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Kessler S, Minoux M, Joshi O, Ben Zouari Y, Ducret S, Ross F, Vilain N, Salvi A, Wolff J, Kohler H, Stadler MB, Rijli FM. A multiple super-enhancer region establishes inter-TAD interactions and controls Hoxa function in cranial neural crest. Nat Commun 2023; 14:3242. [PMID: 37277355 DOI: 10.1038/s41467-023-38953-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 05/19/2023] [Indexed: 06/07/2023] Open
Abstract
Enhancer-promoter interactions preferentially occur within boundary-insulated topologically associating domains (TADs), limiting inter-TAD interactions. Enhancer clusters in linear proximity, termed super-enhancers (SEs), ensure high target gene expression levels. Little is known about SE topological regulatory impact during craniofacial development. Here, we identify 2232 genome-wide putative SEs in mouse cranial neural crest cells (CNCCs), 147 of which target genes establishing CNCC positional identity during face formation. In second pharyngeal arch (PA2) CNCCs, a multiple SE-containing region, partitioned into Hoxa Inter-TAD Regulatory Element 1 and 2 (HIRE1 and HIRE2), establishes long-range inter-TAD interactions selectively with Hoxa2, that is required for external and middle ear structures. HIRE2 deletion in a Hoxa2 haploinsufficient background results in microtia. HIRE1 deletion phenocopies the full homeotic Hoxa2 knockout phenotype and induces PA3 and PA4 CNCC abnormalities correlating with Hoxa2 and Hoxa3 transcriptional downregulation. Thus, SEs can overcome TAD insulation and regulate anterior Hoxa gene collinear expression in a CNCC subpopulation-specific manner during craniofacial development.
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Affiliation(s)
- Sandra Kessler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Maryline Minoux
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
- INSERM UMR 1121, Université de Strasbourg, Faculté de Chirurgie Dentaire, 8, rue Sainte Elisabeth, 67 000, Strasbourg, France
| | - Onkar Joshi
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Yousra Ben Zouari
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Sebastien Ducret
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Fiona Ross
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nathalie Vilain
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Adwait Salvi
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Joachim Wolff
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Hubertus Kohler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Michael B Stadler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland
| | - Filippo M Rijli
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
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2
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Maheshwari U, Kraus D, Vilain N, Holwerda SJB, Cankovic V, Maiorano NA, Kohler H, Satoh D, Sigrist M, Arber S, Kratochwil CF, Di Meglio T, Ducret S, Rijli FM. Postmitotic Hoxa5 Expression Specifies Pontine Neuron Positional Identity and Input Connectivity of Cortical Afferent Subsets. Cell Rep 2021; 31:107767. [PMID: 32553152 DOI: 10.1016/j.celrep.2020.107767] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 03/18/2020] [Accepted: 05/21/2020] [Indexed: 12/20/2022] Open
Abstract
The mammalian precerebellar pontine nucleus (PN) has a main role in relaying cortical information to the cerebellum. The molecular determinants establishing ordered connectivity patterns between cortical afferents and precerebellar neurons are largely unknown. We show that expression of Hox5 transcription factors is induced in specific subsets of postmitotic PN neurons at migration onset. Hox5 induction is achieved by response to retinoic acid signaling, resulting in Jmjd3-dependent derepression of Polycomb chromatin and 3D conformational changes. Hoxa5 drives neurons to settle posteriorly in the PN, where they are monosynaptically targeted by cortical neuron subsets mainly carrying limb somatosensation. Furthermore, Hoxa5 postmigratory ectopic expression in PN neurons is sufficient to attract cortical somatosensory inputs regardless of position and avoid visual afferents. Transcriptome analysis further suggests that Hoxa5 is involved in circuit formation. Thus, Hoxa5 coordinates postmitotic specification, migration, settling position, and sub-circuit assembly of PN neuron subsets in the cortico-cerebellar pathway.
