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Long-Range and Directional Allostery of Actin Filaments Plays Important Roles in Various Cellular Activities. Int J Mol Sci 2020; 21:ijms21093209. [PMID: 32370032 PMCID: PMC7246755 DOI: 10.3390/ijms21093209] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/27/2020] [Accepted: 04/30/2020] [Indexed: 12/18/2022] Open
Abstract
A wide variety of uniquely localized actin-binding proteins (ABPs) are involved in various cellular activities, such as cytokinesis, migration, adhesion, morphogenesis, and intracellular transport. In a micrometer-scale space such as the inside of cells, protein molecules diffuse throughout the cell interior within seconds. In this condition, how can ABPs selectively bind to particular actin filaments when there is an abundance of actin filaments in the cytoplasm? In recent years, several ABPs have been reported to induce cooperative conformational changes to actin filaments allowing structural changes to propagate along the filament cables uni- or bidirectionally, thereby regulating the subsequent binding of ABPs. Such propagation of ABP-induced cooperative conformational changes in actin filaments may be advantageous for the elaborate regulation of cellular activities driven by actin-based machineries in the intracellular space, which is dominated by diffusion. In this review, we focus on long-range allosteric regulation driven by cooperative conformational changes of actin filaments that are evoked by binding of ABPs, and discuss roles of allostery of actin filaments in narrow intracellular spaces.
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Zuidscherwoude M, Green HLH, Thomas SG. Formin proteins in megakaryocytes and platelets: regulation of actin and microtubule dynamics. Platelets 2018; 30:23-30. [PMID: 29913076 PMCID: PMC6406210 DOI: 10.1080/09537104.2018.1481937] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The platelet and megakaryocyte cytoskeletons are essential for formation and function of these cells. A dynamic, properly organised tubulin and actin cytoskeleton is critical for the development of the megakaryocyte and the extension of proplatelets. Tubulin in particular plays a pivotal role in the extension of these proplatelets and the release of platelets from them. Tubulin is further required for the maintenance of platelet size, and actin is the driving force for shape change, spreading and platelet contraction during platelet activation. Whilst several key proteins which regulate these cytoskeletons have been described in detail, the formin family of proteins has received less attention. Formins are intriguing as, although they were initially believed to simply be a nucleator of actin polymerisation, increasing evidence shows they are important regulators of the crosstalk between the actin and microtubule cytoskeletons. In this review, we will introduce the formin proteins and consider the recent evidence that they play an important role in platelets and megakaryocytes in mediating both the actin and tubulin cytoskeletons.
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Affiliation(s)
- Malou Zuidscherwoude
- a Institute of Cardiovascular Sciences , University of Birmingham , Birmingham , UK.,b Centre of Membrane Proteins and Receptors (COMPARE) , University of Birmingham and University of Nottingham , Midlands , UK
| | - Hannah L H Green
- a Institute of Cardiovascular Sciences , University of Birmingham , Birmingham , UK
| | - Steven G Thomas
- a Institute of Cardiovascular Sciences , University of Birmingham , Birmingham , UK.,b Centre of Membrane Proteins and Receptors (COMPARE) , University of Birmingham and University of Nottingham , Midlands , UK
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3
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New nuclear and perinuclear functions of formins. Biochem Soc Trans 2017; 44:1701-1708. [PMID: 27913680 DOI: 10.1042/bst20160187] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/29/2016] [Accepted: 09/02/2016] [Indexed: 12/12/2022]
Abstract
Formin family proteins (formins) represent an evolutionary conserved protein family encoded in the genome of a wide range of eukaryotes. Formins are hallmarked by a formin homology 1 (FH1) domain juxtaposed to an FH2 domain whereby they control actin and microtubule dynamics. Not surprisingly, formins are best known as key regulators of the cytoskeleton in a variety of morphogenetic processes. However, mounting evidence implicates several formins in the assembly and organization of actin within and around the nucleus. In addition, actin-independent roles for formins have recently been discovered. In this mini-review, we summarize these findings and highlight the novel nuclear and perinulcear functions of formins. In light of the emerging new biology of formins, we also discuss the fundamental principles governing the versatile activity and multimodal regulation of these proteins.
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Reber I, Keller I, Becker D, Flury C, Welle M, Drögemüller C. Wattles in goats are associated with the FMN1/GREM1 region on chromosome 10. Anim Genet 2015; 46:316-20. [PMID: 25736034 PMCID: PMC5024000 DOI: 10.1111/age.12279] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/23/2015] [Indexed: 01/29/2023]
Abstract
The presence of congenital appendages (wattles) on the throat of goats is supposed to be under genetic control with a dominant mode of inheritance. Wattles contain a cartilaginous core covered with normal skin resembling early stages of extremities. To map the dominant caprine wattles (W) locus, we collected samples of 174 goats with wattles and 167 goats without wattles from nine different Swiss goat breeds. The samples were genotyped with the 53k goat SNP chip for a subsequent genome-wide association study. We obtained a single strong association signal on chromosome 10 in a region containing functional candidate genes for limb development and outgrowth. We sequenced the whole genomes of an informative family trio containing an offspring without wattles and its heterozygous parents with wattles. In the associated goat chromosome 10 region, a total of 1055 SNPs and short indels perfectly co-segregate with the W allele. None of the variants were perfectly associated with the phenotype after analyzing the genome sequences of eight additional goats. We speculate that the causative mutation is located in one of the numerous gaps in the current version of the goat reference sequence and/or represents a larger structural variant which influences the expression of the FMN1 and/or GREM1 genes. Also, we cannot rule out possible genetic or allelic heterogeneity. Our genetic findings support earlier assumptions that wattles are rudimentary developed extremities.
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Affiliation(s)
- I Reber
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland; DermFocus, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3001, Bern, Switzerland
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5
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Sattlegger E, Chernova TA, Gogoi NM, Pillai IV, Chernoff YO, Munn AL. Yeast studies reveal moonlighting functions of the ancient actin cytoskeleton. IUBMB Life 2014; 66:538-45. [PMID: 25138357 DOI: 10.1002/iub.1294] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 07/21/2014] [Indexed: 11/12/2022]
Abstract
Classic functions of the actin cytoskeleton include control of cell size and shape and the internal organization of cells. These functions are manifest in cellular processes of fundamental importance throughout biology such as the generation of cell polarity, cell migration, cell adhesion, and cell division. However, studies in the unicellular model eukaryote Saccharomyces cerevisiae (Baker's yeast) are giving insights into other functions in which the actin cytoskeleton plays a critical role. These include endocytosis, control of protein translation, and determination of protein 3-dimensional shape (especially conversion of normal cellular proteins into prions). Here, we present a concise overview of these new "moonlighting" roles for the actin cytoskeleton and how some of these roles might lie at the heart of important molecular switches. This is an exciting time for researchers interested in the actin cytoskeleton. We show here how studies of actin are leading us into many new and exciting realms at the interface of genetics, biochemistry, and cell biology. While many of the pioneering studies have been conducted using yeast, the conservation of the actin cytoskeleton and its component proteins throughout eukaryotes suggests that these new roles for the actin cytoskeleton may not be restricted to yeast cells but rather may reflect new roles for the actin cytoskeleton of all eukaryotes.
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Affiliation(s)
- Evelyn Sattlegger
- Institute of Natural and Mathematical Sciences, Massey University, Albany, New Zealand
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Affiliation(s)
- Dennis Breitsprecher
- Rosenstiel Basic Medical Sciences Research Center, Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02454, USA
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7
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Simon-Areces J, Dopazo A, Dettenhofer M, Rodriguez-Tebar A, Garcia-Segura LM, Arevalo MA. Formin1 mediates the induction of dendritogenesis and synaptogenesis by neurogenin3 in mouse hippocampal neurons. PLoS One 2011; 6:e21825. [PMID: 21818269 PMCID: PMC3139584 DOI: 10.1371/journal.pone.0021825] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 06/13/2011] [Indexed: 11/21/2022] Open
Abstract
Neurogenin3, a proneural transcription factor controlled by Notch receptor, has been recently shown to regulate dendritogenesis and synaptogenesis in mouse hippocampal neurons. However, little is known about the molecular mechanisms involved in these actions of Ngn3. We have used a microarray analysis to identify Ngn3 regulated genes related with cytoskeleton dynamics. One of such genes is Fmn1, whose protein, Formin1, is associated with actin and microtubule cytoskeleton. Overexpression of the Fmn1 isoform-Ib in cultured mouse hippocampal neurons induced an increase in the number of primary dendrites and in the number of glutamatergic synaptic inputs at 4 days in vitro. The same changes were provoked by overexpression of Ngn3. In addition downregulation of Fmn1 by the use of Fmn1-siRNAs impaired such morphological and synaptic changes induced by Ngn3 overexpression in neurons. These results reveal a previously unknown involvement of Formin1 in dendritogenesis and synaptogenesis and indicate that this protein is a key component of the Ngn3 signaling pathway that controls neuronal differentiation.
