1
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Matakatsu H, Fehon RG. Dachsous and Fat coordinately repress the Dachs-Dlish-Approximated complex to control growth. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.18.599638. [PMID: 38948705 PMCID: PMC11212998 DOI: 10.1101/2024.06.18.599638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Two protocadherins, Dachsous (Ds) and Fat (Ft), regulate organ growth in Drosophila via the Hippo pathway. Ds and Ft bind heterotypically to regulate the abundance and subcellular localization of a 'core complex' consisting of Dachs, Dlish and Approximated. This complex localizes to the junctional cortex where it promotes growth by repressing the pathway kinase Warts. Ds is believed to promote growth by recruiting and stabilizing the core complex at the junctional cortex, while Ft represses growth by promoting degradation of core complex components. Here, we examine the functions of intracellular domains of Ds and Ft and their relationship to the core complex. While Ds promotes accumulation of the core complex proteins in cortical puncta, it is not required for core complex assembly. Indeed, the core complex assembles maximally in the absence of both Ds and Ft. Furthermore, while Ds promotes growth in the presence of Ft, it represses growth in the absence of Ft by removing the core complex from the junctional cortex. Ft similarly recruits core complex components, however it normally promotes their degradation. Our findings reveal that Ds and Ft constrain tissue growth by repressing the default 'on' state of the core complex.
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2
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Tokamov SA, Buiter S, Ullyot A, Scepanovic G, Williams AM, Fernandez-Gonzalez R, Horne-Badovinac S, Fehon RG. Cortical tension promotes Kibra degradation via Par-1. Mol Biol Cell 2024; 35:ar2. [PMID: 37903240 PMCID: PMC10881160 DOI: 10.1091/mbc.e23-06-0246] [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: 06/26/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 11/01/2023] Open
Abstract
The Hippo pathway is an evolutionarily conserved regulator of tissue growth. Multiple Hippo signaling components are regulated via proteolytic degradation. However, how these degradation mechanisms are themselves modulated remains unexplored. Kibra is a key upstream pathway activator that promotes its own ubiquitin-mediated degradation upon assembling a Hippo signaling complex. Here, we demonstrate that Hippo complex-dependent Kibra degradation is modulated by cortical tension. Using classical genetic, osmotic, and pharmacological manipulations of myosin activity and cortical tension, we show that increasing cortical tension leads to Kibra degradation, whereas decreasing cortical tension increases Kibra abundance. Our study also implicates Par-1 in regulating Kib abundance downstream of cortical tension. We demonstrate that Par-1 promotes ubiquitin-mediated Kib degradation in a Hippo complex-dependent manner and is required for tension-induced Kib degradation. Collectively, our results reveal a previously unknown molecular mechanism by which cortical tension affects Hippo signaling and provide novel insights into the role of mechanical forces in growth control.
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Affiliation(s)
- Sherzod A. Tokamov
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Stephan Buiter
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Anne Ullyot
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Gordana Scepanovic
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering and Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Richard G. Fehon
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
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3
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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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4
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Bonello TT, Cai D, Fletcher GC, Wiengartner K, Pengilly V, Lange KS, Liu Z, Lippincott‐Schwartz J, Kavran JM, Thompson BJ. Phase separation of Hippo signalling complexes. EMBO J 2023; 42:e112863. [PMID: 36807601 PMCID: PMC10015380 DOI: 10.15252/embj.2022112863] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/12/2023] [Accepted: 01/23/2023] [Indexed: 02/22/2023] Open
Abstract
The Hippo pathway was originally discovered to control tissue growth in Drosophila and includes the Hippo kinase (Hpo; MST1/2 in mammals), scaffold protein Salvador (Sav; SAV1 in mammals) and the Warts kinase (Wts; LATS1/2 in mammals). The Hpo kinase is activated by binding to Crumbs-Expanded (Crb-Ex) and/or Merlin-Kibra (Mer-Kib) proteins at the apical domain of epithelial cells. Here we show that activation of Hpo also involves the formation of supramolecular complexes with properties of a biomolecular condensate, including concentration dependence and sensitivity to starvation, macromolecular crowding, or 1,6-hexanediol treatment. Overexpressing Ex or Kib induces formation of micron-scale Hpo condensates in the cytoplasm, rather than at the apical membrane. Several Hippo pathway components contain unstructured low-complexity domains and purified Hpo-Sav complexes undergo phase separation in vitro. Formation of Hpo condensates is conserved in human cells. We propose that apical Hpo kinase activation occurs in phase separated "signalosomes" induced by clustering of upstream pathway components.
