, 250 North Mills Street, Madison, WI 53706, USA
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