1
|
Nowak B, Kozlowska E, Pawlik W, Fiszer A. Atrophin-1 Function and Dysfunction in Dentatorubral-Pallidoluysian Atrophy. Mov Disord 2023; 38:526-536. [PMID: 36809552 DOI: 10.1002/mds.29355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 01/19/2023] [Accepted: 01/31/2023] [Indexed: 02/23/2023] Open
Abstract
Dentatorubral-pallidoluysian atrophy (DRPLA) is a rare, incurable genetic disease that belongs to the group of polyglutamine (polyQ) diseases. DRPLA is the most common in the Japanese population; however, its global prevalence is also increasing due to better clinical recognition. It is characterized by cerebellar ataxia, myoclonus, epilepsy, dementia, and chorea. DRPLA is caused by dynamic mutation of CAG repeat expansion in ATN1 gene encoding the atrophin-1 protein. In the cascade of molecular disturbances, the pathological form of atrophin-1 is the initial factor, which has not been precisely characterized so far. Reports indicate that DRPLA is associated with disrupted protein-protein interactions (in which an expanded polyQ tract plays a crucial role), as well as gene expression deregulation. There is a great need to design efficient therapy that would address the underlying neurodegenerative process and thus prevent or alleviate DRPLA symptoms. An in-depth understanding of the normal atrophin-1 function and mutant atrophin-1 dysfunction is crucial for this purpose. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Bartosz Nowak
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Emilia Kozlowska
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Weronika Pawlik
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Agnieszka Fiszer
- Department of Medical Biotechnology, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| |
Collapse
|
2
|
A Case of Congenital Hypotonia and Developmental Delay in an Individual with a De Novo Variant Outside of the Canonical HX-Motif of ATN1. Case Rep Genet 2023; 2023:1581876. [PMID: 36660549 PMCID: PMC9845047 DOI: 10.1155/2023/1581876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/09/2022] [Accepted: 12/15/2022] [Indexed: 01/11/2023] Open
Abstract
We present a case of a 4-year-old female with a de novo heterozygous variant in the ATN1 gene. The whole exome sequencing was performed on the patient and her parents, and a likely pathogenic, de novo variant was identified in exon 5 of the ATN1 gene. There are two well-documented conditions associated with the ATN1 gene: congenital hypotonia, epilepsy, developmental delay, and digital anomalies (CHEDDA) syndrome and dentatorubral-pallidoluysian atrophy (DRPLA). Unlike DRPLA which is caused by an expanded trinucleotide repeat, CHEDDA syndrome is caused by variants in the histidine-rich (HX) motif at exon 7 of ATN1 similar to the de novo variant found in exon 5 of the presented individual. CHEDDA syndrome is a neurodevelopmental disorder previously documented in over 17 unrelated individuals. Compared to other documented CHEDDA syndrome cases, this individual shares similarities in respect to hypotonia, hearing impairment, impaired gross and fine motor ability, gastrointestinal abnormalities, hyperextensible joints, and frontal bossing. However, the individual presented here has only a moderate developmental delay and has acquired more developmental milestones such as higher-level language skills and more developed fine motor skills, than previously described individuals. The authors of this paper believe the patient's milder phenotype may be due to the variant's location outside of the canonic HX motif.
Collapse
|
3
|
Kim H, Gomez-Pastor R. HSF1 and Its Role in Huntington's Disease Pathology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1410:35-95. [PMID: 36396925 DOI: 10.1007/5584_2022_742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE OF REVIEW Heat shock factor 1 (HSF1) is the master transcriptional regulator of the heat shock response (HSR) in mammalian cells and is a critical element in maintaining protein homeostasis. HSF1 functions at the center of many physiological processes like embryogenesis, metabolism, immune response, aging, cancer, and neurodegeneration. However, the mechanisms that allow HSF1 to control these different biological and pathophysiological processes are not fully understood. This review focuses on Huntington's disease (HD), a neurodegenerative disease characterized by severe protein aggregation of the huntingtin (HTT) protein. The aggregation of HTT, in turn, leads to a halt in the function of HSF1. Understanding the pathways that regulate HSF1 in different contexts like HD may hold the key to understanding the pathomechanisms underlying other proteinopathies. We provide the most current information on HSF1 structure, function, and regulation, emphasizing HD, and discussing its potential as a biological target for therapy. DATA SOURCES We performed PubMed search to find established and recent reports in HSF1, heat shock proteins (Hsp), HD, Hsp inhibitors, HSF1 activators, and HSF1 in aging, inflammation, cancer, brain development, mitochondria, synaptic plasticity, polyglutamine (polyQ) diseases, and HD. STUDY SELECTIONS Research and review articles that described the mechanisms of action of HSF1 were selected based on terms used in PubMed search. RESULTS HSF1 plays a crucial role in the progression of HD and other protein-misfolding related neurodegenerative diseases. Different animal models of HD, as well as postmortem brains of patients with HD, reveal a connection between the levels of HSF1 and HSF1 dysfunction to mutant HTT (mHTT)-induced toxicity and protein aggregation, dysregulation of the ubiquitin-proteasome system (UPS), oxidative stress, mitochondrial dysfunction, and disruption of the structural and functional integrity of synaptic connections, which eventually leads to neuronal loss. These features are shared with other neurodegenerative diseases (NDs). Currently, several inhibitors against negative regulators of HSF1, as well as HSF1 activators, are developed and hold promise to prevent neurodegeneration in HD and other NDs. CONCLUSION Understanding the role of HSF1 during protein aggregation and neurodegeneration in HD may help to develop therapeutic strategies that could be effective across different NDs.
Collapse
Affiliation(s)
- Hyuck Kim
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Rocio Gomez-Pastor
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN, USA.
| |
Collapse
|
4
|
Johnson SL, Tsou WL, Prifti MV, Harris AL, Todi SV. A survey of protein interactions and posttranslational modifications that influence the polyglutamine diseases. Front Mol Neurosci 2022; 15:974167. [PMID: 36187346 PMCID: PMC9515312 DOI: 10.3389/fnmol.2022.974167] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/27/2022] [Indexed: 01/20/2023] Open
Abstract
The presence and aggregation of misfolded proteins has deleterious effects in the nervous system. Among the various diseases caused by misfolded proteins is the family of the polyglutamine (polyQ) disorders. This family comprises nine members, all stemming from the same mutation—the abnormal elongation of a polyQ repeat in nine different proteins—which causes protein misfolding and aggregation, cellular dysfunction and disease. While it is the same type of mutation that causes them, each disease is distinct: it is influenced by regions and domains that surround the polyQ repeat; by proteins with which they interact; and by posttranslational modifications they receive. Here, we overview the role of non-polyQ regions that control the pathogenicity of the expanded polyQ repeat. We begin by introducing each polyQ disease, the genes affected, and the symptoms experienced by patients. Subsequently, we provide a survey of protein-protein interactions and posttranslational modifications that regulate polyQ toxicity. We conclude by discussing shared processes and pathways that bring some of the polyQ diseases together and may serve as common therapeutic entry points for this family of incurable disorders.