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Affiliation(s)
- Julia Simon-Areces
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Ana Dopazo
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Markus Dettenhofer
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alfredo Rodriguez-Tebar
- Centro Andaluz de Biología Molecular y Medicina Regenerativa/Consejo Superior de Investigaciones Cientificas (CABIMER/CSIC), Seville, Spain
| | - Luis Miguel Garcia-Segura
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Maria-Angeles Arevalo
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
- * E-mail:
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Liu R, Linardopoulou EV, Osborn GE, Parkhurst SM. Formins in development: orchestrating body plan origami. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1803:207-25. [PMID: 18996154 PMCID: PMC2838992 DOI: 10.1016/j.bbamcr.2008.09.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Revised: 08/21/2008] [Accepted: 09/26/2008] [Indexed: 01/21/2023]
Abstract
Formins, proteins defined by the presence of an FH2 domain and their ability to nucleate linear F-actin de novo, play a key role in the regulation of the cytoskeleton. Initially thought to primarily regulate actin, recent studies have highlighted a role for formins in the regulation of microtubule dynamics, and most recently have uncovered the ability of some formins to coordinate the organization of both the microtubule and actin cytoskeletons. While biochemical analyses of this family of proteins have yielded many insights into how formins regulate diverse cytoskeletal reorganizations, we are only beginning to appreciate how and when these functional properties are relevant to biological processes in a developmental or organismal context. Developmental genetic studies in fungi, Dictyostelium, vertebrates, plants and other model organisms have revealed conserved roles for formins in cell polarity, actin cable assembly and cytokinesis. However, roles have also been discovered for formins that are specific to particular organisms. Thus, formins perform both global and specific functions, with some of these roles concurring with previous biochemical data and others exposing new properties of formins. While not all family members have been examined across all organisms, the analyses to date highlight the significance of the flexibility within the formin family to regulate a broad spectrum of diverse cytoskeletal processes during development.
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Affiliation(s)
- Raymond Liu
- Division of Basic Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Avenue North Seattle, WA 98109 USA
| | - Elena V. Linardopoulou
- Division of Basic Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Avenue North Seattle, WA 98109 USA
| | - Gregory E. Osborn
- Division of Basic Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Avenue North Seattle, WA 98109 USA
| | - Susan M. Parkhurst
- Division of Basic Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Avenue North Seattle, WA 98109 USA
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Schönichen A, Geyer M. Fifteen formins for an actin filament: a molecular view on the regulation of human formins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1803:152-63. [PMID: 20102729 DOI: 10.1016/j.bbamcr.2010.01.014] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Revised: 12/24/2009] [Accepted: 01/11/2010] [Indexed: 10/19/2022]
Abstract
The regulation of the actin cytoskeleton is a key process for the stability and motility of eukaryotic cells. Besides the Arp2/3 complex and its nucleation promoting factors, WH2 domain-containing proteins and a diverse family of formin proteins have recently been recognized as actin nucleators and potent polymerization factors of actin filaments. Formins are defined by the presence of a catalytic formin homology 2 (FH2) domain, yet, the modular domain architecture appears significantly different for the eight formin families identified in humans. A diverse picture of protein localization, interaction partners and cell specific regulation emerged, suggesting various functions of formins in the building and maintenance of actin filaments. This review focuses on the domain architecture of human formins, the regulation mechanisms of their activation and the diversity in formin cellular functions.
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Affiliation(s)
- André Schönichen
- Max-Planck-Institut für Molekulare Physiologie, Abteilung Physikalische Biochemie, Otto-Hahn-Str. 11, 44227 Dortmund, Germany
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DeWard AD, Eisenmann KM, Matheson SF, Alberts AS. The role of formins in human disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1803:226-33. [PMID: 19941910 DOI: 10.1016/j.bbamcr.2009.11.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 11/06/2009] [Accepted: 11/10/2009] [Indexed: 02/02/2023]
Abstract
Formins are a conserved family of proteins that play key roles in cytoskeletal remodeling. They nucleate and processively elongate non-branched actin filaments and also modulate microtubule dynamics. Despite their significant contributions to cell biology and development, few studies have directly implicated formins in disease pathogenesis. This review highlights the roles of formins in cell division, migration, immunity, and microvesicle formation in the context of human disease. In addition, we discuss the importance of controlling formin activity and protein expression to maintain cell homeostasis.
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Affiliation(s)
- Aaron D DeWard
- Laboratory of Cell Structure and Signal Integration, Van Andel Research Institute, Grand Rapids, MI 49503, USA
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11
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Aspenström P. Formin-binding proteins: modulators of formin-dependent actin polymerization. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1803:174-82. [PMID: 19589360 DOI: 10.1016/j.bbamcr.2009.06.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 06/22/2009] [Accepted: 06/26/2009] [Indexed: 12/27/2022]
Abstract
Formins represent a major branch of actin nucleators along with the Arp2/3 complex, Spire and Cordon-bleu. Formin-mediated actin nucleation requires the formin homology 2 domain and, although the nucleation per se does not require additional factors, formin-binding proteins have been shown to be essential for the regulation of formin-dependent actin assembly in vivo. This regulation could be accomplished by formin-binding proteins being directly involved in formin-driven actin nucleation, by formin-binding proteins influencing the activated state of the formins, by linking formin-driven actin polymerization to Arp2/3 driven actin polymerization, or by influencing the subcellular localization of the formins. This review article will focus on mammalian formin-binding proteins and their roles during vital cellular processes, such as cell migration, cell division and intracellular trafficking.
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Affiliation(s)
- Pontus Aspenström
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Box 280, Nobels väg 16, SE-171 77 Stockholm, Sweden.
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12
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Zhou F, Leder P, Zuniga A, Dettenhofer M. Formin1 disruption confers oligodactylism and alters Bmp signaling. Hum Mol Genet 2009; 18:2472-82. [PMID: 19383632 DOI: 10.1093/hmg/ddp185] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Proper limb development requires concerted communication between cells within the developing limb bud. Several molecules have been identified which contribute to the formation of a circuitry loop consisting in large part of secreted proteins. The intracellular actin nucleator, Formin 1 (Fmn1), has previously been implicated in limb development, but questions remain after the identification of a Gremlin transcriptional enhancer within the 3' end of the Fmn 1 locus. To resolve this issue, a knockout mouse devoid of Fmn1 protein was created and characterized. The mice exhibit a reduction of digit number to four, a deformed posterior metatarsal, phalangeal soft tissue fusion as well as the absence of a fibula to 100% penetrance in the FVB genetic background. Importantly, this mutant allele does not genetically disrupt the characterized Gremlin enhancer, and indeed Gremlin RNA expression is upregulated at the 35 somite stage of development. Our data reveal increased Bone Morphogenetic Protein (Bmp) activity in mice which carry a disruption in Fmn1, as evidenced by upregulation of Msx1 and a decrease in Fgf4 within the apical ectodermal ridge. Additionally, these studies show enhanced activity downstream of the Bmp receptor in cells where Fmn1 is perturbed, suggesting a role for Fmn1 in repression of Bmp signaling.