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Affiliation(s)
- Teresa T Bonello
- EMBL Australia, John Curtin School of Medical ResearchAustralian National UniversityCanberraACTAustralia
| | - Danfeng Cai
- HHMI Janelia Research CampusAshburnVAUSA
- Department of Biochemistry and Molecular BiologyBloomberg School of Public HealthBaltimoreMDUSA
| | | | - Kyler Wiengartner
- Department of Biochemistry and Molecular BiologyBloomberg School of Public HealthBaltimoreMDUSA
| | - Victoria Pengilly
- EMBL Australia, John Curtin School of Medical ResearchAustralian National UniversityCanberraACTAustralia
| | - Kimberly S Lange
- Department of Biochemistry and Molecular BiologyBloomberg School of Public HealthBaltimoreMDUSA
| | - Zhe Liu
- HHMI Janelia Research CampusAshburnVAUSA
| | | | - Jennifer M Kavran
- Department of Biochemistry and Molecular BiologyBloomberg School of Public HealthBaltimoreMDUSA
- Department of Biophysics and Biophysical Chemistry, and Department of OncologyJohns Hopkins School of MedicineBaltimoreMDUSA
| | - Barry J Thompson
- EMBL Australia, John Curtin School of Medical ResearchAustralian National UniversityCanberraACTAustralia
- Epithelial Biology LaboratoryThe Francis Crick InstituteLondonUK
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5
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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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7
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Functional characterization of FBXL7 as a novel player in human cancers. Cell Death Dis 2022; 8:342. [PMID: 35906197 PMCID: PMC9338262 DOI: 10.1038/s41420-022-01143-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 11/09/2022]
Abstract
F-box and leucine-rich repeat protein 7 (FBXL7), an F-box protein responsible for substrate recognition by the SKP1-Cullin-1-F-box (SCF) ubiquitin ligases, plays an emerging role in the regulation of tumorigenesis and tumor progression. FBXL7 promotes polyubiquitylation and degradation of diverse substrates and is involved in many biological processes, including apoptosis, cell proliferation, cell migration and invasion, tumor metastasis, DNA damage, glucose metabolism, planar cell polarity, and drug resistance. In this review, we summarize the downstream substrates and upstream regulators of FBXL7. We then discuss its role in tumorigenesis and tumor progression as either an oncoprotein or a tumor suppressor, and further describe its aberrant expression and association with patient survival in human cancers. Finally, we provide future perspectives on validating FBXL7 as a cancer biomarker for diagnosis and prognosis and/or as a potential therapeutic target for anticancer treatment.
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8
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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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9
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Zhu H. Elucidate growth control mechanisms using reconstructed spatiotemporal distributions of signaling events. Comput Struct Biotechnol J 2021; 19:3618-3627. [PMID: 34257840 PMCID: PMC8249872 DOI: 10.1016/j.csbj.2021.06.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 05/19/2021] [Accepted: 06/12/2021] [Indexed: 11/30/2022] Open
Abstract
A fundamental biological question is how diverse and complex signaling and patterning is controlled correctly to generate distinct tissues, organs, and body plans, but incorrectly in diseased cells and tissues. Signaling pathways important for growth control have been identified, but to identify the mechanisms their transient and context-dependent interactions encode is more difficult. Currently computational systems biology aims to infer the control mechanisms by investigating quantitative changes of gene expression and protein concentrations, but this inference is difficult in nature. We propose it is desirable to explicitly simulate events and orders of gene regulation and protein interactions, which better elucidate control mechanisms, and report a method and tool with three examples. The Drosophila wing model includes Wnt, PCP, and Hippo pathways and mechanical force, incorporates well-confirmed experimental findings, and generates novel results. The other two examples illustrate the building of three-dimensional and large-scale models. These examples support that reconstructed spatiotemporal distributions of key signaling events help elucidate growth control mechanisms. As biologists pay increasing attention to disordered signaling in diseased cells, to develop new modeling methods and tools for conducting new computational studies is important.
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Affiliation(s)
- Hao Zhu
- Bioinformatics Section, School of Basic Medical Sciences, Southern Medical University, Shatai Road, Guangzhou 510515, China.,Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, China
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10
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Tokamov SA, Su T, Ullyot A, Fehon RG. Negative feedback couples Hippo pathway activation with Kibra degradation independent of Yorkie-mediated transcription. eLife 2021; 10:62326. [PMID: 33555257 PMCID: PMC7895526 DOI: 10.7554/elife.62326] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 02/08/2021] [Indexed: 12/20/2022] Open
Abstract
The Hippo (Hpo) pathway regulates tissue growth in many animals. Multiple upstream components promote Hpo pathway activity, but the organization of these different inputs, the degree of crosstalk between them, and whether they are regulated in a distinct manner is not well understood. Kibra (Kib) activates the Hpo pathway by recruiting the core Hpo kinase cassette to the apical cortex. Here, we show that the Hpo pathway downregulates Drosophila Kib levels independently of Yorkie-mediated transcription. We find that Hpo signaling complex formation promotes Kib degradation via SCFSlimb-mediated ubiquitination, that this effect requires Merlin, Salvador, Hpo, and Warts, and that this mechanism functions independently of other upstream Hpo pathway activators. Moreover, Kib degradation appears patterned by differences in mechanical tension across the wing. We propose that Kib degradation mediated by Hpo pathway components and regulated by cytoskeletal tension serves to control Kib-driven Hpo pathway activation and ensure optimally scaled and patterned tissue growth.