Collapse
Affiliation(s)
- Sean L. Johnson
- Department of Pharmacology, Wayne State University, Detroit, MI, United States
| | - Wei-Ling Tsou
- Department of Pharmacology, Wayne State University, Detroit, MI, United States
| | - Matthew V. Prifti
- Department of Pharmacology, Wayne State University, Detroit, MI, United States
| | - Autumn L. Harris
- Department of Pharmacology, Wayne State University, Detroit, MI, United States
- Maximizing Access to Research Careers (MARC) Program, Wayne State University, Detroit, MI, United States
| | - Sokol V. Todi
- Department of Pharmacology, Wayne State University, Detroit, MI, United States
- Maximizing Access to Research Careers (MARC) Program, Wayne State University, Detroit, MI, United States
- Department of Neurology, Wayne State University, Detroit, MI, United States
- *Correspondence: Sokol V. Todi,
| |
Collapse
|
5
|
Strutt H, Strutt D. How do the Fat-Dachsous and core planar polarity pathways act together and independently to coordinate polarized cell behaviours? Open Biol 2021; 11:200356. [PMID: 33561385 PMCID: PMC8061702 DOI: 10.1098/rsob.200356] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Planar polarity describes the coordinated polarization of cells within the plane of a tissue. This is controlled by two main pathways in Drosophila: the Frizzled-dependent core planar polarity pathway and the Fat–Dachsous pathway. Components of both of these pathways become asymmetrically localized within cells in response to long-range upstream cues, and form intercellular complexes that link polarity between neighbouring cells. This review examines if and when the two pathways are coupled, focusing on the Drosophila wing, eye and abdomen. There is strong evidence that the pathways are molecularly coupled in tissues that express a specific isoform of the core protein Prickle, namely Spiny-legs. However, in other contexts, the linkages between the pathways are indirect. We discuss how the two pathways act together and independently to mediate a diverse range of effects on polarization of cell structures and behaviours.
Collapse
Affiliation(s)
- Helen Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - David Strutt
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| |
Collapse
|
6
|
Das P, Bhadra MP. Histone deacetylase (Rpd3) regulates Drosophila early brain development via regulation of Tailless. Open Biol 2020; 10:200029. [PMID: 32873153 PMCID: PMC7536075 DOI: 10.1098/rsob.200029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 07/29/2020] [Indexed: 11/29/2022] Open
Abstract
Tailless is a committed transcriptional repressor and principal regulator of the brain and eye development in Drosophila. Rpd3, the histone deacetylase, is an established repressor that interacts with co-repressors like Sin3a, Prospero, Brakeless and Atrophin. This study aims at deciphering the role of Rpd3 in embryonic segmentation and larval brain development in Drosophila. It delineates the mechanism of Tailless regulation by Rpd3, along with its interacting partners. There was a significant reduction in Tailless in Rpd3 heteroallelic mutant embryos, substantiating that Rpd3 is indispensable for the normal Tailless expression. The expression of the primary readout, Tailless was correlative to the expression of the neural cell adhesion molecule homologue, Fascilin2 (Fas2). Rpd3 also aids in the proper development of the mushroom body. Both Tailless and Fas2 expression are reported to be antagonistic to the epidermal growth factor receptor (EGFR) expression. The decrease in Tailless and Fas2 expression highlights that EGFR is upregulated in the larval mutants, hindering brain development. This study outlines the axis comprising Rpd3, dEGFR, Tailless and Fas2, which interact to fine-tune the early segmentation and larval brain development. Therefore, Rpd3 along with Tailless has immense significance in early embryogenesis and development of the larval brain.
Collapse
Affiliation(s)
- Paromita Das
- Applied Biology Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500 007, India
- Academy of Scientific and Innovative Research (AcSIR) Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai 600 113, India
| | - Manika Pal Bhadra
- Applied Biology Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500 007, India
- Academy of Scientific and Innovative Research (AcSIR) Training and Development Complex, CSIR Campus, CSIR Road, Taramani, Chennai 600 113, India
| |
Collapse
|
7
|
Hyde CJ, Fitzgibbon QP, Elizur A, Smith GG, Ventura T. Transcriptional profiling of spiny lobster metamorphosis reveals three new additions to the nuclear receptor superfamily. BMC Genomics 2019; 20:531. [PMID: 31253104 PMCID: PMC6599367 DOI: 10.1186/s12864-019-5925-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 06/23/2019] [Indexed: 12/19/2022] Open
Abstract
Background The Crustacea are an evolutionarily diverse taxon which underpins marine food webs and contributes significantly to the global economy. However, our knowledge of crustacean endocrinology and development is far behind that of terrestrial arthropods. Here we present a unique insight into the molecular pathways coordinating crustacean metamorphosis, by reconciling nuclear receptor (NR) gene activity from a 12-stage, 3-replicate transcriptome in the ornate spiny lobster (Panulirus ornatus) during larval development. Results We annotated 18 distinct nuclear receptor genes, including three novel NRs which are upregulated prior to metamorphosis and have hence been named the “molt-associated receptors” (MARs). We also demonstrate the ecdysone-responsive expression of several known molt-related NRs including ecdysone receptor, fushi-tarazu-F1 and E75. Phylogenetic analysis of the curated NR family confirmed gene annotations and suggested that the MARs are a recent addition to the crustacean superfamily, occurring across the Malacostraca from the Stomatopoda to the Decapoda. The ligand-binding domain of these receptors appears to be less conserved than that of typical group-1 NRs. Expression data from two other crustacean species was utilized to examine MAR expression. The Y-organ of the tropical land crab showed a decline in expression of all MARs from intermolt to post-molt. Tissue distributions showed gonad-enriched expression in the Eastern rock lobster and antennal gland-enriched expression in the tropical land crab, although expression was evident across most tissues. Conclusion By mining transcriptome data, we have curated an extensive list of NR genes expressed during the metamorphic molts of P. ornatus, including three novel crustacean NRs which appear to play a role in the molting process. Divergence of the E-region of these new receptors indicates that they may have adopted a function that is unconventional for NRs. Based on expression patterns, we can confirm that a number of NRs play a role in the ecdysone cassette which regulates molting in crustaceans. This study describes in detail the molecular events surrounding crustacean molting and metamorphosis by taking advantage of the distinctive life history unique to achelatan crustaceans. Electronic supplementary material The online version of this article (10.1186/s12864-019-5925-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Cameron J Hyde
- Genecology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, 4556, Australia
| | - Quinn P Fitzgibbon
- Institute for Marine & Antarctic Studies (IMAS), University of Tasmania, Private Bag 49, Hobart, TAS, 7001, Australia
| | - Abigail Elizur
- Genecology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, 4556, Australia
| | - Gregory G Smith
- Institute for Marine & Antarctic Studies (IMAS), University of Tasmania, Private Bag 49, Hobart, TAS, 7001, Australia
| | - Tomer Ventura
- Genecology Research Centre, University of the Sunshine Coast, Sippy Downs, Queensland, 4556, Australia.