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Affiliation(s)
- Fen Zhou
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
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13
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Formin 1-isoform IV deficient cells exhibit defects in cell spreading and focal adhesion formation. PLoS One 2008; 3:e2497. [PMID: 18560567 PMCID: PMC2423616 DOI: 10.1371/journal.pone.0002497] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Accepted: 05/22/2008] [Indexed: 12/23/2022] Open
Abstract
Background Regulation of the cytoskeleton is a central feature of cell migration. The formin family of proteins controls the rate of actin nucleation at its barbed end. Thus, formins are predicted to contribute to several important cell processes such as locomotion, membrane ruffling, vesicle endocytosis, and stress fiber formation and disassociation. Methodology/Principal Findings In this study we investigated the functional role of Formin1-isoform4 (Fmn1-IV) by using genetically null primary cells that displayed augmented protrusive behaviour during wound healing and delayed cell spreading. Cells deficient of Fmn1-IV also showed reduced efficiency of focal adhesion formation. Additionally, we generated an enhanced green fluorescence protein (EGFP)-fused Fmn1-IV knock-in mouse to monitor the endogenous subcellular localization of Fmn1-IV. Its localization was found within the cytoplasm and along microtubules, yet it was largely excluded from adherens junctions. Conclusions/Significance It was determined that Fmn1-IV, as an actin nucleator, contributes to protrusion of the cell's leading edge and focal adhesion formation, thus contributing to cell motility.
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Oeffner F, Moch C, Neundorf A, Hofmann J, Koch M, Grzeschik KH. Novel interaction partners of Bardet-Biedl syndrome proteins. ACTA ACUST UNITED AC 2008; 65:143-55. [DOI: 10.1002/cm.20250] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Loots GG. Genomic identification of regulatory elements by evolutionary sequence comparison and functional analysis. ADVANCES IN GENETICS 2008; 61:269-93. [PMID: 18282510 DOI: 10.1016/s0065-2660(07)00010-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Despite remarkable recent advances in genomics that have enabled us to identify most of the genes in the human genome, comparable efforts to define transcriptional cis-regulatory elements that control gene expression are lagging behind. The difficulty of this task stems from two equally important problems: our knowledge of how regulatory elements are encoded in genomes remains elementary, and there is a vast genomic search space for regulatory elements, since most of mammalian genomes are noncoding. Comparative genomic approaches are having a remarkable impact on the study of transcriptional regulation in eukaryotes and currently represent the most efficient and reliable methods of predicting noncoding sequences likely to control the patterns of gene expression. By subjecting eukaryotic genomic sequences to computational comparisons and subsequent experimentation, we are inching our way toward a more comprehensive catalog of common regulatory motifs that lie behind fundamental biological processes. We are still far from comprehending how the transcriptional regulatory code is encrypted in the human genome and providing an initial global view of regulatory gene networks, but collectively, the continued development of comparative and experimental approaches will rapidly expand our knowledge of the transcriptional regulome.
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Affiliation(s)
- Gabriela G Loots
- Biosciences and Biotechnology Division, Chemistry, Materials and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Kleinjan DA, Lettice LA. Long-range gene control and genetic disease. ADVANCES IN GENETICS 2008; 61:339-88. [PMID: 18282513 DOI: 10.1016/s0065-2660(07)00013-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The past two decades have seen great progress in the elucidation of the genetic basis of human genetic disease. Many clinical phenotypes have been linked with mutations or deletions in specific causative genes. However, it is often less recognized that in addition to the integrity of the protein-coding sequences, human health critically also depends on the spatially, temporally, and quantitatively correct expression of those genes. Genetic disease can therefore equally be caused by disruption of the regulatory mechanisms that ensure proper gene expression. The term "position effect" is used in those situations where the expression level of a gene is deleteriously affected by an alteration in its chromosomal environment, while maintaining an intact transcription unit. Here, we review recent advances in our understanding of the possible mechanisms of a number of "position effect" disease cases and discuss the findings with respect to current models for genome organization and long-range control of gene expression.
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Affiliation(s)
- Dirk A Kleinjan
- MRC Human Genetics Unit, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
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17
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Spitz F, Duboule D. Global control regions and regulatory landscapes in vertebrate development and evolution. ADVANCES IN GENETICS 2008; 61:175-205. [PMID: 18282506 DOI: 10.1016/s0065-2660(07)00006-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
During the course of evolution, many genes that control the development of metazoan body plans were co-opted to exert novel functions, along with the emergence or modification of structures. Gene amplification and/or changes in the cis-regulatory modules responsible for the transcriptional activity of these genes have certainly contributed in a major way to evolution of gene functions. In some cases, these processes led to the formation of groups of adjacent genes that appear to be controlled by both global and shared mechanisms.
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Affiliation(s)
- Francois Spitz
- Developmental Biology Unit, EMBL, 69117 Heidelberg, Germany
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18
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Bradley A, Ramírez-Solis R, Zheng H, Hasty P, Davis A. Genetic manipulation of the mouse via gene targeting in embryonic stem cells. CIBA FOUNDATION SYMPOSIUM 2007; 165:256-69; discussion 269-76. [PMID: 1516472 DOI: 10.1002/9780470514221.ch15] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Gene targeting applied to totipotent embryonic stem (ES) cells is a very powerful means of creating highly specific mutations of genes in the mouse. The successful application of this technology is however constrained by both the types of mutations that can be generated at a target locus and the ability to reconstruct a germline chimera from the manipulated cells. We have developed two cell lines that can be routinely transmitted through the germline of chimeras after cloning and prolonged selection in tissue culture. We have also established a variety of methods for generating non-selected mutations at the X-linked hprt locus in ES cells. Our observations at this locus have enabled us to generate successfully a subtle mutation at the non-selectable Hox-2.6 locus.
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Affiliation(s)
- A Bradley
- Institute for Molecular Genetics, Baylor College of Medicine, Houston, TX 77030
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Robertson EJ, Conlon FL, Barth KS, Costantini F, Lee JJ. Use of embryonic stem cells to study mutations affecting postimplantation development in the mouse. CIBA FOUNDATION SYMPOSIUM 2007; 165:237-50; discussion 250-5. [PMID: 1516471 DOI: 10.1002/9780470514221.ch14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The generation and analysis of insertional mutations that perturb early postimplantation development provide a means to identify genes required at this stage of embryogenesis. We have been studying two independently generated insertional mutations termed 413.d and H beta 58 that result in early postimplantation lethality. Each mutation is associated with a distinct phenotype. 413.d mutant embryos become profoundly abnormal around the time of gastrulation: no identifiable embryonic axis or mesodermal structures are formed. H beta 58 mutant embryos proceed further in development, forming a relatively normal anteroposterior axis before developmental arrest occurs. We isolated embryonic stem cell lines homozygous for each of these mutations and assessed their differentiation abilities and developmental potential in vitro and after their introduction into wild-type blastocysts. From these studies we conclude that the 413.d mutation acts in a non-cell-autonomous fashion: mutant cells appear capable of participating, in conjunction with wild-type cells, in the formation of derivatives of all three primary cell lineages of the embryo. H beta 58 mutant embryonic stem cells are clearly pluripotent but they appear to be more restricted in their developmental potential, suggesting that the H beta 58 gene product may be required by specific tissues of the embryo.
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Affiliation(s)
- E J Robertson
- Department of Genetics & Development, Columbia University College of Physicians & Surgeons, New York NY 10032
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Abstract
Formins constitute a diverse protein family present in all eukaryotes examined. They are defined by the presence of a formin homology 2 (FH2) domain, which possesses intrinsic and conserved functions regulating cytoskeletal dynamics. Over the past few years, formins have become recognized as potent nucleators of linear actin filaments that control a large variety of cellular and morphogenetic functions. Here, we review the molecular principles of formin-induced cytoskeletal rearrangements and their consequences for a growing number of biological processes.
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Affiliation(s)
- Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, 30623 Hannover, Germany.
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Zuniga A. Globalisation reaches gene regulation: the case for vertebrate limb development. Curr Opin Genet Dev 2005; 15:403-9. [PMID: 15979301 DOI: 10.1016/j.gde.2005.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Accepted: 06/07/2005] [Indexed: 10/25/2022]
Abstract
Analysis of key regulators of vertebrate limb development has revealed that the cis-regulatory regions controlling their expression are often located several hundred kilobases upstream of the transcription units. These far up- or down-stream cis-regulatory regions tend to reside within rather large, functionally and structurally unrelated genes. Molecular analysis is beginning to reveal the complexity of these large genomic landscapes, which control the co-expression of clusters of diverse genes by this novel type of long-range and globally acting cis-regulatory region. An increasing number of spontaneous mutations in vertebrates, including humans, are being discovered inactivating or altering such global control regions. Thereby, the functions of a seemingly distant but essential gene are disrupted rather than the closest.
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Affiliation(s)
- Aimée Zuniga
- Developmental Genetics, DKBW Centre for Biomedicine, University of Basel Medical School, Mattenstrasse 28, CH-4058 Basel, Switzerland.