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Affiliation(s)
- Sherzod A Tokamov
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, United States.,Committee on Development, Regeneration and Stem Cell Biology, The University of Chicago, Chicago, United States
| | - Ting Su
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, United States
| | - Anne Ullyot
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, United States
| | - Richard G Fehon
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, United States.,Committee on Development, Regeneration and Stem Cell Biology, The University of Chicago, Chicago, United States
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11
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Kong S, Fang Y, Wang B, Cao Y, He R, Zhao Z. miR-152-5p suppresses glioma progression and tumorigenesis and potentiates temozolomide sensitivity by targeting FBXL7. J Cell Mol Med 2020; 24:4569-4579. [PMID: 32150671 PMCID: PMC7176889 DOI: 10.1111/jcmm.15114] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/13/2020] [Accepted: 02/19/2020] [Indexed: 12/12/2022] Open
Abstract
A generally used chemotherapeutic drug for glioma, a frequently diagnosed brain tumour, is temozolomide (TMZ). Our study investigated the activity of FBXL7 and miR-152-5p in glioma. Levels of microRNA-152-5p (miR-152-5p) and the transcript and protein of FBXL7 were assessed by real-time PCR and Western blotting, respectively. The migratory and invasive properties of cells were measured by Transwell migration and invasion assay and their viability were examined using CCK-8 assay. Further, the putative interaction between FBXL7 and miR-152-5p were analysed bioinformatically and by luciferase assay. The activities of FBXL7, TMZ and miR-152-5p were analysed in vivo singly or in combination, on mouse xenografts, in glioma tumorigenesis. The expression of FBXL7 in glioma tissue is significantly up-regulated, which is related to the poor prognosis and the grade of glioma. TMZ-induced cytotoxicity, proliferation, migration and invasion in glioma cells were impeded by the knock-down of FBXL7 or overexpressed miR-152-5p. Furthermore, the expression of miR-152-5p reduced remarkably in glioma cells and it exerted its activity through targeted FBXL7. Overexpression of miR-152-5p and knock-down of FBXL7 in glioma xenograft models enhanced TMZ-mediated anti-tumour effect and impeded tumour growth. Thus, the miR-152-5p suppressed the progression of glioma and associated tumorigenesis, targeted FBXL7 and increased the effect of TMZ-induced cytotoxicity in glioma cells, further enhancing our knowledge of FBXL7 activity in glioma.
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Affiliation(s)
- Shiqi Kong
- Department of NeurosurgeryThe Second Hospital of Hebei Medical UniversityShijiazhuangHebeiChina
| | - Yanwei Fang
- Department of NeurosurgeryThe Second Hospital of Hebei Medical UniversityShijiazhuangHebeiChina
| | - Bingqian Wang
- Department of NeurosurgeryXingtai People's HospitalXingtaiHebeiChina
| | - Yingxiao Cao
- Department of NeurosurgeryXingtai People's HospitalXingtaiHebeiChina
| | - Runzhi He
- Department of NeurosurgeryXingtai People's HospitalXingtaiHebeiChina
| | - Zongmao Zhao
- Department of NeurosurgeryThe Second Hospital of Hebei Medical UniversityShijiazhuangHebeiChina
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12
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Boone PM, Paterson S, Mohajeri K, Zhu W, Genetti CA, Tai DJC, Nori N, Agrawal PB, Bacino CA, Bi W, Talkowski ME, Hogan BM, Rodan LH. Biallelic mutation of FBXL7 suggests a novel form of Hennekam syndrome. Am J Med Genet A 2019; 182:189-194. [PMID: 31633297 PMCID: PMC10081920 DOI: 10.1002/ajmg.a.61392] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/16/2019] [Accepted: 09/27/2019] [Indexed: 01/25/2023]
Abstract
Hennekam lymphangiectasia-lymphedema syndrome is an autosomal recessive disorder characterized by congenital lymphedema, intestinal lymphangiectasia, facial dysmorphism, and variable intellectual disability. Known disease genes include CCBE1, FAT4, and ADAMTS3. In a patient with clinically diagnosed Hennekam syndrome but without mutations or copy-number changes in the three known disease genes, we identified a homozygous single-exon deletion affecting FBXL7. Specifically, exon 3, which encodes the F-box domain and several leucine-rich repeats of FBXL7, is eliminated. Our analyses of databases representing >100,000 control individuals failed to identify biallelic loss-of-function variants in FBXL7. Published studies in Drosophila indicate Fbxl7 interacts with Fat, of which human FAT4 is an ortholog, and mutation of either gene yields similar morphological consequences. These data suggest that FBXL7 may be the fourth gene for Hennekam syndrome, acting via a shared pathway with FAT4.
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Affiliation(s)
- Philip M Boone
- Harvard Genetics Training Program, Boston, Massachusetts.,Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts.,Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - Scott Paterson
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Kiana Mohajeri
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts.,PhD Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts
| | | | - Casie A Genetti
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts
| | - Derek J C Tai
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - Neeharika Nori
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts
| | - Pankaj B Agrawal
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts.,Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts
| | | | | | - Michael E Talkowski
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.,Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, Massachusetts
| | - Benjamin M Hogan
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Lance H Rodan
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts.,Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
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13
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Lin S, Yu L, Zhang H. Transcriptomic Responses to Thermal Stress and Varied Phosphorus Conditions in Fugacium kawagutii. Microorganisms 2019; 7:microorganisms7040096. [PMID: 30987028 PMCID: PMC6517890 DOI: 10.3390/microorganisms7040096] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/18/2019] [Accepted: 03/30/2019] [Indexed: 01/08/2023] Open
Abstract
Coral reef-associated Symbiodiniaceae live in tropical and oligotrophic environments and are prone to heat and nutrient stress. How their metabolic pathways respond to pulses of warming and phosphorus (P) depletion is underexplored. Here, we conducted RNA-seq analysis to investigate transcriptomic responses to thermal stress, phosphate deprivation, and organic phosphorus (OP) replacement in Fugacium kawagutii. Using dual-algorithm (edgeR and NOIseq) to remedy the problem of no replicates, we conservatively found 357 differentially expressed genes (DEGs) under heat stress, potentially regulating cell wall modulation and the transport of iron, oxygen, and major nutrients. About 396 DEGs were detected under P deprivation and 671 under OP utilization, both mostly up-regulated and potentially involved in photosystem and defensome, despite different KEGG pathway enrichments. Additionally, we identified 221 genes that showed relatively stable expression levels across all conditions (likely core genes), mostly catalytic and binding proteins. This study reveals a wide range of, and in many cases previously unrecognized, molecular mechanisms in F. kawagutii to cope with heat stress and phosphorus-deficiency stress. Their quantitative expression dynamics, however, requires further verification with triplicated experiments, and the data reported here only provide clues for generating testable hypotheses about molecular mechanisms underpinning responses and adaptation in F. kawagutii to temperature and nutrient stresses.