| |
Collapse
|
8
|
Vangelisti A, Zambrano LS, Caruso G, Macheda D, Bernardi R, Usai G, Mascagni F, Giordani T, Gucci R, Cavallini A, Natali L. How an ancient, salt-tolerant fruit crop, Ficus carica L., copes with salinity: a transcriptome analysis. Sci Rep 2019; 9:2561. [PMID: 30796285 PMCID: PMC6385202 DOI: 10.1038/s41598-019-39114-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 01/17/2019] [Indexed: 12/20/2022] Open
Abstract
Although Ficus carica L. (fig) is one of the most resistant fruit tree species to salinity, no comprehensive studies are currently available on its molecular responses to salinity. Here we report a transcriptome analysis of F. carica cv. Dottato exposed to 100 mM sodium chloride for 7 weeks, where RNA-seq analysis was performed on leaf samples at 24 and 48 days after the beginning of salinization; a genome-derived fig transcriptome was used as a reference. At day 24, 224 transcripts were significantly up-regulated and 585 were down-regulated, while at day 48, 409 genes were activated and 285 genes were repressed. Relatively small transcriptome changes were observed after 24 days of salt treatment, showing that fig plants initially tolerate salt stress. However, after an early down-regulation of some cell functions, major transcriptome changes were observed after 48 days of salinity. Seven weeks of 100 mM NaCl dramatically changed the repertoire of expressed genes, leading to activation or reactivation of many cell functions. We also identified salt-regulated genes, some of which had not been previously reported to be involved in plant salinity responses. These genes could be potential targets for the selection of favourable genotypes, through breeding or biotechnology, to improve salt tolerance in fig or other crops.
Collapse
Affiliation(s)
- Alberto Vangelisti
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Liceth Solorzano Zambrano
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Giovanni Caruso
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Desiré Macheda
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Rodolfo Bernardi
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Gabriele Usai
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Flavia Mascagni
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Tommaso Giordani
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Riccardo Gucci
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Andrea Cavallini
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy
| | - Lucia Natali
- Department of Agriculture, Food, and Environment, University of Pisa, Via del Borghetto 80, I-56124, Pisa, Italy.
| |
Collapse
|
9
|
Bérubé-Simard FA, Pilon N. Molecular dissection of CHARGE syndrome highlights the vulnerability of neural crest cells to problems with alternative splicing and other transcription-related processes. Transcription 2018; 10:21-28. [PMID: 30205741 DOI: 10.1080/21541264.2018.1521213] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
CHARGE syndrome is characterized by co-occurrence of multiple malformations due to abnormal development of neural crest cells. Here, we review the phenotypic and molecular overlap between CHARGE syndrome and similar pathologies, and further discuss the observation that neural crest cells appear especially sensitive to malfunction of the chromatin-transcription-splicing molecular hub.
Collapse
Affiliation(s)
- Félix-Antoine Bérubé-Simard
- a Laboratoire de génétique moléculaire du développement, Département des sciences biologiques , Université du Québec à Montréal (UQAM) , Montréal , QC , Canada.,b Centre d'Excellence en Recherche sur les Maladies Orphelines - Fondation Courtois (CERMO-FC) , Université du Québec à Montréal (UQAM) , Montréal , QC , Canada
| | - Nicolas Pilon
- a Laboratoire de génétique moléculaire du développement, Département des sciences biologiques , Université du Québec à Montréal (UQAM) , Montréal , QC , Canada.,b Centre d'Excellence en Recherche sur les Maladies Orphelines - Fondation Courtois (CERMO-FC) , Université du Québec à Montréal (UQAM) , Montréal , QC , Canada.,c Département de pédiatrie , Université de Montréal , Montréal , QC , Canada
| |
Collapse
|
10
|
Wang Z, Lyu J, Wang F, Miao C, Nan Z, Zhang J, Xi Y, Zhou Q, Yang X, Ge W. The histone deacetylase HDAC1 positively regulates Notch signaling during Drosophila wing development. Biol Open 2018; 7:bio.029637. [PMID: 29437043 PMCID: PMC5861358 DOI: 10.1242/bio.029637] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The Notch signaling pathway is highly conserved across different animal species and plays crucial roles in development and physiology. Regulation of Notch signaling occurs at multiple levels in different tissues and cell types. Here, we show that the histone deacetylase HDAC1 acts as a positive regulator of Notch signaling during Drosophila wing development. Depletion of HDAC1 causes wing notches on the margin of adult wing. Consistently, the expression of Notch target genes is reduced in the absence of HDAC1 during wing margin formation. We further provide evidence that HDAC1 acts upstream of Notch activation. Mechanistically, we show that HDAC1 regulates Notch protein levels by promoting Notch transcription. Consistent with this, the HDAC1-associated transcriptional co-repressor Atrophin (Atro) is also required for transcriptional activation of Notch in the wing disc. In summary, our results demonstrate that HDAC1 positively regulates Notch signaling and reveal a previously unidentified function of HDAC1 in Notch signaling.