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22
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Badour K, Zhang J, Siminovitch KA. Involvement of the Wiskott-Aldrich syndrome protein and other actin regulatory adaptors in T cell activation. Semin Immunol 2005; 16:395-407. [PMID: 15541654 DOI: 10.1016/j.smim.2004.08.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The actin cytoskeleton is a dynamic structure recognized for many years as integral to the coupling of external stimuli to cell activation and ensuing changes in morphology and movement. It is only recently, however, that a molecular understanding of actin involvement in these activities has emerged coincident with the identification of cytosolic signaling effectors that couple extracellular stimuli to induction of actin nucleation. Notable among these actin regulatory effectors are members of the Wiskott-Aldrich syndrome protein (WASp) family, a group of cytoskeletal adaptors imbued with the capacity to connect various signal transduction pathways to the Arp 2/3 complex and Arp 2/3-mediated actin polymerization. In T cells, the functional characterization of WASp and other actin-modulatory adaptors has proved instrumental in delineating the molecular interactions evoking actin cytoskeletal reorganization downstream of antigen receptor engagement and in clarifying the influence of actin-based processes on T cell activation. In this review, the structural and functional properties of the major actin regulatory cytoskeletal adaptors in T cells are described with an emphasis on the roles of these proteins in fostering the TCR actin cytoskeletal interplay required for induction of T cell activation and expression of dynamic effector responses.
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Affiliation(s)
- Karen Badour
- Department of Medicine, McLaughlin Centre of Molecular Medicine, University of Toronto, Mount Sinai Hospital, Samuel Lunenfeld and Toronto General Hospital Research Institutes, 600 University Avenue, #656A, Toronto, Ont., Canada M5G 1X5.
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23
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Lettice LA, Kapoor T, Hill RE. Digital dialogues in Dundee: 8th International Conference on Limb Development. Dev Dyn 2005; 233:252-5. [PMID: 15768402 DOI: 10.1002/dvdy.20315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Laura A Lettice
- MRC-Human Genetics Unit, Western General Hospital, Edinburgh, United Kingdom
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24
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Kleinjan DA, van Heyningen V. Long-range control of gene expression: emerging mechanisms and disruption in disease. Am J Hum Genet 2005; 76:8-32. [PMID: 15549674 PMCID: PMC1196435 DOI: 10.1086/426833] [Citation(s) in RCA: 645] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 10/08/2004] [Indexed: 02/04/2023] Open
Abstract
Transcriptional control is a major mechanism for regulating gene expression. The complex machinery required to effect this control is still emerging from functional and evolutionary analysis of genomic architecture. In addition to the promoter, many other regulatory elements are required for spatiotemporally and quantitatively correct gene expression. Enhancer and repressor elements may reside in introns or up- and downstream of the transcription unit. For some genes with highly complex expression patterns--often those that function as key developmental control genes--the cis-regulatory domain can extend long distances outside the transcription unit. Some of the earliest hints of this came from disease-associated chromosomal breaks positioned well outside the relevant gene. With the availability of wide-ranging genome sequence comparisons, strong conservation of many noncoding regions became obvious. Functional studies have shown many of these conserved sites to be transcriptional regulatory elements that sometimes reside inside unrelated neighboring genes. Such sequence-conserved elements generally harbor sites for tissue-specific DNA-binding proteins. Developmentally variable chromatin conformation can control protein access to these sites and can regulate transcription. Disruption of these finely tuned mechanisms can cause disease. Some regulatory element mutations will be associated with phenotypes distinct from any identified for coding-region mutations.
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Affiliation(s)
- Dirk A Kleinjan
- MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, Scotland, United Kingdom
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25
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Watanabe N, Higashida C. Formins: processive cappers of growing actin filaments. Exp Cell Res 2004; 301:16-22. [PMID: 15501440 DOI: 10.1016/j.yexcr.2004.08.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Indexed: 11/19/2022]
Abstract
Taking the advantage of single-molecule imaging, our recent study has revealed surprisingly long processive movement of a Formin protein, mDia1, surfing along with the growing end of actin filaments in living cells. This finding provides direct evidence for the ability of Formins to function as processive cappers that has been postulated from several lines of evidence in biochemical studies. With nucleating filaments from the profilin-actin pool, Formins may effectively generate long actin filaments, and contribute to the generation of the specific actin-based structures, that is, the contractile ring in cytokinesis, actin stress fibers in animal cells, and yeast actin cables. Furthermore, Formins have the potential to function as actin polymerization-driven molecular motors. Although much remains to be tested about the role of this novel molecular mobilization mechanism, cells might utilize actin polymerization energy for cell shape change and/or trafficking via Formin motors.
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Affiliation(s)
- Naoki Watanabe
- Department of Pharmacology, Kyoto University, Faculty of Medicine, Kyoto 606-8501, Japan.
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26
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Schumacher N, Borawski JM, Leberfinger CB, Gessler M, Kerkhoff E. Overlapping expression pattern of the actin organizers Spir-1 and formin-2 in the developing mouse nervous system and the adult brain. Gene Expr Patterns 2004; 4:249-55. [PMID: 15053972 DOI: 10.1016/j.modgep.2003.11.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2003] [Revised: 10/14/2003] [Accepted: 11/18/2003] [Indexed: 10/26/2022]
Abstract
The Wiskott-Aldrich homology domain 2 (WH2) family protein Spir and the formin Cappuccino belong to two distinct classes of actin organizers. Despite their functional classification as actin organizers, a major defect of Drosophila spire and cappuccino mutant oocytes is a failure in the orientation of microtubule plus ends towards the posterior pole. Mammalian homologues of spire are the spir-1 and spir-2 genes. The mouse and human formin-1 and formin-2 genes have high similarity to the cappuccino gene. The mouse formin-2 gene has been found to be expressed in the developing nervous system and in neuronal cells of the adult brain. By analyzing the expression of the spir-1 gene we show that spir-1 and formin-2 have a nearly identical expression pattern during mouse embryogenesis and in the adult brain. In mouse embryos both genes are expressed in the developing nervous system. In the adult brain high expression of the genes was found in the Purkinje cells of the cerebellum and in neuronal cells of the hippocampus and dentate gyrus.
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Affiliation(s)
- Nina Schumacher
- Theodor-Boveri-Institut (Biozentrum), Universität Würzburg, Physiologische Chemie I, Am Hubland, 97074 Würzburg, Germany
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27
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Zuniga A, Michos O, Spitz F, Haramis APG, Panman L, Galli A, Vintersten K, Klasen C, Mansfield W, Kuc S, Duboule D, Dono R, Zeller R. Mouse limb deformity mutations disrupt a global control region within the large regulatory landscape required for Gremlin expression. Genes Dev 2004; 18:1553-64. [PMID: 15198975 PMCID: PMC443518 DOI: 10.1101/gad.299904] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mouse limb deformity (ld) mutations cause limb malformations by disrupting epithelial-mesenchymal signaling between the polarizing region and the apical ectodermal ridge. Formin was proposed as the relevant gene because three of the five ld alleles disrupt its C-terminal domain. In contrast, our studies establish that the two other ld alleles directly disrupt the neighboring Gremlin gene, corroborating the requirement of this BMP antagonist for limb morphogenesis. Further doubts concerning an involvement of Formin in the ld limb phenotype are cast, as a targeted mutation removing the C-terminal Formin domain by frame shift does not affect embryogenesis. In contrast, the deletion of the corresponding genomic region reproduces the ld limb phenotype and is allelic to mutations in Gremlin. We resolve these conflicting results by identifying a cis-regulatory region within the deletion that is required for Gremlin activation in the limb bud mesenchyme. This distant cis-regulatory region within Formin is also altered by three of the ld mutations. Therefore, the ld limb bud patterning defects are not caused by disruption of Formin, but by alteration of a global control region (GCR) required for Gremlin transcription. Our studies reveal the large genomic landscape harboring this GCR, which is required for tissue-specific coexpression of two structurally and functionally unrelated genes.