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Affiliation(s)
- Upasana Maheshwari
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, 4051 Basel, Switzerland
| | - Dominik Kraus
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, 4051 Basel, Switzerland
| | - Nathalie Vilain
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Sjoerd J B Holwerda
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Vanja Cankovic
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Nicola A Maiorano
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Hubertus Kohler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Daisuke Satoh
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; Biozentrum, University of Basel, Kingelbergstrasse 70, 4056 Basel, Switzerland
| | - Markus Sigrist
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; Biozentrum, University of Basel, Kingelbergstrasse 70, 4056 Basel, Switzerland
| | - Silvia Arber
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; Biozentrum, University of Basel, Kingelbergstrasse 70, 4056 Basel, Switzerland
| | - Claudius F Kratochwil
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Thomas Di Meglio
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Sebastien Ducret
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Filippo M Rijli
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, 4051 Basel, Switzerland.
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3
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Cantù C, Felker A, Zimmerli D, Prummel KD, Cabello EM, Chiavacci E, Méndez-Acevedo KM, Kirchgeorg L, Burger S, Ripoll J, Valenta T, Hausmann G, Vilain N, Aguet M, Burger A, Panáková D, Basler K, Mosimann C. Mutations in Bcl9 and Pygo genes cause congenital heart defects by tissue-specific perturbation of Wnt/β-catenin signaling. Genes Dev 2018; 32:1443-1458. [PMID: 30366904 PMCID: PMC6217730 DOI: 10.1101/gad.315531.118] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/22/2018] [Indexed: 12/31/2022]
Abstract
Bcl9 and Pygopus (Pygo) are obligate Wnt/β-catenin cofactors in Drosophila, yet their contribution to Wnt signaling during vertebrate development remains unresolved. Combining zebrafish and mouse genetics, we document a conserved, β-catenin-associated function for BCL9 and Pygo proteins during vertebrate heart development. Disrupting the β-catenin-BCL9-Pygo complex results in a broadly maintained canonical Wnt response yet perturbs heart development and proper expression of key cardiac regulators. Our work highlights BCL9 and Pygo as selective β-catenin cofactors in a subset of canonical Wnt responses during vertebrate development. Moreover, our results implicate alterations in BCL9 and BCL9L in human congenital heart defects.
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Affiliation(s)
- Claudio Cantù
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Anastasia Felker
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Dario Zimmerli
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Karin D Prummel
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Elena M Cabello
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Elena Chiavacci
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Kevin M Méndez-Acevedo
- Electrochemical Signaling in Development and Disease, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin-Buch, Germany
| | - Lucia Kirchgeorg
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Sibylle Burger
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Jorge Ripoll
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, 28911 Madrid, Spain
| | - Tomas Valenta
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - George Hausmann
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Nathalie Vilain
- Swiss Institute for Experimental Cancer Research (ISREC), École Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, 1015 Lausanne, Switzerland
| | - Michel Aguet
- Swiss Institute for Experimental Cancer Research (ISREC), École Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, 1015 Lausanne, Switzerland
| | - Alexa Burger
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Daniela Panáková
- Electrochemical Signaling in Development and Disease, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin-Buch, Germany
- Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK), partner site Berlin, 10115 Berlin, Germany
| | - Konrad Basler
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
| | - Christian Mosimann
- Institute of Molecular Life Sciences, University of Zürich, 8057 Zürich, Switzerland
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4
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Bechara A, Laumonnerie C, Vilain N, Kratochwil CF, Cankovic V, Maiorano NA, Kirschmann MA, Ducret S, Rijli FM. Hoxa2 Selects Barrelette Neuron Identity and Connectivity in the Mouse Somatosensory Brainstem. Cell Rep 2015; 13:783-797. [PMID: 26489473 DOI: 10.1016/j.celrep.2015.09.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/19/2015] [Accepted: 09/09/2015] [Indexed: 10/22/2022] Open
Abstract
Mouse whiskers are somatotopically mapped in brainstem trigeminal nuclei as neuronal modules known as barrelettes. Whisker-related afferents form barrelettes in ventral principal sensory (vPrV) nucleus, whereas mandibular input targets dorsal PrV (dPrV). How barrelette neuron identity and circuitry is established is poorly understood. We found that ectopic Hoxa2 expression in dPrV neurons is sufficient to attract whisker-related afferents, induce asymmetrical dendrite arbors, and allow ectopic barrelette map formation. Moreover, the thalamic area forming whisker-related barreloids is prenatally targeted by both vPrV and dPrV axons followed by perinatal large-scale pruning of dPrV axons and refinement of vPrV barrelette input. Ectopic Hoxa2 expression allows topographically directed targeting and refinement of dPrV axons with vPrV axons into a single whisker-related barreloid map. Thus, a single HOX transcription factor is sufficient to switch dPrV into a vPrV barrelette neuron program and coordinate input-output topographic connectivity of a dermatome-specific circuit module.