Collapse
Affiliation(s)
- Zehua Wang
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jialan Lyu
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Fang Wang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Chen Miao
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Zi Nan
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jiayu Zhang
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Yongmei Xi
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Qi Zhou
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaohang Yang
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Wanzhong Ge
- Division of Human Reproduction and Developmental Genetics, The Women's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China .,Institute of Genetics and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| |
Collapse
|
11
|
Kacsoh BZ, Greene CS, Bosco G. Machine Learning Analysis Identifies Drosophila Grunge/Atrophin as an Important Learning and Memory Gene Required for Memory Retention and Social Learning. G3 (BETHESDA, MD.) 2017; 7:3705-3718. [PMID: 28889104 PMCID: PMC5677163 DOI: 10.1534/g3.117.300172] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/07/2017] [Indexed: 12/12/2022]
Abstract
High-throughput experiments are becoming increasingly common, and scientists must balance hypothesis-driven experiments with genome-wide data acquisition. We sought to predict novel genes involved in Drosophila learning and long-term memory from existing public high-throughput data. We performed an analysis using PILGRM, which analyzes public gene expression compendia using machine learning. We evaluated the top prediction alongside genes involved in learning and memory in IMP, an interface for functional relationship networks. We identified Grunge/Atrophin (Gug/Atro), a transcriptional repressor, histone deacetylase, as our top candidate. We find, through multiple, distinct assays, that Gug has an active role as a modulator of memory retention in the fly and its function is required in the adult mushroom body. Depletion of Gug specifically in neurons of the adult mushroom body, after cell division and neuronal development is complete, suggests that Gug function is important for memory retention through regulation of neuronal activity, and not by altering neurodevelopment. Our study provides a previously uncharacterized role for Gug as a possible regulator of neuronal plasticity at the interface of memory retention and memory extinction.
Collapse
Affiliation(s)
- Balint Z Kacsoh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
| | - Casey S Greene
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Giovanni Bosco
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
| |
Collapse
|
12
|
Selvan N, Williamson R, Mariappa D, Campbell DG, Gourlay R, Ferenbach AT, Aristotelous T, Hopkins-Navratilova I, Trost M, van Aalten DMF. A mutant O-GlcNAcase enriches Drosophila developmental regulators. Nat Chem Biol 2017; 13:882-887. [PMID: 28604694 DOI: 10.1038/nchembio.2404] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 03/14/2017] [Indexed: 01/09/2023]
Abstract
Protein O-GlcNAcylation is a reversible post-translational modification of serines and threonines on nucleocytoplasmic proteins. It is cycled by the enzymes O-GlcNAc transferase (OGT) and O-GlcNAc hydrolase (O-GlcNAcase or OGA). Genetic approaches in model organisms have revealed that protein O-GlcNAcylation is essential for early embryogenesis. The Drosophila melanogaster gene supersex combs (sxc), which encodes OGT, is a polycomb gene, whose null mutants display homeotic transformations and die at the pharate adult stage. However, the identities of the O-GlcNAcylated proteins involved and the underlying mechanisms linking these phenotypes to embryonic development are poorly understood. Identification of O-GlcNAcylated proteins from biological samples is hampered by the low stoichiometry of this modification and by limited enrichment tools. Using a catalytically inactive bacterial O-GlcNAcase mutant as a substrate trap, we have enriched the O-GlcNAc proteome of the developing Drosophila embryo, identifying, among others, known regulators of Hox genes as candidate conveyors of OGT function during embryonic development.
Collapse
Affiliation(s)
- Nithya Selvan
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK
| | - Ritchie Williamson
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK
| | - Daniel Mariappa
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.,Division of Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - David G Campbell
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK
| | - Robert Gourlay
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK
| | - Andrew T Ferenbach
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.,Division of Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Tonia Aristotelous
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
| | - Iva Hopkins-Navratilova
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, UK
| | - Matthias Trost
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.,Institute for Cell and Molecular Biosciences (ICaMB), Newcastle University, Newcastle-upon-Tyne, UK
| | - Daan M F van Aalten
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, UK.,Division of Gene Regulation and Expression, University of Dundee, Dundee, UK
| |
Collapse
|
13
|
Yeung K, Boija A, Karlsson E, Holmqvist PH, Tsatskis Y, Nisoli I, Yap D, Lorzadeh A, Moksa M, Hirst M, Aparicio S, Fanto M, Stenberg P, Mannervik M, McNeill H. Atrophin controls developmental signaling pathways via interactions with Trithorax-like. eLife 2017; 6:e23084. [PMID: 28327288 PMCID: PMC5409829 DOI: 10.7554/elife.23084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/15/2017] [Indexed: 12/30/2022] Open
Abstract
Mutations in human Atrophin1, a transcriptional corepressor, cause dentatorubral-pallidoluysian atrophy, a neurodegenerative disease. Drosophila Atrophin (Atro) mutants display many phenotypes, including neurodegeneration, segmentation, patterning and planar polarity defects. Despite Atro's critical role in development and disease, relatively little is known about Atro's binding partners and downstream targets. We present the first genomic analysis of Atro using ChIP-seq against endogenous Atro. ChIP-seq identified 1300 potential direct targets of Atro including engrailed, and components of the Dpp and Notch signaling pathways. We show that Atro regulates Dpp and Notch signaling in larval imaginal discs, at least partially via regulation of thickveins and fringe. In addition, bioinformatics analyses, sequential ChIP and coimmunoprecipitation experiments reveal that Atro interacts with the Drosophila GAGA Factor, Trithorax-like (Trl), and they bind to the same loci simultaneously. Phenotypic analyses of Trl and Atro clones suggest that Atro is required to modulate the transcription activation by Trl in larval imaginal discs. Taken together, these data indicate that Atro is a major Trl cofactor that functions to moderate developmental gene transcription.