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Affiliation(s)
- Aimée Zuniga
- Developmental Genetics, Department of Clinical-Biological Sciences, University of Basel Medical School, CH-4056 Basel, Switzerland
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28
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Westendorf JJ, Koka S. Identification of FHOD1-binding proteins and mechanisms of FHOD1-regulated actin dynamics. J Cell Biochem 2004; 92:29-41. [PMID: 15095401 DOI: 10.1002/jcb.20031] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Formin homology-2-domain containing protein 1 (FHOD1) regulates gene transcription, actin-cytoskeleton structure, and cell migration. To gain insight into the mechanisms by which FHOD1 mediates these diverse activities, a yeast-two-hybrid screen was performed to identify FHOD1-binding proteins. Three proteins specifically interacted with the carboxy-terminal two-thirds of FHOD1, which includes the FH1, FH2, and diaphanous activating domains (DAD). The newly identified FHOD1-binding proteins are protein kinase C binding protein 1 (PRKCBP1), cyclophilin B, and an isoform of WASP-interacting SH3-domain protein/diaphanous-interacting protein 1 (WISH/DIP1), named WISH-B. The proline-rich FH1 domain of FHOD1 was sufficient to interact with the central portion of PRKCP1 and full-length cyclophilin B. The FH1 domain also interacted with full-length WISH-B, but the extreme amino-terminus was sufficient to associate with WISH-B as well. WISH-B altered the solubility of FHOD1 in vitro and a truncation mutant containing the amino-terminal 227 residues of WISH-B disrupted FHOD1-induced stress fibers. WISH-B did not affect FHOD1-induced gene transcription through the serum response factor (SRF) recognition site on the skeletal alpha actin promoter (SkA). However, stabilization of F-actin prevented FHOD1 dependent activation of this promoter in presence of high, but not low serum concentrations. Thus, the identification of a new FHOD1-binding protein provides insight into the mechanisms by which FHOD1 regulates actin polymerization and transcription.
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Affiliation(s)
- Jennifer J Westendorf
- The Cancer Center and Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, Minnesota, USA.
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29
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Kobielak A, Pasolli HA, Fuchs E. Mammalian formin-1 participates in adherens junctions and polymerization of linear actin cables. Nat Cell Biol 2003; 6:21-30. [PMID: 14647292 PMCID: PMC2605950 DOI: 10.1038/ncb1075] [Citation(s) in RCA: 292] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Accepted: 11/11/2003] [Indexed: 11/09/2022]
Abstract
During epithelial sheet formation, linear actin cables assemble at nascent adherens junctions. This process requires alpha-catenin and actin polymerization, although the underlying mechanism is poorly understood. Here, we show that formin-1 interacts with alpha-catenin, localizes to adherens junctions and nucleates unbranched actin filaments. Furthermore, disruption of the alpha-catenin-formin-1 interaction blocks assembly of radial actin cables and perturbs intercellular adhesion. A fusion protein of the beta-catenin-binding domain of alpha-catenin with the actin polymerization domains of formin-1 rescues formation of adherens junctions and associated actin cables in alpha-catenin-null keratinocytes. These findings provide new insight into how alpha-catenin orchestrates actin dynamics during intercellular junction formation.
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Affiliation(s)
- Agnieszka Kobielak
- Howard Hughes Medical Institute, Laboratory of Mammalian Cell Biology and Development, The Rockefeller University, 1230 York Avenue, Box 300, New York, NY 10021-6399, USA
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30
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Dolan V, Murphy M, Alarcon P, Brady HR, Hensey C. Gremlin - a putative pathogenic player in progressive renal disease. Expert Opin Ther Targets 2003; 7:523-6. [PMID: 12885271 DOI: 10.1517/14728222.7.4.523] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Progressive renal fibrosis is the end process of renal injury leading to kidney failure. Current therapies for chronic renal failure aim to slow this process but fail to halt its progression. As the mechanisms involved in glomerulosclerosis and tubulointerstitial fibrosis are unravelled, potential treatments for this growing clinical problem should emerge. Gremlin, a developmental regulator of bone morphogenetic proteins (BMPs), has recently been implicated in processes such as glomerulosclerosis, tubulointerstitial fibrosis and cellular hypertrophy, and may represent a novel therapeutic target in progressive renal diseases.
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MESH Headings
- Animals
- Bone Morphogenetic Proteins/antagonists & inhibitors
- Bone Morphogenetic Proteins/physiology
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/physiopathology
- Diabetic Nephropathies/genetics
- Diabetic Nephropathies/physiopathology
- Dimerization
- Disease Progression
- Feedback, Physiological
- Fibrosis
- Gene Expression Regulation
- Glomerulosclerosis, Focal Segmental/genetics
- Glomerulosclerosis, Focal Segmental/physiopathology
- Hedgehog Proteins
- Humans
- Hypertrophy
- Intercellular Signaling Peptides and Proteins/genetics
- Intercellular Signaling Peptides and Proteins/physiology
- Kidney Diseases/etiology
- Kidney Diseases/physiopathology
- Kidney Failure, Chronic/etiology
- Kidney Failure, Chronic/physiopathology
- Kidney Glomerulus/metabolism
- Mice
- Mice, Knockout
- Nephritis, Interstitial/genetics
- Nephritis, Interstitial/physiopathology
- Rats
- Trans-Activators/physiology
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Affiliation(s)
- Vincent Dolan
- Centre for Integrative Biology, Conway Institute of Biomolecular and Biomedical Research, Department of Medicine and Therapeutics, University College Dublin, The Dulin Molecular Medicine Centre, Belfield, Ireland.
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31
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Evangelista M, Zigmond S, Boone C. Formins: signaling effectors for assembly and polarization of actin filaments. J Cell Sci 2003; 116:2603-11. [PMID: 12775772 DOI: 10.1242/jcs.00611] [Citation(s) in RCA: 226] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Eukaryotic cells require filamentous actin to maintain their shape and for movement, growth and replication. New actin filaments are formed by the cutting of existing filaments or de novo through the action of specialized nucleators. The most highly characterized nucleator is the Arp2/3 complex, which nucleates the branched actin networks in the lamellae of migrating cells. Recently, Bni1p, which is a member of the formin family of proteins, has been shown to nucleate actin filaments in vitro. Formins are implicated in the formation of actin cables in yeast, stress fibers in tissue culture cells and cytokinesis in many cell types. Formins contain two highly conserved formin-homology domains, FH1 and FH2. The Bni1p FH2 domain is sufficient to mediate nucleation. The Bni1p FH1 domain binds profilin, an actin-monomer-binding protein that delivers actin to the growing barbed end of filaments. The Bni1p FH1-profilin interaction enhances nucleation. Formins participate in a number of signaling pathways that control the assembly of specific actin structures and bind the barbed end of actin filaments, thereby providing a cytoskeletal basis for the establishment of cell polarity.
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Affiliation(s)
- Marie Evangelista
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
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32
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Khokha MK, Hsu D, Brunet LJ, Dionne MS, Harland RM. Gremlin is the BMP antagonist required for maintenance of Shh and Fgf signals during limb patterning. Nat Genet 2003; 34:303-7. [PMID: 12808456 DOI: 10.1038/ng1178] [Citation(s) in RCA: 278] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2003] [Accepted: 05/15/2003] [Indexed: 11/09/2022]
Abstract
During limb outgrowth, signaling by bone morphogenetic proteins (BMPs) must be moderated to maintain the signaling loop between the zone of polarizing activity (ZPA) and the apical ectodermal ridge (AER). Gremlin, an extracellular Bmp antagonist, has been proposed to fulfill this function and therefore be important in limb patterning. We tested this model directly by mutating the mouse gene encoding gremlin (Cktsf1b1, herein called gremlin). In the mutant limb, the feedback loop between the ZPA and the AER is interrupted, resulting in abnormal skeletal pattern. We also show that the gremlin mutation is allelic to the limb deformity mutation (ld). Although Bmps and their antagonists have multiple roles in limb development, these experiments show that gremlin is the principal BMP antagonist required for early limb outgrowth and patterning.