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Affiliation(s)
- Ahmad Bechara
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Christophe Laumonnerie
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Nathalie Vilain
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Claudius F Kratochwil
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Vanja Cankovic
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Nicola A Maiorano
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Moritz A Kirschmann
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Sebastien Ducret
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Filippo M Rijli
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, 4056 Basel, Switzerland.
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5
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Laumonnerie C, Bechara A, Vilain N, Kurihara Y, Kurihara H, Rijli FM. Facial whisker pattern is not sufficient to instruct a whisker-related topographic map in the mouse somatosensory brainstem. Development 2015; 142:3704-12. [PMID: 26417040 DOI: 10.1242/dev.128736] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/15/2015] [Indexed: 11/20/2022]
Abstract
Facial somatosensory input is relayed by trigeminal ganglion (TG) neurons and serially wired to brainstem, thalamus and cortex. Spatially ordered sets of target neurons generate central topographic maps reproducing the spatial arrangement of peripheral facial receptors. Facial pattern provides a necessary template for map formation, but may be insufficient to impose a brain somatotopic pattern. In mice, lower jaw sensory information is relayed by the trigeminal nerve mandibular branch, whose axons target the brainstem dorsal principal sensory trigeminal nucleus (dPrV). Input from mystacial whiskers is relayed by the maxillary branch and forms a topographic representation of rows and whiskers in the ventral PrV (vPrV). To investigate peripheral organisation in imposing a brain topographic pattern, we analysed Edn1(-/-) mice, which present ectopic whisker rows on the lower jaw. We found that these whiskers were innervated by mandibular TG neurons which initially targeted dPrV. Unlike maxillary TG neurons, the ectopic whisker-innervating mandibular neuron cell bodies and pre-target central axons did not segregate into a row-specific pattern nor target the dPrV with a topographic pattern. Following periphery-driven molecular repatterning to a maxillary-like identity, mandibular neurons partially redirected their central projections from dPrV to vPrV. Thus, while able to induce maxillary-like molecular features resulting in vPrV final targeting, a spatially ordered lower jaw ectopic whisker pattern is insufficient to impose row-specific pre-target organisation of the central mandibular tract or a whisker-related matching pattern of afferents in dPrV. These results provide novel insights into periphery-dependent versus periphery-independent mechanisms of trigeminal ganglion and brainstem patterning in matching whisker topography.