Collapse
Affiliation(s)
- Kelvin Yeung
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Ann Boija
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Edvin Karlsson
- Department of Molecular Biology, Umeå University, Umeå, Sweden
- Division of CBRN Security and Defence, FOI-Swedish Defence Research Agency, Umeå, Sweden
| | - Per-Henrik Holmqvist
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Yonit Tsatskis
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Ilaria Nisoli
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King’s College London, London, United Kingdom
| | - Damian Yap
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Alireza Lorzadeh
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Michelle Moksa
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Martin Hirst
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Michael Smith Laboratories, Vancouver, Canada
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, Canada
| | - Samuel Aparicio
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Manolis Fanto
- Department of Basic and Clinical Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King’s College London, London, United Kingdom
| | - Per Stenberg
- Department of Molecular Biology, Umeå University, Umeå, Sweden
- Division of CBRN Security and Defence, FOI-Swedish Defence Research Agency, Umeå, Sweden
| | - Mattias Mannervik
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Helen McNeill
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| |
Collapse
|
14
|
Wang H, Gui H, Rallo MS, Xu Z, Matise MP. Atrophin protein RERE positively regulates Notch targets in the developing vertebrate spinal cord. J Neurochem 2017; 141:347-357. [PMID: 28144959 DOI: 10.1111/jnc.13969] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 01/24/2017] [Accepted: 01/26/2017] [Indexed: 12/12/2022]
Abstract
The Notch signaling pathway controls cell fate decision, proliferation, and other biological functions in both vertebrates and invertebrates. Precise regulation of the canonical Notch pathway ensures robustness of the signal throughout development and adult tissue homeostasis. Aberrant Notch signaling results in profound developmental defects and is linked to many human diseases. In this study, we identified the Atrophin family protein RERE (also called Atro2) as a positive regulator of Notch target Hes genes in the developing vertebrate spinal cord. Prior studies have shown that during early embryogenesis in mouse and zebrafish, deficit of RERE causes various patterning defects in multiple organs including the neural tube. Here, we detected the expression of RERE in the developing chick spinal cord, and found that normal RERE activity is needed for proper neural progenitor proliferation and neuronal differentiation possibly by affecting Notch-mediated Hes expression. In mammalian cells, RERE co-immunoprecipitates with CBF1 and Notch intracellular domain (NICD), and is recruited to nuclear foci formed by over-expressed NICD1. RERE is also necessary for NICD to activate the expression of Notch target genes. Our findings suggest that RERE stimulates Notch target gene expression by preventing degradation of NICD protein, thereby facilitating the assembly of a transcriptional activating complex containing NICD, CBF1/RBPjκ in vertebrate, Su(H) in Drosophila melanogaster, Lag1 in C. elegans, and other coactivators.
Collapse
Affiliation(s)
- Hui Wang
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, China.,Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School of Rutgers University, Piscataway, New Jersey, USA
| | - Hongxing Gui
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School of Rutgers University, Piscataway, New Jersey, USA
| | - Michael S Rallo
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School of Rutgers University, Piscataway, New Jersey, USA
| | - Zhiyan Xu
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, China
| | - Michael P Matise
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School of Rutgers University, Piscataway, New Jersey, USA
| |
Collapse
|
15
|
Modulation of Molecular Chaperones in Huntington’s Disease and Other Polyglutamine Disorders. Mol Neurobiol 2016; 54:5829-5854. [DOI: 10.1007/s12035-016-0120-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 09/12/2016] [Indexed: 12/20/2022]
|
16
|
Huang H, Kornberg TB. Cells must express components of the planar cell polarity system and extracellular matrix to support cytonemes. eLife 2016; 5. [PMID: 27591355 PMCID: PMC5030081 DOI: 10.7554/elife.18979] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 08/31/2016] [Indexed: 01/10/2023] Open
Abstract
Drosophila dorsal air sac development depends on Decapentaplegic (Dpp) and Fibroblast growth factor (FGF) proteins produced by the wing imaginal disc and transported by cytonemes to the air sac primordium (ASP). Dpp and FGF signaling in the ASP was dependent on components of the planar cell polarity (PCP) system in the disc, and neither Dpp- nor FGF-receiving cytonemes extended over mutant disc cells that lacked them. ASP cytonemes normally navigate through extracellular matrix (ECM) composed of collagen, laminin, Dally and Dally-like (Dlp) proteins that are stratified in layers over the disc cells. However, ECM over PCP mutant cells had reduced levels of laminin, Dally and Dlp, and whereas Dpp-receiving ASP cytonemes navigated in the Dally layer and required Dally (but not Dlp), FGF-receiving ASP cytonemes navigated in the Dlp layer, requiring Dlp (but not Dally). These findings suggest that cytonemes interact directly and specifically with proteins in the stratified ECM.
Collapse
Affiliation(s)
- Hai Huang
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
| | - Thomas B Kornberg
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, United States
| |
Collapse
|
17
|
Thomas AL, Davis SM, Dierick HA. Of Fighting Flies, Mice, and Men: Are Some of the Molecular and Neuronal Mechanisms of Aggression Universal in the Animal Kingdom? PLoS Genet 2015; 11:e1005416. [PMID: 26312756 PMCID: PMC4551476 DOI: 10.1371/journal.pgen.1005416] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Aggressive behavior is widespread in the animal kingdom, but the degree of molecular conservation between distantly related species is still unclear. Recent reports suggest that at least some of the molecular mechanisms underlying this complex behavior in flies show remarkable similarities with such mechanisms in mice and even humans. Surprisingly, some aspects of neuronal control of aggression also show remarkable similarity between these distantly related species. We will review these recent findings, address the evolutionary implications, and discuss the potential impact for our understanding of human diseases characterized by excessive aggression.
Collapse
Affiliation(s)
- Amanda L. Thomas
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Shaun M. Davis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Herman A. Dierick
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
| |
Collapse
|
18
|
Xu Z, Tito AJ, Rui YN, Zhang S. Studying polyglutamine diseases in Drosophila. Exp Neurol 2015; 274:25-41. [PMID: 26257024 DOI: 10.1016/j.expneurol.2015.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 08/02/2015] [Accepted: 08/03/2015] [Indexed: 12/16/2022]
Abstract
Polyglutamine (polyQ) diseases are a family of dominantly transmitted neurodegenerative disorders caused by an abnormal expansion of CAG trinucleotide repeats in the protein-coding regions of the respective disease-causing genes. Despite their simple genetic basis, the etiology of these diseases is far from clear. Over the past two decades, Drosophila has proven to be successful in modeling this family of neurodegenerative disorders, including the faithful recapitulation of pathological features such as polyQ length-dependent formation of protein aggregates and progressive neuronal degeneration. Additionally, it has been valuable in probing the pathogenic mechanisms, in identifying and evaluating disease modifiers, and in helping elucidate the normal functions of disease-causing genes. Knowledge learned from this simple invertebrate organism has had a large impact on our understanding of these devastating brain diseases.