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Affiliation(s)
- Mustafa K Khokha
- Department of Molecular and Cell Biology, University of California-Berkeley, 401 Barker Hall, Berkeley, California 94720, USA
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33
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Koka S, Neudauer CL, Li X, Lewis RE, McCarthy JB, Westendorf JJ. The formin-homology-domain-containing protein FHOD1 enhances cell migration. J Cell Sci 2003; 116:1745-55. [PMID: 12665555 DOI: 10.1242/jcs.00386] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Formin-homology-domain-containing proteins interact with Rho-family GTPases and regulate actin cytoskeleton organization and gene transcription. FHOD1 is a member of this family, interacts with Rac1 and induces transcription from the serum response element. In this study, we examined the effects of FHOD1 expression on cytoskeletal organization and function in mammalian cells. FHOD1 proteins were stably expressed in WM35 melanoma cells and NIH-3T3 fibroblasts. Cells expressing full-length FHOD1 demonstrated an elongated phenotype compared with vector-transfected cells and cells expressing a truncated FHOD1 (1-421) that lacks the conserved FH1 and FH2 domains. Full-length FHOD1 co-localized with filamentous actin at cell peripheries. Cells transiently expressing a C-terminal FHOD1 truncation mutant (DeltaC, residues 1-1010), which lacks an autoinhibitory protein-protein interaction domain, displayed prominent stress fibers. FHOD1 (1-421) did not induce stress fibers but localized to membrane ruffles in a manner similar to the full-length protein, indicating that the FH1 and FH2 domains are required for stress fiber appearance. FHOD1 DeltaC (1-1010)-dependent stress fibers were sensitive to dominant-negative RacN17 and the RhoA and ROCK inhibitors, C3 transferase and Y-27632. Stable overexpression of full-length FHOD1 enhanced the migration of WM35 and NIH-3T3 cells to type-I collagen and fibronectin, respectively. Cells expressing FHOD1 (1-421) migrated similar to control cells. Integrin expression and activation were not affected by FHOD1 expression. Moreover, FHOD1 overexpression did not alter integrin usage during adhesion or migration. These data demonstrate that FHOD1 interacts with and regulates the structure of the cytoskeleton and stimulates cell migration in an integrin-independent manner.
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Affiliation(s)
- Sreenivas Koka
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Lincoln, NE 68583, USA
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34
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Balemans W, Van Hul W. Extracellular regulation of BMP signaling in vertebrates: a cocktail of modulators. Dev Biol 2002. [PMID: 12376100 DOI: 10.1006/dbio.2002.0779] [Citation(s) in RCA: 427] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The transforming growth factor-beta (TGF-beta) superfamily contains a variety of growth factors which all share common sequence elements and structural motifs. These proteins are known to exert a wide spectrum of biological responses on a large variety of cell types in both vertebrates and invertebrates. Many of them have important functions during embryonic development in pattern formation and tissue specification, and in adult tissues, they are involved in processes such as wound healing, bone repair, and bone remodeling. The family is divided into two general branches: the BMP/GDF and the TGF-beta/Activin/Nodal branches, whose members have diverse, often complementary effects. It is obvious that an orchestered regulation of different actions of these proteins is necessary for proper functioning. The TGF-beta family members act by binding extracellularly to a complex of serine/threonine kinase receptors, which consequently activate Smad molecules by phosphorylation. These Smads translocate to the nucleus, where they modulate transcription of specific genes. Three levels by which this signaling pathway is regulated could be distinguished. First, a control mechanism exists in the intracellular space, where inhibitory Smads and Smurfs prevent further signaling and activation of target genes. Second, at the membrane site, the pseudoreceptor BAMBI/Nma is able to inhibit further signaling within the cells. Finally, a range of extracellular mediators are identified which modulate the functioning of members of the TGF-beta superfamily. Here, we review the insights in the extracellular regulation of members of the BMP subfamily of secreted growth factors with a major emphasis on vertebrate BMP modulation.
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Affiliation(s)
- Wendy Balemans
- Department of Medical Genetics, University of Antwerp and University Hospital, Antwerp 2610, Belgium
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35
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Sagot I, Klee SK, Pellman D. Yeast formins regulate cell polarity by controlling the assembly of actin cables. Nat Cell Biol 2002; 4:42-50. [PMID: 11740491 DOI: 10.1038/ncb719] [Citation(s) in RCA: 309] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Formins are conserved Rho-GTPase effectors that communicate Rho-GTPase signals to the cytoskeleton. We found that formins were required for the assembly of one of the three budding yeast actin structures: polarized arrays of actin cables. A dominant-active formin induced the assembly of actin cables. The activation and localization of the formin Bni1p required components of the polarisome complex. These findings potentially define the cellular function of formins in budding yeast and explain their involvement in the generation of cell polarity. A requirement for formins in constructing specific actin structures might be the basis for the diverse activities of formins in development.
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Affiliation(s)
- Isabelle Sagot
- Department of Pediatric Hematology/Oncology, The Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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36
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Westendorf JJ. The formin/diaphanous-related protein, FHOS, interacts with Rac1 and activates transcription from the serum response element. J Biol Chem 2001; 276:46453-9. [PMID: 11590143 DOI: 10.1074/jbc.m105162200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
FHOS is a member of the formin homology (FH) family of proteins and is expressed at high levels in splenic cells. FH proteins link cellular signaling pathways to the actin cytoskeleton and serum response factor-dependent transcription. In these studies, the role of FHOS in Rho family GTPase signaling pathways was analyzed. FHOS interacted with the polybasic domain in the Rac1 C terminus in a guanine nucleotide-independent manner but did not interact with RhoA, Cdc42Hs, Rac2, or Rac3. Intramolecular autoinhibitory interactions between the C terminus of FHOS and an N-terminal region partially overlapping the Rac1 interaction domain were also identified. FHOS truncation mutants lacking the N- or C-terminal autoregulatory domains stimulated transcription of a c-fos serum response element (SRE)-driven reporter. Overexpression of wild-type and mutant (N17 and V12) Rac1 proteins repressed SRE induction by the N-terminal FHOS deletion mutant but not by the C-terminal FHOS deletion mutant. Immunofluorescence studies indicated that the localization of the mutant FHOS proteins might contribute to their differential responses to Rac1. Wild-type FHOS and the N-terminal deletion mutant localized to the perinuclear region and membrane edges. In contrast, the C-terminal FHOS mutants were diffusely localized. These data suggest that FHOS induces transcription from SREs by multiple pathways and that Rac1 may influence the course of some FHOS-induced signaling events.
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Affiliation(s)
- J J Westendorf
- Department of Orthopaedic Surgery and University of Minnesota Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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37
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Fuchs U, Rehkamp G, Haas OA, Slany R, Kōnig M, Bojesen S, Bohle RM, Damm-Welk C, Ludwig WD, Harbott J, Borkhardt A. The human formin-binding protein 17 (FBP17) interacts with sorting nexin, SNX2, and is an MLL-fusion partner in acute myelogeneous leukemia. Proc Natl Acad Sci U S A 2001; 98:8756-61. [PMID: 11438682 PMCID: PMC37508 DOI: 10.1073/pnas.121433898] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have cloned a fusion partner of the MLL gene at 11q23 and identified it as the gene encoding the human formin-binding protein 17, FBP17. It maps to chromosome 9q34 centromeric to ABL. The gene fusion results from a complex chromosome rearrangement that was resolved by fluorescence in situ hybridization with various probes on chromosomes 9 and 11 as an ins(11;9)(q23;q34)inv(11)(q13q23). The rearrangement resulted in a 5'-MLL/FBP17-3' fusion mRNA. We retrovirally transduced murine-myeloid progenitor cells with MLL/FBP17 to test its transforming ability. In contrast to MLL/ENL, MLL/ELL and other MLL-fusion genes, MLL/FBP17 did not give a positive readout in a serial replating assay. Therefore, we assume that additional cooperating genetic abnormalities might be needed to establish a full malignant phenotype. FBP17 consists of a C-terminal Src homology 3 domain and an N-terminal region that is homologous to the cell division cycle protein, cdc15, a regulator of the actin cytoskeleton in Schizosaccharomyces pombe. Both domains are separated by a consensus Rho-binding motif that has been identified in different Rho-interaction partners such as Rhotekin and Rhophilin. We evaluated whether FBP17 and members of the Rho family interact in vivo with a yeast two-hybrid assay. None of the various Rho proteins tested, however, interacted with FBP17. We screened a human kidney library and identified a sorting nexin, SNX2, as a protein interaction partner of FBP17. These data provide a link between the epidermal growth factor receptor pathway and an MLL fusion protein.