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Affiliation(s)
- Senjie Lin
- Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA.
| | - Liying Yu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, Fujian, China.
| | - Huan Zhang
- Department of Marine Sciences, University of Connecticut, Groton, CT 06340, USA.
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14
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Early girl is a novel component of the Fat signaling pathway. PLoS Genet 2019; 15:e1007955. [PMID: 30699121 PMCID: PMC6370246 DOI: 10.1371/journal.pgen.1007955] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/11/2019] [Accepted: 01/11/2019] [Indexed: 01/05/2023] Open
Abstract
The Drosophila protocadherins Dachsous and Fat regulate growth and tissue polarity by modulating the levels, membrane localization and polarity of the atypical myosin Dachs. Localization to the apical junctional membrane is critical for Dachs function, and the adapter protein Vamana/Dlish and palmitoyl transferase Approximated are required for Dachs membrane localization. However, how Dachs levels are regulated is poorly understood. Here we identify the early girl gene as playing an essential role in Fat signaling by limiting the levels of Dachs protein. early girl mutants display overgrowth of the wings and reduced cross vein spacing, hallmark features of mutations affecting Fat signaling. Genetic experiments reveal that it functions in parallel with Fat to regulate Dachs. early girl encodes an E3 ubiquitin ligase, physically interacts with Dachs, and regulates its protein stability. Concomitant loss of early girl and approximated results in accumulation of Dachs and Vamana in cytoplasmic punctae, suggesting that it also regulates their trafficking to the apical membrane. Our findings establish a crucial role for early girl in Fat signaling, involving regulation of Dachs and Vamana, two key downstream effectors of this pathway. During development, organs grow to achieve a consistent final size. The evolutionarily conserved Hippo signaling network plays a central role in organ size control, and when dysregulated can be associated with cancer and other diseases. Fat signaling is one of several upstream pathways that impinge on Hippo signaling to regulate organ growth. We describe here identification of the Drosophila early girl gene as a new component of the Fat signaling pathway. We show that Early girl controls Fat signaling by regulating the levels of the Dachs protein. However Early girl differs from other Fat signaling regulators in that it doesn’t influence planar cell polarity or control the polarity of Dachs localization. early girl encodes a conserved protein that is predicted to influence protein stability, and it can physically associate with Dachs. We also discovered that Early girl acts together with another protein, called Approximated, to regulate the sub-cellular localization of Dachs and a Dachs-interacting protein called Vamana. Altogether, our observations establish Early girl as an essential component of Fat signaling that acts to regulate the levels and localization of Dachs and Vamana.
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15
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Fat-regulated adaptor protein Dlish binds the growth suppressor Expanded and controls its stability and ubiquitination. Proc Natl Acad Sci U S A 2019; 116:1319-1324. [PMID: 30606799 PMCID: PMC6347691 DOI: 10.1073/pnas.1811891116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
To regulate the growth and size of organs, cells can use information from their neighbors to modify intracellular mediators of cell proliferation. The intracellular Hippo pathway is a widely utilized nexus for growth control in animals, but its regulation by extracellular signals is not fully understood. We here identify a pathway that regulates organ size in Drosophila, triggered by the transmembrane receptor, the giant protocadherin Fat. We show that the Fat-regulated SH3 domain adaptor protein Dlish binds to and reduces the stability of the growth suppressor Expanded, a known regulator of the Hippo pathway. The destabilization of Expanded by Dlish works in parallel to a previously established pathway in which Dlish increases levels of the growth-stimulating protein Dachs. The Drosophila protocadherin Fat controls organ size through the Hippo pathway, but the biochemical links to the Hippo pathway components are still poorly defined. We previously identified Dlish, an SH3 domain protein that physically interacts with Fat and the type XX myosin Dachs, and showed that Fat’s regulation of Dlish levels and activity helps limit Dachs-mediated inhibition of Hippo pathway activity. We here characterize a parallel growth control pathway downstream of Fat and Dlish. Using immunoprecipitation and mass spectrometry to search for Dlish partners, we find that Dlish binds the FERM domain growth repressor Expanded (Ex); Dlish SH3 domains directly bind sites in the Ex C terminus. We further show that, in vivo, Dlish reduces the subapical accumulation of Ex, and that loss of Dlish blocks the destabilization of Ex caused by loss of Fat. Moreover, Dlish can bind the F-box E3 ubiquitin ligase Slimb and promote Slimb-mediated ubiquitination of Expanded in vitro. Both the in vitro and in vivo effects of Dlish on Ex require Slimb, strongly suggesting that Dlish destabilizes Ex by helping recruit Slimb-containing E3 ubiquitin ligase complexes to Ex.