Collapse
Affiliation(s)
- Zhen Xu
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Antonio Joel Tito
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; Programs in Human and Molecular Genetics and Neuroscience, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Graduate School of Biomedical Sciences, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Yan-Ning Rui
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States
| | - Sheng Zhang
- The Brown Foundation Institute of Molecular Medicine, 1825 Pressler Street, Houston, TX 77030, United States; Department of Neurobiology and Anatomy, 1825 Pressler Street, Houston, TX 77030, United States; Programs in Human and Molecular Genetics and Neuroscience, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Graduate School of Biomedical Sciences, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Medical School at Houston, 1825 Pressler Street, Houston, TX 77030, United States; The University of Texas Health Science Center at Houston (UTHealth), 1825 Pressler Street, Houston, TX 77030, United States.
| |
Collapse
|
19
|
Xiong Y, Liu C, Zhao Y. Decoding Ci: from partial degradation to inhibition. Dev Growth Differ 2014; 57:98-108. [PMID: 25495033 DOI: 10.1111/dgd.12187] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/29/2014] [Accepted: 10/30/2014] [Indexed: 11/28/2022]
Abstract
Hedgehog is a morphogen, which is widely involved in the regulation of cell proliferation, differentiation and tissue patterning during development in both vertebrate and invertebrate, such as in coordination of eye, brain, gonad, gut and tracheal development. In invertebrate, Cubitus interruptus (Ci) modification process is the last identified step before transcriptional activation in the Hh signaling pathway. Ci can form a truncated repressor (Ci(R) /Ci75) or act as an activator (Ci(A) /Ci155) based on Hh gradient to regulate the expressions of target genes. The activity of Ci is mediated by different mechanisms, including processing, trafficking and degradation. While in vertebrate, Glioblastomas (Glis), homologs of Ci, play similar but more complex roles in the regulation of mammals Hh pathway. Hh signaling is responsible for a wide variety of processes during embryonic development and adult tissue homeostasis. Malfunction of Hh signaling could cause various diseases including birth defects and cancers. Enormous efforts were made in the past decades to explore the Hh pathway regulation and the results have provided us important insights into disease diagnosis and therapeutic treatment. In this review, we focus on a small branch of Hh pathway regulation based on studies in the Drosophila system, mainly about Ci degradation, aiming to explain how Ci is modified by different ubiquitin ligases due to the strong or moderate Hh signals and then been subjected to complete or partial degradation by proteasomes. Overall, we intend to offer an overview on how Ci responds to and relays Hh signals in a precise manner to control target genes expressions and ensures proper Hh signal transduction.
Collapse
Affiliation(s)
- Yue Xiong
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | | | | |
Collapse
|
20
|
Le Pabic P, Ng C, Schilling TF. Fat-Dachsous signaling coordinates cartilage differentiation and polarity during craniofacial development. PLoS Genet 2014; 10:e1004726. [PMID: 25340762 PMCID: PMC4207671 DOI: 10.1371/journal.pgen.1004726] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 09/02/2014] [Indexed: 11/19/2022] Open
Abstract
Organogenesis requires coordinated regulation of cellular differentiation and morphogenesis. Cartilage cells in the vertebrate skeleton form polarized stacks, which drive the elongation and shaping of skeletal primordia. Here we show that an atypical cadherin, Fat3, and its partner Dachsous-2 (Dchs2), control polarized cell-cell intercalation of cartilage precursors during craniofacial development. In zebrafish embryos deficient in Fat3 or Dchs2, chondrocytes fail to stack and misregulate expression of sox9a. Similar morphogenetic defects occur in rerea/atr2a−/− mutants, and Fat3 binds REREa, consistent with a model in which Fat3, Dchs2 and REREa interact to control polarized cell-cell intercalation and simultaneously control differentiation through Sox9. Chimaeric analyses support such a model, and reveal long-range influences of all three factors, consistent with the activation of a secondary signal that regulates polarized cell-cell intercalation. This coordinates the spatial and temporal morphogenesis of chondrocytes to shape skeletal primordia and defects in these processes underlie human skeletal malformations. Similar links between cell polarity and differentiation mechanisms are also likely to control organ formation in other contexts. Little is known about the mechanisms of cell-cell communication necessary to assemble skeletal elements of appropriate size and shape. In this study, we investigate the roles of genetic factors belonging to a developmental pathway that affects skeletal progenitor behavior: the atypical cadherins Fat3 and Dachsous2 (Dchs2), and REREa/Atr2a. We show that cartilage precursors fail to rearrange into linear stacks and at the same time misregulate expression of sox9a, a key regulator of cartilage differentiation, in zebrafish embryos deficient in Fat3 or its partner Dchs2. Similar cartilage defects are observed in rerea−/− mutants, and Fat3 interacts physically and genetically with REREa. Our results suggest that Fat3, Dchs2 and REREa interact to control polarized cell-cell intercalation and simultaneously control skeletal differentiation through Sox9. By transplanting cartilage precursors between wild-type and Fat3, Dchs2 or REREa deficient embryos we demonstrate that all three factors exert long-range influences on neighboring cells, most likely mediated by another polarizing signal. We propose a model in which this coordinates the polarity and differentiation of chondrocytes to shape skeletal primordia, and that defects in these processes underlie human skeletal malformations.
Collapse
Affiliation(s)
- Pierre Le Pabic
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, California, United States of America
| | - Carrie Ng
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, California, United States of America
| | - Thomas F. Schilling
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, California, United States of America
- * E-mail:
| |
Collapse
|
21
|
Islam MM, Zhang CL. TLX: A master regulator for neural stem cell maintenance and neurogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:210-6. [PMID: 24930777 DOI: 10.1016/j.bbagrm.2014.06.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 04/22/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
The orphan nuclear receptor TLX, also known as NR2E1, is an essential regulator of neural stem cell (NSC) self-renewal, maintenance, and neurogenesis. In vertebrates, TLX is specifically localized to the neurogenic regions of the forebrain and retina throughout development and adulthood. TLX regulates the expression of genes involved in multiple pathways, such as the cell cycle, DNA replication, and cell adhesion. These roles are primarily performed through the transcriptional repression or activation of downstream target genes. Emerging evidence suggests that the misregulation of TLX might play a role in the onset and progression of human neurological disorders making this factor an ideal therapeutic target. Here, we review the current understanding of TLX function, expression, regulation, and activity significant to NSC maintenance, adult neurogenesis, and brain plasticity. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
Collapse
Affiliation(s)
- Mohammed M Islam
- Department of Molecular Biology, 6000 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, 6000 Harry Hines Blvd., Dallas, TX 75390, USA.