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MESH Headings
- Artificial Gene Fusion
- Base Sequence
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Nucleus/metabolism
- Cell Transformation, Neoplastic
- Chromosome Mapping
- Chromosomes, Human, Pair 9
- DNA, Complementary
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Fatty Acid-Binding Proteins
- Histone-Lysine N-Methyltransferase
- Humans
- In Situ Hybridization, Fluorescence/methods
- Infant
- Leukemia, Myelomonocytic, Acute/genetics
- Leukemia, Myelomonocytic, Acute/metabolism
- Leukemia, Myelomonocytic, Acute/pathology
- Male
- Molecular Sequence Data
- Myeloid-Lymphoid Leukemia Protein
- Proto-Oncogenes
- Tissue Distribution
- Transcription Factors
- Vesicular Transport Proteins
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Affiliation(s)
- U Fuchs
- Department of Pediatric Hematology and Oncology, University of Giessen, 35392 Giessen, Germany
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38
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O'Rourke DA, Liu ZX, Sellin L, Spokes K, Zeller R, Cantley LG. Hepatocyte growth factor induces MAPK-dependent formin IV translocation in renal epithelial cells. J Am Soc Nephrol 2000; 11:2212-2221. [PMID: 11095644 DOI: 10.1681/asn.v11122212] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Renal epithelial tubule formation in cultured cells occurs after the addition of tubulogenic growth factors such as the hepatocyte growth factor (HGF). HGF activates the tyrosine kinase receptor c-met, initiating a series of complex events that regulate cell morphology, cell-cell interactions, and cell-matrix interactions and eventually result in the formation of branching tubular structures. The discovery that disruption of the formin gene locus in mice causes agenesis of the kidneys secondary to failure of ureteric bud outgrowth and branching tubule formation suggested that this family of proteins may be critical to the development of renal epithelial tubules. In this study, we investigated whether formin is involved in the HGF/c-met signaling pathway of in vitro tubulogenesis in renal epithelial cells. mIMCD-3 cells were analyzed by reverse transcription-PCR and found to express formin IV mRNA. With the use of an antibody that recognizes the carboxy terminus of all known formin isoforms, it was observed a formin isoform of approximately 165 kD markedly increased in the detergent soluble cell lysate after 10 min of stimulation with HGF. An antibody that is specific for formin IV was then generated and confirmed that the formin isoform regulated by HGF was formin IV. Cell fractionation and confocal localization of formin IV revealed that formin IV is primarily found in a submembranous band that co-localizes with the actin cytoskeleton and in a perinuclear location in quiescent epithelial cells but undergoes a rapid relocalization after HGF stimulation with translocation into the cell cytosol and into the nucleus. Formin IV was found to be a phosphorylation substrate for activated extracellular signal-regulated kinase in vitro, and pretreatment of cells with the mitogen-activated protein kinase inhibitor U0126 prevented the translocation of formin IV and inhibited HGF-dependent phosphorylation of formin IV in intact cells. In conclusion, activation of the c-met receptor results in cellular relocalization of formin IV in a mitogen-activated protein kinase-dependent manner.
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Affiliation(s)
| | - Zhen-Xiang Liu
- Section of Nephrology, Yale University, School of Medicine, New Haven, Connecticut
| | - Lorenz Sellin
- Section of Nephrology, University of Freiburg, Freiburg, Germany
| | - Katherine Spokes
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Rolf Zeller
- University of Utrecht, Utrecht, The Netherlands
| | - Lloyd G Cantley
- Section of Nephrology, Yale University, School of Medicine, New Haven, Connecticut
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39
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Schaerer-Brodbeck C, Riezman H. Interdependence of filamentous actin and microtubules for asymmetric cell division. Biol Chem 2000; 381:815-25. [PMID: 11076014 DOI: 10.1515/bc.2000.104] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Asymmetric cell divisions are crucial to the generation of cell fate diversity. They contribute to unequal distribution of cellular factors to the daughter cells. Asymmetric divisions are characterized by a 90 degrees rotation of the mitotic spindle. There is increasing evidence that a tight cooperation between cortical, filamentous actin and astral microtubules is indispensable for successful spindle rotation. Over the past years, the dynactin complex has emerged as a key candidate to mediate actin/microtubule interaction at the cortex. This review discusses our current understanding of how spindle rotation is accomplished by the interplay of filamentous actin and microtubules in a variety of experimental systems.
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40
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Leader B, Leder P. Formin-2, a novel formin homology protein of the cappuccino subfamily, is highly expressed in the developing and adult central nervous system. Mech Dev 2000; 93:221-31. [PMID: 10781961 DOI: 10.1016/s0925-4773(00)00276-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Formin-1 is the founding member of a family of genes of emerging biological and medical importance that share specific domains of homology, allowing them to be classified together as the formin homology proteins. Although deficiency mutations in formin-1 lead to profound developmental defects in limb and kidney formation, similar deficiency mutations in more distantly related members of this family (diaphanous and cappuccino in Drosophila and BNI1 in yeast) have ostensibly unrelated phenotypes. Here we describe murine and human formin-2 (Fmn2), a gene which bears a high degree of similarity to formin-1 and cappuccino. The mouse gene, which encodes a putative 1567-amino-acid open reading frame and maps to mouse Chromosome 1, is expressed almost exclusively in the developing and mature central nervous system. Expression begins at embryonic day 9. 5 in the developing spinal cord and brain structures and continues in neonatal and adult brain structures including the olfactory bulb, cortex, thalamus, hypothalamus, hippocampus and cerebellum. Human formin-2 has a similar expression pattern.
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Affiliation(s)
- B Leader
- Department of Genetics, Harvard Medical School, Howard Hughes Medical Institute, Boston, MA 02115, USA.
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41
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Magie CR, Meyer MR, Gorsuch MS, Parkhurst SM. Mutations in the Rho1 small GTPase disrupt morphogenesis and segmentation during early Drosophila development. Development 1999; 126:5353-64. [PMID: 10556060 DOI: 10.1242/dev.126.23.5353] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Rho GTPases play an important role in diverse biological processes such as actin cytoskeleton organization, gene transcription, cell cycle progression and adhesion. They are required during early Drosophila development for proper execution of morphogenetic movements of individual cells and groups of cells important for the formation of the embryonic body plan. We isolated loss-of-function mutations in the Drosophila Rho1 (Rho1) gene during a genetic screen for maternal-effect mutations, allowing us to investigate the specific roles Rho1 plays in the context of the developing organism. Here we report that Rho1 is required for many early events: loss of Rho1 function results in both maternal and embryonic phenotypes. Embryos homozygous for the Rho1 mutation exhibit a characteristic zygotic phenotype, which includes severe defects in head involution and imperfect dorsal closure. Two phenotypes are associated with reduction of maternal Rho1 activity: the actin cytoskeleton is disrupted in egg chambers, especially in the ring canals and embryos display patterning defects as a result of improper maintenance of segmentation gene expression. Despite showing imperfect dorsal closure, Rho1 does not activate downstream genes or interact genetically with members of the JNK signaling pathway, used by its relatives dRac and dCdc42 for proper dorsal closure. Consistent with its roles in regulating actin cytoskeletal organization, we find that Rho1 interacts genetically and physically with the Drosophila formin homologue, cappuccino. We also show that Rho1 interacts both genetically and physically with concertina, a G(alpha) protein involved in cell shape changes during gastrulation.
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Affiliation(s)
- C R Magie
- Division of Basic Sciences and Program in Developmental Biology, A1-162, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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42
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Zúñiga A, Haramis AP, McMahon AP, Zeller R. Signal relay by BMP antagonism controls the SHH/FGF4 feedback loop in vertebrate limb buds. Nature 1999; 401:598-602. [PMID: 10524628 DOI: 10.1038/44157] [Citation(s) in RCA: 379] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Outgrowth and patterning of the vertebrate limb are controlled by reciprocal interactions between the posterior mesenchyme (polarizing region) and a specialized ectodermal structure, the apical ectodermal ridge (AER). Sonic hedgehog (SHH) signalling by the polarizing region modulates fibroblast growth factor (FGF)4 signalling by the posterior AER, which in turn maintains the polarizing region (SHH/FGF4 feedback loop). Here we report that the secreted bone-morphogenetic-protein (BMP) antagonist Gremlin relays the SHH signal from the polarizing region to the AER. Mesenchymal Gremlin expression is lost in limb buds of mouse embryos homozygous for the limb deformity (Id) mutation, which disrupts establishment of the SHH/FGF4 feedback loop. Grafting Gremlin-expressing cells into ld mutant limb buds rescues Fgf4 expression and restores the SHH/FGF4 feedback loop. Analysis of Shh-null mutant embryos reveals that SHH signalling is required for maintenance of Gremlin and Formin (the gene disrupted by the ld mutations). In contrast, Formin, Gremlin and Fgf4 activation are independent of SHH signalling. This study uncovers the cascade by which the SHH signal is relayed from the posterior mesenchyme to the AER and establishes that Formin-dependent activation of the BMP antagonist Gremlin is sufficient to induce Fgf4 and establish the SHH/FGF4 feedback loop.