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Affiliation(s)
- Christophe Laumonnerie
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Ahmad Bechara
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Nathalie Vilain
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Yukiko Kurihara
- Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0075, Japan
| | - Hiroki Kurihara
- Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, 102-0075, Japan
| | - Filippo M Rijli
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland University of Basel, Basel 4056, Switzerland
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6
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Minoux M, Kratochwil CF, Ducret S, Amin S, Kitazawa T, Kurihara H, Bobola N, Vilain N, Rijli FM. Mouse Hoxa2 mutations provide a model for microtia and auricle duplication. Development 2013; 140:4386-97. [DOI: 10.1242/dev.098046] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
External ear abnormalities are frequent in newborns ranging from microtia to partial auricle duplication. Little is known about the molecular mechanisms orchestrating external ear morphogenesis. In humans, HOXA2 partial loss of function induces a bilateral microtia associated with an abnormal shape of the auricle. In mice, Hoxa2 inactivation at early gestational stages results in external auditory canal (EAC) duplication and absence of the auricle, whereas its late inactivation results in a hypomorphic auricle, mimicking the human HOXA2 mutant condition. By genetic fate mapping we found that the mouse auricle (or pinna) derives from the Hoxa2-expressing neural crest-derived mesenchyme of the second pharyngeal arch, and not from a composite of first and second arch mesenchyme as previously proposed based on morphological observation of human embryos. Moreover, the mouse EAC is entirely lined by Hoxa2-negative first arch mesenchyme and does not develop at the first pharyngeal cleft, as previously assumed. Conditional ectopic Hoxa2 expression in first arch neural crest is sufficient to induce a complete duplication of the pinna and a loss of the EAC, suggesting transformation of the first arch neural crest-derived mesenchyme lining the EAC into an ectopic pinna. Hoxa2 partly controls the morphogenesis of the pinna through the BMP signalling pathway and expression of Eya1, which in humans is involved in branchio-oto-renal syndrome. Thus, Hoxa2 loss- and gain-of-function approaches in mice provide a suitable model to investigate the molecular aetiology of microtia and auricle duplication.
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Affiliation(s)
- Maryline Minoux
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
- INSERM UMR 1121, Université de Strasbourg, Faculté de Chirurgie Dentaire, 1, place de l’hôpital, 67 000 Strasbourg, France
| | - Claudius F. Kratochwil
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
- University of Basel, CH-4056 Basel, Switzerland
| | - Sébastien Ducret
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Shilu Amin
- School of Dentistry, Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Taro Kitazawa
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroki Kurihara
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nicoletta Bobola
- School of Dentistry, Faculty of Medical and Human Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Nathalie Vilain
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Filippo M. Rijli
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
- University of Basel, CH-4056 Basel, Switzerland
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7
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Cantù C, Valenta T, Hausmann G, Vilain N, Aguet M, Basler K. The Pygo2-H3K4me2/3 interaction is dispensable for mouse development and Wnt signaling-dependent transcription. Development 2013; 140:2377-86. [PMID: 23637336 DOI: 10.1242/dev.093591] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Pygopus has been discovered as a fundamental Wnt signaling component in Drosophila. The mouse genome encodes two Pygopus homologs, Pygo1 and Pygo2. They serve as context-dependent β-catenin coactivators, with Pygo2 playing the more important role. All Pygo proteins share a highly conserved plant homology domain (PHD) that allows them to bind di- and trimethylated lysine 4 of histone H3 (H3K4me2/3). Despite the structural conservation of this domain, the relevance of histone binding for the role of Pygo2 as a Wnt signaling component and as a reader of chromatin modifications remains speculative. Here we generate a knock-in mouse line, homozygous for a Pygo2 mutant defective in chromatin binding. We show that even in the absence of the potentially redundant Pygo1, Pygo2 does not require the H3K4me2/3 binding activity to sustain its function during mouse development. Indeed, during tissue homeostasis, Wnt/β-catenin-dependent transcription is largely unaffected. However, the Pygo2-chromatin interaction is relevant in testes, where, importantly, Pygo2 binds in vivo to the chromatin in a PHD-dependent manner. Its presence on regulatory regions does not affect the transcription of nearby genes; rather, it is important for the recruitment of the histone acetyltransferase Gcn5 to chromatin, consistent with a testis-specific and Wnt-unrelated role for Pygo2 as a chromatin remodeler.