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16
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FBXL7 Upregulation Predicts a Poor Prognosis and Associates with a Possible Mechanism for Paclitaxel Resistance in Ovarian Cancer. J Clin Med 2018; 7:jcm7100330. [PMID: 30301218 PMCID: PMC6209951 DOI: 10.3390/jcm7100330] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/25/2018] [Accepted: 10/03/2018] [Indexed: 01/01/2023] Open
Abstract
Paclitaxel (PTX) is a common regimen used to treat patients with ovarian cancer. Although approximately 60% of ovarian cancer patients exhibit a pathologic complete response (pCR), approximately 40% of patients appear to be insensitive to PTX adjuvant therapy. Thus, identifying a useful biomarker to predict pCR would be of great help to ovarian cancer patients who decide to receive PTX treatment. We found that FBXL7 was downregulated in OVSAHO (PTX-sensitive) but upregulated in KURAMOCHI (PTX-resistant) cells after PTX treatment at cytotoxic concentrations. Moreover, our data showed that the fold change of FBXL7 expression post-treatment with PTX was causally correlated with the 50% inhibitory concentrations (IC50) of PTX in a panel of ovarian cancer cell lines. In assessments of progression-free survival probability, high levels of FBXL7 transcript strongly predicted a poor prognosis and unfavorable response to PTX-based chemotherapy in patients with ovarian cancer. The knockdown of FBXL7 predominantly enhanced the cytotoxic effectiveness of PTX on the PTX-resistant KURAMOCHI cells. FBXL7 may be a useful biomarker for predicting complete pathologic response in ovarian cancer patients who decide to receive post-operative PTX therapy.
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17
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Gou J, Lin L, Othmer HG. A Model for the Hippo Pathway in the Drosophila Wing Disc. Biophys J 2018; 115:737-747. [PMID: 30041810 PMCID: PMC6103738 DOI: 10.1016/j.bpj.2018.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 06/21/2018] [Accepted: 07/02/2018] [Indexed: 01/18/2023] Open
Abstract
Although significant progress has been made toward understanding morphogen-mediated patterning in development, control of the size and shape of tissues via local and global signaling is poorly understood. In particular, little is known about how cell-cell interactions are involved in the control of tissue size. The Hippo pathway in the Drosophila wing disc involves cell-cell interactions via cadherins, which lead to modulation of Yorkie, a cotranscriptional factor that affects control of the cell cycle and growth, and studies involving over- and underexpression of components of this pathway reveal conditions that lead to tissue over- or undergrowth. Here, we develop a mathematical model of the Hippo pathway that can qualitatively explain these observations, made in both whole-disc mutants and mutant-clone experiments. We find that a number of nonintuitive experimental results can be explained by subtle changes in the balances between inputs to the Hippo pathway and suggest some predictions that can be tested experimentally. We also show that certain components of the pathway are polarized at the single-cell level, which replicates observations of planar cell polarity. Because the signal transduction and growth control pathways are highly conserved between Drosophila and mammalian systems, the model we formulate can be used as a framework to guide future experimental work on the Hippo pathway in both Drosophila and mammalian systems.
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Affiliation(s)
- Jia Gou
- School of Mathematics, University of Minnesota, Minneapolis, Minnesota
| | - Lin Lin
- School of Mathematics, University of Minnesota, Minneapolis, Minnesota
| | - Hans G Othmer
- School of Mathematics, University of Minnesota, Minneapolis, Minnesota.
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18
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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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19
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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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20
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Elbediwy A, Thompson BJ. Evolution of mechanotransduction via YAP/TAZ in animal epithelia. Curr Opin Cell Biol 2018; 51:117-123. [PMID: 29477107 DOI: 10.1016/j.ceb.2018.02.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 10/18/2022]
Abstract
Mechanical stretch forces can control the growth of epithelial tissues such as mammalian skin, whose surface area is precisely coordinated with body size. In skin keratinocytes cultured in vitro, mechanical forces acting via Integrin adhesions and the actin cytoskeleton have been shown to induce nuclear translocation of YAP/TAZ co-activators to induce cell proliferation. Furthermore, conditional knockouts of both YAP (also called YAP1) and TAZ (also called WWTR1) in mouse skin resemble the phenotype of skin-specific loss of Integrin beta1 (ITGB1), indicating that this signalling mechanism is important in vivo. Curiously, Integrins are dispensable in Drosophila to activate the sole YAP/TAZ homolog Yorkie (Yki), which has lost the C-terminal PDZ-binding motif needed to promote nuclear localization of YAP/TAZ in mammalian cells. Differences in the structure of the epidermis between deuterostomes (e.g.: stratified squamous skin of mammals) and protostomes (e.g.: monolayered columnar epidermis of Drosophila) may explain this evolutionary divergence. Monolayered columnar epithelia feature a well-differentiated apical membrane domain, where proteins such as Crumbs, Expanded, Merlin and Kibra activate the Hippo pathway to repress Drosophila Yki. Stratified squamous epithelia lack an apical domain and thus depend primarily on basal Integrin adhesions to activate YAP/TAZ in basal layer stem cells via multiple postulated signalling mechanisms. Finally, YAP and TAZ retain the ability to sense the apical domain in the columnar epithelial cells lining internal organs such as the lung bronchus, where YAP/TAZ localize to the nucleus in proliferating basal layer stem cells but translocate to the cytoplasm in differentiated columnar cells.