| |
Collapse
|
22
|
Matilla-Dueñas A, Ashizawa T, Brice A, Magri S, McFarland KN, Pandolfo M, Pulst SM, Riess O, Rubinsztein DC, Schmidt J, Schmidt T, Scoles DR, Stevanin G, Taroni F, Underwood BR, Sánchez I. Consensus paper: pathological mechanisms underlying neurodegeneration in spinocerebellar ataxias. CEREBELLUM (LONDON, ENGLAND) 2014; 13:269-302. [PMID: 24307138 PMCID: PMC3943639 DOI: 10.1007/s12311-013-0539-y] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Intensive scientific research devoted in the recent years to understand the molecular mechanisms or neurodegeneration in spinocerebellar ataxias (SCAs) are identifying new pathways and targets providing new insights and a better understanding of the molecular pathogenesis in these diseases. In this consensus manuscript, the authors discuss their current views on the identified molecular processes causing or modulating the neurodegenerative phenotype in spinocerebellar ataxias with the common opinion of translating the new knowledge acquired into candidate targets for therapy. The following topics are discussed: transcription dysregulation, protein aggregation, autophagy, ion channels, the role of mitochondria, RNA toxicity, modulators of neurodegeneration and current therapeutic approaches. Overall point of consensus includes the common vision of neurodegeneration in SCAs as a multifactorial, progressive and reversible process, at least in early stages. Specific points of consensus include the role of the dysregulation of protein folding, transcription, bioenergetics, calcium handling and eventual cell death with apoptotic features of neurons during SCA disease progression. Unresolved questions include how the dysregulation of these pathways triggers the onset of symptoms and mediates disease progression since this understanding may allow effective treatments of SCAs within the window of reversibility to prevent early neuronal damage. Common opinions also include the need for clinical detection of early neuronal dysfunction, for more basic research to decipher the early neurodegenerative process in SCAs in order to give rise to new concepts for treatment strategies and for the translation of the results to preclinical studies and, thereafter, in clinical practice.
Collapse
Affiliation(s)
- A Matilla-Dueñas
- Health Sciences Research Institute Germans Trias i Pujol (IGTP), Ctra. de Can Ruti, Camí de les Escoles s/n, Badalona, Barcelona, Spain,
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Zhang Z, Feng J, Pan C, Lv X, Wu W, Zhou Z, Liu F, Zhang L, Zhao Y. Atrophin-Rpd3 complex represses Hedgehog signaling by acting as a corepressor of CiR. ACTA ACUST UNITED AC 2014; 203:575-83. [PMID: 24385484 PMCID: PMC3840934 DOI: 10.1083/jcb.201306012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The evolutionarily conserved Hedgehog (Hh) signaling pathway is transduced by the Cubitus interruptus (Ci)/Gli family of transcription factors that exist in two distinct repressor (Ci(R)/Gli(R)) and activator (Ci(A)/Gli(A)) forms. Aberrant activation of Hh signaling is associated with various human cancers, but the mechanism through which Ci(R)/Gli(R) properly represses target gene expression is poorly understood. Here, we used Drosophila melanogaster and zebrafish models to define a repressor function of Atrophin (Atro) in Hh signaling. Atro directly bound to Ci through its C terminus. The N terminus of Atro interacted with a histone deacetylase, Rpd3, to recruit it to a Ci-binding site at the decapentaplegic (dpp) locus and reduce dpp transcription through histone acetylation regulation. The repressor function of Atro in Hh signaling was dependent on Ci. Furthermore, Rerea, a homologue of Atro in zebrafish, repressed the expression of Hh-responsive genes. We propose that the Atro-Rpd3 complex plays a conserved role to function as a Ci(R) corepressor.
Collapse
Affiliation(s)
- Zhao Zhang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Singh J, Mlodzik M. Planar cell polarity signaling: coordination of cellular orientation across tissues. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2014; 1:479-99. [PMID: 23066429 DOI: 10.1002/wdev.32] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Establishment of Planar Cell Polarity (PCP) in epithelia, in the plane of an epithelium, is an important feature of the development and homeostasis of most organs. Studies in different model organisms have contributed a wealth of information regarding the mechanisms that govern PCP regulation. Genetic studies in Drosophila have identified two signaling systems, the Fz/PCP and Fat/Dachsous system, which are both required for PCP establishment in many different tissues in a largely non-redundant manner. Recent advances in vertebrate PCP studies have added novel factors of PCP regulation and also new cellular features requiring PCP-signaling input, including the positioning and orientation of the primary cilium of many epithelial cells. This review focuses mostly on several recent advances made in the Drosophila and vertebrate PCP field and integrates these within the existing PCP-signaling framework.
Collapse
Affiliation(s)
- Jaskirat Singh
- Department of Developmental & Regenerative Biology, Mount Sinai School of Medicine, New York, NY, USA
| | | |
Collapse
|
25
|
Rogers WA, Grover S, Stringer SJ, Parks J, Rebeiz M, Williams TM. A survey of the trans-regulatory landscape for Drosophila melanogaster abdominal pigmentation. Dev Biol 2014; 385:417-32. [DOI: 10.1016/j.ydbio.2013.11.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 10/07/2013] [Accepted: 11/05/2013] [Indexed: 10/26/2022]
|
26
|
Alkhori L, Öst A, Alenius M. The corepressor Atrophin specifies odorant receptor expression in Drosophila. FASEB J 2013; 28:1355-64. [PMID: 24334704 DOI: 10.1096/fj.13-240325] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In both insects and vertebrates, each olfactory sensory neuron (OSN) expresses one odorant receptor (OR) from a large genomic repertoire. How a receptor is specified is a tantalizing question addressing fundamental aspects of cell differentiation. Here, we demonstrate that the corepressor Atrophin (Atro) segregates OR gene expression between OSN classes in Drosophila. We show that the knockdown of Atro result in either loss or gain of a broad set of ORs. Each OR phenotypic group correlated with one of two opposing Notch fates, Notch responding, Nba (N(on)), and nonresponding, Nab (N(off)) OSNs. Our data show that Atro segregates ORs expressed in the Nba OSN classes and helps establish the Nab fate during OSN development. Consistent with a role in recruiting histone deacetylates, immunohistochemistry revealed that Atro regulates global histone 3 acetylation (H3ac) in OSNs and requires Hdac3 to segregate OR gene expression. We further found that Nba OSN classes exhibit variable but higher H3ac levels than the Nab OSNs. Together, these data suggest that Atro determines the level of H3ac, which ensures correct OR gene expression within the Nba OSNs. We propose a mechanism by which a single corepressor can specify a large number of neuron classes.