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Affiliation(s)
- Claudio Cantù
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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8
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Di Meglio T, Kratochwil CF, Vilain N, Loche A, Vitobello A, Yonehara K, Hrycaj SM, Roska B, Peters AHFM, Eichmann A, Wellik D, Ducret S, Rijli FM. Ezh2 orchestrates topographic migration and connectivity of mouse precerebellar neurons. Science 2013; 339:204-7. [PMID: 23307742 DOI: 10.1126/science.1229326] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We investigated the role of histone methyltransferase Ezh2 in tangential migration of mouse precerebellar pontine nuclei, the main relay between neocortex and cerebellum. By counteracting the sonic hedgehog pathway, Ezh2 represses Netrin1 in dorsal hindbrain, which allows normal pontine neuron migration. In Ezh2 mutants, ectopic Netrin1 derepression results in abnormal migration and supernumerary nuclei integrating in brain circuitry. Moreover, intrinsic topographic organization of pontine nuclei according to rostrocaudal progenitor origin is maintained throughout migration and correlates with patterned cortical input. Ezh2 maintains spatially restricted Hox expression, which, in turn, regulates differential expression of the repulsive receptor Unc5b in migrating neurons; together, they generate subsets with distinct responsiveness to environmental Netrin1. Thus, Ezh2-dependent epigenetic regulation of intrinsic and extrinsic transcriptional programs controls topographic neuronal guidance and connectivity in the cortico-ponto-cerebellar pathway.
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Affiliation(s)
- Thomas Di Meglio
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
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9
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Vitobello A, Ferretti E, Lampe X, Vilain N, Ducret S, Ori M, Spetz JF, Selleri L, Rijli FM. Hox and Pbx factors control retinoic acid synthesis during hindbrain segmentation. Dev Cell 2011; 20:469-82. [PMID: 21497760 DOI: 10.1016/j.devcel.2011.03.011] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 02/07/2011] [Accepted: 03/16/2011] [Indexed: 12/11/2022]
Abstract
In vertebrate embryos, retinoic acid (RA) synthesized in the mesoderm by Raldh2 emanates to the hindbrain neuroepithelium, where it induces anteroposterior (AP)-restricted Hox expression patterns and rhombomere segmentation. However, how appropriate spatiotemporal RA activity is generated in the hindbrain is poorly understood. By analyzing Pbx1/Pbx2 and Hoxa1/Pbx1 null mice, we found that Raldh2 is itself under the transcriptional control of these factors and that the resulting RA-deficient phenotypes can be partially rescued by exogenous RA. Hoxa1-Pbx1/2-Meis2 directly binds a specific regulatory element that is required to maintain normal Raldh2 expression levels in vivo. Mesoderm-specific Xhoxa1 and Xpbx1b knockdowns in Xenopus embryos also result in Xraldh2 downregulation and hindbrain defects similar to mouse mutants, demonstrating conservation of this Hox-Pbx-dependent regulatory pathway. These findings reveal a feed-forward mechanism linking Hox-Pbx-dependent RA synthesis during early axial patterning with the establishment of spatially restricted Hox-Pbx activity in the developing hindbrain.
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Affiliation(s)
- Antonio Vitobello
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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10
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Deka J, Wiedemann N, Anderle P, Murphy-Seiler F, Bultinck J, Eyckerman S, Stehle JC, André S, Vilain N, Zilian O, Robine S, Delorenzi M, Basler K, Aguet M. Bcl9/Bcl9l Are Critical for Wnt-Mediated Regulation of Stem Cell Traits in Colon Epithelium and Adenocarcinomas. Cancer Res 2010; 70:6619-28. [DOI: 10.1158/0008-5472.can-10-0148] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Wilson A, Ardiet DL, Saner C, Vilain N, Beermann F, Aguet M, Macdonald HR, Zilian O. Normal Hemopoiesis and Lymphopoiesis in the Combined Absence of Numb and Numblike. J Immunol 2007; 178:6746-51. [PMID: 17513721 DOI: 10.4049/jimmunol.178.11.6746] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mammalian ortholog of the conserved Drosophila adaptor protein Numb (Nb) and its homolog Numblike (Nbl) modulate neuronal cell fate determination at least in part by antagonizing Notch signaling. Because the Notch pathway has been implicated in regulating hemopoietic stem cell self-renewal and T cell fate specification in mammals, we investigated the role of Nb and Nbl in hemopoiesis using conditional gene targeting. Surprisingly simultaneous deletion of both Nb and Nbl in murine bone marrow precursors did not affect the ability of stem cells to self-renew or to give rise to differentiated myeloid or lymphoid progeny, even under competitive conditions in mixed chimeras. Furthermore, T cell fate specification and intrathymic T cell development were unaffected in the combined absence of Nb and Nbl. Collectively our data indicate that the Nb family of adaptor proteins is dispensable for hemopoiesis and lymphopoiesis in mice, despite their proposed role in neuronal stem cell development.