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Affiliation(s)
- Ahmed Elbediwy
- Epithelial Biology Laboratory, The Francis Crick Institute, 1 Midland Rd, London NW1 1AT, United Kingdom
| | - Barry J Thompson
- Epithelial Biology Laboratory, The Francis Crick Institute, 1 Midland Rd, London NW1 1AT, United Kingdom.
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21
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Configuring a robust nervous system with Fat cadherins. Semin Cell Dev Biol 2017; 69:91-101. [PMID: 28603077 DOI: 10.1016/j.semcdb.2017.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/26/2017] [Accepted: 06/07/2017] [Indexed: 01/14/2023]
Abstract
Atypical Fat cadherins represent a small but versatile group of signaling molecules that influence proliferation and tissue polarity. With huge extracellular domains and intracellular domains harboring many independent protein interaction sites, Fat cadherins are poised to translate local cell adhesion events into a variety of cell behaviors. The need for such global coordination is particularly prominent in the nervous system, where millions of morphologically diverse neurons are organized into functional networks. As we learn more about their biological functions and molecular properties, increasing evidence suggests that Fat cadherins mediate contact-induced changes that ultimately impose a structure to developing neuronal circuits.
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22
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Tissue growth and tumorigenesis in Drosophila: cell polarity and the Hippo pathway. Curr Opin Cell Biol 2017; 48:1-9. [PMID: 28364663 DOI: 10.1016/j.ceb.2017.03.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 03/07/2017] [Accepted: 03/10/2017] [Indexed: 12/17/2022]
Abstract
Cell polarity regulation is critical for defining membrane domains required for the establishment and maintenance of the apical-basal axis in epithelial cells (apico-basal polarity), asymmetric cell divisions, planar organization of tissues (planar cell polarity), and the formation of the front-rear axis in cell migration (front-rear polarity). In the vinegar fly, Drosophila melanogaster, cell polarity regulators also interact with the Hippo tissue growth control signaling pathway. In this review we survey the recent Drosophila literature linking cell polarity regulators with the Hippo pathway in epithelial tissue growth, neural stem cell asymmetric divisions and in cell migration in physiological and tumorigenic settings.
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23
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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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24
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Kale A, Rimesso G, Baker NE. Local Cell Death Changes the Orientation of Cell Division in the Developing Drosophila Wing Imaginal Disc Without Using Fat or Dachsous as Orienting Signals. PLoS One 2016; 11:e0167637. [PMID: 28030539 PMCID: PMC5193341 DOI: 10.1371/journal.pone.0167637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/17/2016] [Indexed: 12/21/2022] Open
Abstract
Drosophila imaginal disc cells exhibit preferred cell division orientations according to location within the disc. These orientations are altered if cell death occurs within the epithelium, such as is caused by cell competition or by genotypes affecting cell survival. Both normal cell division orientations, and their orientations after cell death, depend on the Fat-Dachsous pathway of planar cell polarity (PCP). The hypothesis that cell death initiates a planar polarity signal was investigated. When clones homozygous for the pineapple eye (pie) mutation were made to initiate cell death, neither Dachsous nor Fat was required in pie cells for the re-orientation of nearby cells, indicating a distinct signal for this PCP pathway. Dpp and Wg were also not needed for pie clones to re-orient cell division. Cell shapes were evaluated in wild type and mosaic wing discs to assess mechanical consequences of cell loss. Although proximal wing disc cells and cells close to the dorso-ventral boundary were elongated in their preferred cell division axes in wild type discs, cell shapes in much of the wing pouch were symmetrical on average and did not predict their preferred division axis. Cells in pie mutant clones were slightly larger than their normal counterparts, consistent with mechanical stretching following cell loss, but no bias in cell shape was detected in the surrounding cells. These findings indicate that an unidentified signal influences PCP-dependent cell division orientation in imaginal discs.
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Affiliation(s)
- Abhijit Kale
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NYC, NY, United States of America
| | - Gerard Rimesso
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NYC, NY, United States of America
| | - Nicholas E. Baker
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NYC, NY, United States of America
- Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NYC, NY, United States of America
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NYC, NY, United States of America
- * E-mail:
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25
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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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26
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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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27
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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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28
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Elbediwy A, Vincent-Mistiaen ZI, Thompson BJ. YAP and TAZ in epithelial stem cells: A sensor for cell polarity, mechanical forces and tissue damage. Bioessays 2016; 38:644-53. [PMID: 27173018 PMCID: PMC5031209 DOI: 10.1002/bies.201600037] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The YAP/TAZ family of transcriptional co‐activators drives cell proliferation in epithelial tissues and cancers. Yet, how YAP and TAZ are physiologically regulated remains unclear. Here we review recent reports that YAP and TAZ act primarily as sensors of epithelial cell polarity, being inhibited when cells differentiate an apical membrane domain, and being activated when cells contact the extracellular matrix via their basal membrane domain. Apical signalling occurs via the canonical Crumbs/CRB‐Hippo/MST‐Warts/LATS kinase cascade to phosphorylate and inhibit YAP/TAZ. Basal signalling occurs via Integrins and Src family kinases to phosphorylate and activate YAP/TAZ. Thus, YAP/TAZ is localised to the nucleus in basal stem/progenitor cells and cytoplasm in differentiated squamous cells or columnar cells. In addition, other signals such as mechanical forces, tissue damage and possibly receptor tyrosine kinases (RTKs) can influence MST‐LATS or Src family kinase activity to modulate YAP/TAZ activity.