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Affiliation(s)
- A Zúñiga
- Department of Developmental Biology, Faculty of Biology, Utrecht University, The Netherlands
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43
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Westendorf JJ, Mernaugh R, Hiebert SW. Identification and characterization of a protein containing formin homology (FH1/FH2) domains. Gene 1999; 232:173-82. [PMID: 10352228 DOI: 10.1016/s0378-1119(99)00127-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A novel member of the Formin/Diaphanous family of proteins was cloned and characterized. A 4kB mRNA is ubiquitously expressed but is found in abundance in the spleen. FHOS (Formin Homologue Overexpressed in Spleen) contains a 3414bp open reading frame and encodes for an approximately 128kDa protein. FHOS has sequence homology to Diaphanous and Formin proteins within the Formin Homology (FH)1 and FH2 domains. FHOS also contains a coiled-coil, a collagen-like domain, two nuclear localization signals, and several potential PKC and PKA phosphorylation sites. FHOS-specific antiserum was generated and used to determine that FHOS is a predominantly cytoplasmic protein and is expressed in a variety of human cell lines. FHOS was mapped to chromosome 16q22 between framework markers WI-5594 and WI-9392.
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Affiliation(s)
- J J Westendorf
- Vanderbilt University, Department of Biochemistry and Vanderbilt Cancer Center, Nashville, TN 37232, USA
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44
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Abstract
Eukaryotic cells respond to intracellular and extracellular cues to direct asymmetric cell growth and division. The yeast Saccharomyces cerevisiae undergoes polarized growth at several times during budding and mating and is a useful model organism for studying asymmetric growth and division. In recent years, many regulatory and cytoskeletal components important for directing and executing growth have been identified, and molecular mechanisms have been elucidated in yeast. Key signaling pathways that regulate polarization during the cell cycle and mating response have been described. Since many of the components important for polarized cell growth are conserved in other organisms, the basic mechanisms mediating polarized cell growth are likely to be universal among eukaryotes.
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Affiliation(s)
- K Madden
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA
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45
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Zúñiga A, Zeller R. Gli3 (Xt) and formin (ld) participate in the positioning of the polarising region and control of posterior limb-bud identity. Development 1999; 126:13-21. [PMID: 9834182 DOI: 10.1242/dev.126.1.13] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
During initiation of limb-bud outgrowth in vertebrate embryos, the polarising region (limb-bud organizer) is established upon activation of the Sonic Hedgehog (SHH) signaling molecule at the posterior limb-bud margin. Another hallmark of establishing anteroposterior limb-bud identities is the colinear activation of HoxD genes located at the 5′ end of the cluster (5′HoxD genes). The unique and shared functions of Gli3 and formin in these determinative events were genetically analyzed using single and double homozygous Extra-toes (Xt; disrupting Gli3) and limb deformity (ld; disrupting formin) mouse embryos. Analysis of the limb skeletal phenotypes reveals genetic interaction of the two genes. In addition to loss of digit identity and varying degrees of polydactyly, proximal skeletal elements are severely shortened in Xt;ld double homozygous limbs. The underlying molecular defects affect both establishment of the polarising region and posterior limb-bud identity. In particular, the synergism between Gli3- and formin-mediated mesenchyme-AER interactions positions the SHH signaling center at the posterior limb-bud margin. The present study shows that establishment and positioning of the polarising region is regulated both by restriction of Shh through Gli3 and its positive feedback regulation through formin. Concurrently, Gli3 functions independently of formin during initial posterior nesting of 5′HoxD domains, whereas their subsequent distal restriction and anterior expansion depends on genetic interaction of Gli3 and formin.
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Affiliation(s)
- A Zúñiga
- EMBL, Meyerhofstrasse 1, D-69117 Heidelberg, Germany
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46
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Abstract
We present a review of limb development integrating current molecular information and selected genetic disorders to illustrate the advances made in this field over the last few years. With this knowledge, clinical geneticists can now begin to consider molecular mechanisms and pathways when investigating patients with limb malformation syndromes.
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Affiliation(s)
- J W Innis
- University of Michigan, Department of Human Genetics, Ann Arbor 48109-0618, USA.
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47
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Bione S, Sala C, Manzini C, Arrigo G, Zuffardi O, Banfi S, Borsani G, Jonveaux P, Philippe C, Zuccotti M, Ballabio A, Toniolo D. A human homologue of the Drosophila melanogaster diaphanous gene is disrupted in a patient with premature ovarian failure: evidence for conserved function in oogenesis and implications for human sterility. Am J Hum Genet 1998; 62:533-41. [PMID: 9497258 PMCID: PMC1376955 DOI: 10.1086/301761] [Citation(s) in RCA: 194] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Premature ovarian failure (POF) is a defect of ovarian development and is characterized by primary or secondary amenorrhea, with elevated levels of serum gonadotropins, or by early menopause. The disorder has been attributed to various causes, including rearrangements of a large "critical region" in the long arm of the X chromosome. Here we report identification, in a family with POF, of a gene that is disrupted by a breakpoint. The gene is the human homologue of the Drosophila melanogaster diaphanous gene; mutated alleles of this gene affect spermatogenesis or oogenesis and lead to sterility. The protein (DIA) encoded by the human gene (DIA) is the first human member of the growing FH1/FH2 protein family. Members of this protein family affect cytokinesis and other actin-mediated morphogenetic processes that are required in early steps of development. We propose that the human DIA gene is one of the genes responsible for POF and that it affects the cell divisions that lead to ovarian follicle formation.
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Affiliation(s)
- S Bione
- Institute of Genetics, Biochemistry and Evolution, Consiglio Nationale delle Ricerche, University of Pavia, Pavia, Italy
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48
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Lynch ED. Nonsyndromic Deafness DFNA1 Associated with Mutation of a Human Homolog of the Drosophila Gene diaphanous. Science 1997. [DOI: 10.1126/science.278.5341.1315] [Citation(s) in RCA: 304] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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49
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Abstract
Mammalian nephrogenesis constitutes a series of complex developmental processes in which there is a differentiation and rapid proliferation of pluripotent cells leading to the formation of a defined sculpted tissue mass, and this is followed by a continuum of cell replication and terminal differentiation. Metanephrogenesis ensues with the intercalation of epithelial ureteric bud into loosely organized metanephric mesenchyme. Such an interaction is reciprocal, such that the intercalating ureteric bud induces the conversion of metanephric mesenchyme into an epithelial phenotype, while the mesenchyme stimulates the iterations of the ureteric bud. The induced mesenchyme then undergoes a series of developmental stages to form a mature glomerulus and tubular segments of the kidney. Coincidental with the formation of these nephric elements, the developing kidney is vascularized by the process of vasculogenesis and angiogenesis. Thus, the process of metanephric development is quite complex, and it involves a diverse group of molecules who's biological activities are inter-linked with one another and they regulate, in a concerted manner, the differentiation and maturation of the mammalian kidney. This diverse group of molecules include extracellular matrix (ECM) proteins and their receptors, ECM-degrading enzymes and their inhibitors, growth factors and their receptors, proto-oncogenes and transcription factors. A large body of literature data are available, which suggest a critical role of these molecules in metanephric development, and this review summarizes the recent developments that relate to metanephrogenesis.
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Affiliation(s)
- E I Wallner
- Department of Medicine, Northwestern University Medical School, Chicago, Illinois 60611, USA
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50
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Kanwar YS, Carone FA, Kumar A, Wada J, Ota K, Wallner EI. Role of extracellular matrix, growth factors and proto-oncogenes in metanephric development. Kidney Int 1997; 52:589-606. [PMID: 9291177 DOI: 10.1038/ki.1997.372] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Y S Kanwar
- Department of Pathology, Northwestern University Medical School, Chicago, Illinois 60611, USA
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