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Affiliation(s)
- Anne Wilson
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Switzerland
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van Bezooijen RL, Deruiter MC, Vilain N, Monteiro RM, Visser A, van der Wee-Pals L, van Munsteren CJ, Hogendoorn PCW, Aguet M, Mummery CL, Papapoulos SE, Ten Dijke P, Löwik CWGM. SOST expression is restricted to the great arteries during embryonic and neonatal cardiovascular development. Dev Dyn 2007; 236:606-12. [PMID: 17195180 DOI: 10.1002/dvdy.21054] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Spatial-temporal regulation of bone morphogenetic protein (BMP) and Wnt activity is essential for normal cardiovascular development, and altered activity of these growth factors causes maldevelopment of the cardiac outflow tract and great arteries. In the present study, we show that SOST, a Dan family member reported to antagonize BMP and Wnt activity, is expressed within the medial vessel wall of the great arteries containing smooth muscle cells. The ascending aorta, aortic arch, brachiocephalic artery, common carotids, and pulmonary trunk were all associated with SOST expressing smooth muscle cells, while the heart itself, including the valves, and more distal arteries, that is, pulmonary arteries, subclavian arteries, and descending aorta, were negative. SOST was expressed from embryonic day 15.5 up to the neonatal period. SOST expression, however, did not correspond with inhibition of Smad-dependent BMP activity or beta-catenin-dependent Wnt activity in the great arteries. Activity of both signaling pathways was already down-regulated before induction of SOST expression.
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Affiliation(s)
- Rutger L van Bezooijen
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands.
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Vilain N, Tsai-Pflugfelder M, Benoit A, Gasser SM, Leroy D. Modulation of drug sensitivity in yeast cells by the ATP-binding domain of human DNA topoisomerase IIalpha. Nucleic Acids Res 2003; 31:5714-22. [PMID: 14500835 PMCID: PMC206448 DOI: 10.1093/nar/gkg737] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Epipodophyllotoxins are effective antitumour drugs that trap eukaryotic DNA topoisomerase II in a covalent complex with DNA. Based on DNA cleavage assays, the mode of interaction of these drugs was proposed to involve amino acid residues of the catalytic site. An in vitro binding study, however, revealed two potential binding sites for etoposide within human DNA topoisomerase IIalpha (htopoIIalpha), one in the catalytic core of the enzyme and one in the ATP-binding N-terminal domain. Here we have tested how N-terminal mutations that reduce the affinity of the site for etoposide or ATP affect the sensitivity of yeast cells to etoposide. Surprisingly, when introduced into full-length enzymes, mutations that lower the drug binding capacity of the N-terminal domain in vitro render yeast more sensitive to epipodophyllotoxins. Consistently, when the htopoIIalpha N-terminal domain alone is overexpressed in the presence of yeast topoII, cells become more resistant to etoposide. Point mutations that weaken etoposide binding eliminate this resistance phenotype. We argue that the N-terminal ATP-binding pocket competes with the active site of the holoenzyme for binding etoposide both in cis and in trans with different outcomes, suggesting that each topoisomerase II monomer has two non-equivalent drug-binding sites.
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Affiliation(s)
- Nathalie Vilain
- Swiss Institute for Experimental Cancer Research, Ch. des Boveresses 155, CH-1066 Epalinges s/Lausanne, Switzerland
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