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Affiliation(s)
- Ahmed Elbediwy
- Epithelial Biology Laboratory, Francis Crick Institute, London, UK
| | | | - Barry J Thompson
- Epithelial Biology Laboratory, Francis Crick Institute, London, UK
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29
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Bosveld F, Guirao B, Wang Z, Rivière M, Bonnet I, Graner F, Bellaïche Y. Modulation of junction tension by tumor-suppressors and proto-oncogenes regulates cell-cell contacts. Development 2016; 143:623-34. [DOI: 10.1242/dev.127993] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 01/07/2016] [Indexed: 12/26/2022]
Abstract
Tumor-suppressor and proto-oncogenes play critical roles in tissue proliferation. Furthermore, deregulation of their functions is deleterious to tissue architecture and can result in the sorting of somatic rounded clones minimizing their contact with surrounding wild-type (wt) cells. Defects in somatic clones shape correlate with defects in proliferation, cell affinity, cell-cell adhesion, oriented cell division and cortical elasticity. Combining genetics, live-imaging, laser ablation and computer simulations, we aim to analyze whether distinct or similar mechanisms can account for the common role of tumor-suppressor and proto-oncogenes in cell-cell contact regulation. In Drosophila epithelia, Fat (Ft) and Dachsous (Ds) tumor-suppressors regulate cell proliferation, tissue morphogenesis, planar cell polarity and junction tension. By analyzing the time evolution of ft mutant cells and clones, we show that ft clones reduce their cell-cell contact with surrounding wt tissue in the absence of concomitant cell divisions and over-proliferation. This contact reduction depends on opposite changes of junction tensions in the clone bulk and its boundary with neighboring wt tissue. More generally, either clone bulk or boundary junction tensions is modulated by the activation of Yorkie, Myc and Ras yielding similar contact reductions with wt cells. Together our data highlight mechanical roles for proto-oncogene and tumor-suppressor pathways in cell-cell interactions.
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Affiliation(s)
- Floris Bosveld
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | - Boris Guirao
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | - Zhimin Wang
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | - Mathieu Rivière
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
- Present address: Matière et Systèmes Complexes, Université Paris Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France
| | - Isabelle Bonnet
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
- Present address: Laboratoire Physico-Chimie Curie, Institut Curie, CNRS UMR 168, Université Pierre et Marie Curie, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | - François Graner
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
- Present address: Matière et Systèmes Complexes, Université Paris Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France
| | - Yohanns Bellaïche
- Polarity, Division and Morphogenesis Team, Institut Curie, CNRS UMR 3215, INSERM U934, 26 rue d'Ulm, 75248 Paris Cedex 05, France
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30
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Collu GM, Mlodzik M. Planar polarity: converting a morphogen gradient into cellular polarity. Curr Biol 2015; 25:R372-4. [PMID: 25942551 DOI: 10.1016/j.cub.2015.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Epithelial cells are polarized within the apico-basal and planar axes. The latter - planar cell polarity - requires long-range regulation of orientation as well as short-range, cell-to-cell realignment through feedback loops. New insights into the long-range, gradient-type regulation reveal how a kinase translates the morphogen gradient input into cellular orientation.
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Affiliation(s)
- Giovanna M Collu
- Department of Developmental & Regenerative Biology, and Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Marek Mlodzik
- Department of Developmental & Regenerative Biology, and Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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Tosto G, Fu H, Vardarajan BN, Lee JH, Cheng R, Reyes-Dumeyer D, Lantigua R, Medrano M, Jimenez-Velazquez IZ, Elkind MSV, Wright CB, Sacco RL, Pericak-Vance M, Farrer L, Rogaeva E, St George-Hyslop P, Reitz C, Mayeux R. F-box/LRR-repeat protein 7 is genetically associated with Alzheimer's disease. Ann Clin Transl Neurol 2015; 2:810-20. [PMID: 26339675 PMCID: PMC4554442 DOI: 10.1002/acn3.223] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/05/2015] [Accepted: 05/14/2015] [Indexed: 01/28/2023] Open
Abstract
Objective In the context of late-onset Alzheimer’s disease (LOAD) over 20 genes have been identified but, aside APOE, all show small effect sizes, leaving a large part of the genetic component unexplained. Admixed populations, such as Caribbean Hispanics, can provide a valuable contribution because of their unique genetic profile and higher incidence of the disease. We aimed to identify novel loci associated with LOAD. Methods About 4514 unrelated Caribbean Hispanics (2451 cases and 2063 controls) were selected for genome-wide association analysis. Significant loci were further tested in the expanded cohort that also included related family members (n = 5300). Two AD-like transgenic mice models (J20 and rTg4510) were used to study gene expression. Independent data sets of non-Hispanic Whites and African Americans were used to further validate findings, along with publicly available brain expression data sets. Results A novel locus, rs75002042 in FBXL7 (5p15.1), was found genome-wide significant in the case–control cohort (odd ratio [OR] = 0.61, P = 6.19E-09) and confirmed in the related members cohorts (OR = 0.63, P = 4.7E-08). Fbxl7 protein was overexpressed in both AD-like transgenic mice compared to wild-type littermates. Publicly available microarray studies also showed significant overexpression of Fbxl7 in LOAD brains compared to nondemented controls. single-nucleotide polymorphism (SNP) rs75002042 was in complete linkage disequilibrium with other variants in two independent non-Hispanic White and African American data sets (0.0005 < P < 0.02) used for replication. Interpretation FBXL7, encodes a subcellular protein involved in phosphorylation-dependent ubiquitination processes and displays proapoptotic activity. F-box proteins also modulate inflammation and innate immunity, which may be important in LOAD pathogenesis. Further investigations are needed to validate and understand its role in this and other populations.
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Affiliation(s)
- Giuseppe Tosto
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York
| | - Hongjun Fu
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York
| | - Badri N Vardarajan
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York
| | - Joseph H Lee
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York
| | - Rong Cheng
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York
| | - Dolly Reyes-Dumeyer
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York
| | - Rafael Lantigua
- Department of Medicine College of Physicians and Surgeons, School of Public Health, Columbia University New York, New York
| | - Martin Medrano
- School of Medicine, Pontificia Universidad Catolica Madre y Maestra Santiago, Dominican Republic
| | - Ivonne Z Jimenez-Velazquez
- Department of Medicine, Geriatrics Program, School of Medicine, University of Puerto Rico San Juan, Puerto Rico
| | - Mitchell S V Elkind
- The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York ; Department of Neurology, Columbia University New York, New York
| | - Clinton B Wright
- Evelyn F. McKnight Brain Institute and Departments of Neurology, Public Health Sciences, John T. McDonald Department of Human Genetics, University of Miami Miami, Florida, 33136
| | - Ralph L Sacco
- Evelyn F. McKnight Brain Institute and Departments of Neurology, Public Health Sciences, John T. McDonald Department of Human Genetics, University of Miami Miami, Florida, 33136 ; Neuroscience Program, Leonard M. Miller School of Medicine, University of Miami Miami, Florida, 33136
| | - Margaret Pericak-Vance
- Neuroscience Program, Leonard M. Miller School of Medicine, University of Miami Miami, Florida, 33136 ; The John P. Hussman Institute for Human Genomics, University of Miami Miami, Florida, 33136
| | - Lindsay Farrer
- Departments of Medicine (Biomedical Genetics), Neurology, Ophthalmology, Biostatistics and Epidemiology, Boston University Schools of Medicine and Public Health Boston, Massachusetts
| | - Ekaterina Rogaeva
- Tanz Centre for Research in Neurodegenerative Diseases, and Department of Medicine, University of Toronto Krembil Discovery Tower, 60 Leonard Avenue, Toronto, Ontario, Canada, M5T 2S8
| | - Peter St George-Hyslop
- Tanz Centre for Research in Neurodegenerative Diseases, and Department of Medicine, University of Toronto Krembil Discovery Tower, 60 Leonard Avenue, Toronto, Ontario, Canada, M5T 2S8 ; Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge Cambridge, CB2 0XY, United Kingdom
| | - Christiane Reitz
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York ; Department of Neurology, Columbia University New York, New York
| | - Richard Mayeux
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, School of Public Health, Columbia University New York, New York ; The Gertrude H. Sergievsky Center, School of Public Health, Columbia University New York, New York ; Department of Neurology, Columbia University New York, New York ; Department of Psychiatry, School of Public Health, Columbia University New York, New York ; Department of Epidemiology, School of Public Health, Columbia University New York, New York
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Control of organ growth by patterning and hippo signaling in Drosophila. Cold Spring Harb Perspect Biol 2015; 7:7/6/a019224. [PMID: 26032720 DOI: 10.1101/cshperspect.a019224] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Control of organ size is of fundamental importance and is controlled by genetic, environmental, and mechanical factors. Studies in many species have pointed to the existence of both organ-extrinsic and -intrinsic size-control mechanisms, which ultimately must coordinate to regulate organ size. Here, we discuss organ size control by organ patterning and the Hippo pathway, which both act in an organ-intrinsic fashion. The influence of morphogens and other patterning molecules couples growth and patterning, whereas emerging evidence suggests that the Hippo pathway controls growth in response to mechanical stimuli and signals emanating from cell-cell interactions. Several points of cross talk have been reported between signaling pathways that control organ patterning and the Hippo pathway, both at the level of membrane receptors and transcriptional regulators. However, despite substantial progress in the past decade, key questions in the growth-control field remain, including precisely how and when organ patterning and the Hippo pathway communicate to control size, and whether these communication mechanisms are organ specific or general. In addition, elucidating mechanisms by which organ-intrinsic cues, such as patterning factors and the Hippo pathway, interface with extrinsic cues, such as hormones to control organ size, remain unresolved.
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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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