Collapse
Affiliation(s)
- Liza Alkhori
- 1Department of Clinical and Experimental Medicine, Linköping University, S-581 83 Linköping, Sweden.
| | | | | |
Collapse
|
27
|
Mannervik M. Control of Drosophila embryo patterning by transcriptional co-regulators. Exp Cell Res 2013; 321:47-57. [PMID: 24157250 DOI: 10.1016/j.yexcr.2013.10.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 10/10/2013] [Accepted: 10/14/2013] [Indexed: 12/29/2022]
Abstract
A combination of broadly expressed transcriptional activators and spatially restricted repressors are used to pattern embryos into cells of different fate. Transcriptional co-regulators are essential mediators of transcription factor function, and contribute to selective transcriptional responses in embryo development. A two step mechanism of transcriptional regulation is discussed, where remodeling of chromatin is initially required, followed by stimulation of recruitment or release of RNA polymerase from the promoter. Transcriptional co-regulators are essential for both of these steps. In particular, most co-activators are associated with histone acetylation and co-repressors with histone deacetylation. In the early Drosophila embryo, genome-wide studies have shown that the CBP co-activator has a preference for associating with some transcription factors and regulatory regions. The Groucho, CtBP, Ebi, Atrophin and Brakeless co-repressors are selectively used to limit zygotic gene expression. New findings are summarized which show that different co-repressors are often utilized by a single repressor, that the context in which a co-repressor is recruited to DNA can affect its activity, and that co-regulators may switch from co-repressors to co-activators and vice versa. The possibility that co-regulator activity is regulated and plays an instructive role in development is discussed as well. This review highlights how findings in Drosophila embryos have contributed to the understanding of transcriptional regulation in eukaryotes as well as to mechanisms of animal embryo patterning.
Collapse
Affiliation(s)
- Mattias Mannervik
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Arrheniuslaboratories E3, SE-106 91 Stockholm, Sweden.
| |
Collapse
|
28
|
Sharma P, McNeill H. Regulation of long-range planar cell polarity by Fat-Dachsous signaling. Development 2013; 140:3869-81. [PMID: 23946440 DOI: 10.1242/dev.094730] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fat (Ft) and Dachsous (Ds) are large cadherins that bind each other and have conserved roles in regulating planar cell polarity (PCP). We quantitatively analyzed Ft-Ds pathway mutant clones for their effects on ommatidial polarity in the Drosophila eye. Our findings suggest that the Ft-Ds pathway regulates PCP propagation independently of asymmetric cellular accumulation of Ft or Ds. We find that the Ft effector Atrophin has a position-specific role in regulating polarity in the eye, and that asymmetric accumulation of the atypical myosin Dachs is not essential for production and propagation of a long-range PCP signal. Our observations suggest that Ft and Ds interact to modulate a secondary signal that regulates long-range polarity, that signaling by the Ds intracellular domain is dependent on Ft, and that ommatidial fate specification is genetically separable from long-range signaling.
Collapse
Affiliation(s)
- Praveer Sharma
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | | |
Collapse
|
29
|
Ramey HR, Decker JE, McKay SD, Rolf MM, Schnabel RD, Taylor JF. Detection of selective sweeps in cattle using genome-wide SNP data. BMC Genomics 2013; 14:382. [PMID: 23758707 PMCID: PMC3681554 DOI: 10.1186/1471-2164-14-382] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 05/24/2013] [Indexed: 12/25/2022] Open
Abstract
Background The domestication and subsequent selection by humans to create breeds and biological types of cattle undoubtedly altered the patterning of variation within their genomes. Strong selection to fix advantageous large-effect mutations underlying domesticability, breed characteristics or productivity created selective sweeps in which variation was lost in the chromosomal region flanking the selected allele. Selective sweeps have now been identified in the genomes of many animal species including humans, dogs, horses, and chickens. Here, we attempt to identify and characterise regions of the bovine genome that have been subjected to selective sweeps. Results Two datasets were used for the discovery and validation of selective sweeps via the fixation of alleles at a series of contiguous SNP loci. BovineSNP50 data were used to identify 28 putative sweep regions among 14 diverse cattle breeds. Affymetrix BOS 1 prescreening assay data for five breeds were used to identify 85 regions and validate 5 regions identified using the BovineSNP50 data. Many genes are located within these regions and the lack of sequence data for the analysed breeds precludes the nomination of selected genes or variants and limits the prediction of the selected phenotypes. However, phenotypes that we predict to have historically been under strong selection include horned-polled, coat colour, stature, ear morphology, and behaviour. Conclusions The bias towards common SNPs in the design of the BovineSNP50 assay led to the identification of recent selective sweeps associated with breed formation and common to only a small number of breeds rather than ancient events associated with domestication which could potentially be common to all European taurines. The limited SNP density, or marker resolution, of the BovineSNP50 assay significantly impacted the rate of false discovery of selective sweeps, however, we found sweeps in common between breeds which were confirmed using an ultra-high-density assay scored in a small number of animals from a subset of the breeds. No sweep regions were shared between indicine and taurine breeds reflecting their divergent selection histories and the very different environmental habitats to which these sub-species have adapted.
Collapse
Affiliation(s)
- Holly R Ramey
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | | | | | | | | | | |
Collapse
|
30
|
Marcinkevicius E, Zallen JA. Regulation of cytoskeletal organization and junctional remodeling by the atypical cadherin Fat. Development 2013; 140:433-43. [PMID: 23250217 DOI: 10.1242/dev.083949] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The atypical cadherin Fat is a conserved regulator of planar cell polarity, but the mechanisms by which Fat controls cell shape and tissue structure are not well understood. Here, we show that Fat is required for the planar polarized organization of actin denticle precursors, adherens junction proteins and microtubules in the epidermis of the late Drosophila embryo. In wild-type embryos, spatially regulated cell-shape changes and rearrangements organize cells into highly aligned columns. Junctional remodeling is suppressed at dorsal and ventral cell boundaries, where adherens junction proteins accumulate. By contrast, adherens junction proteins fail to accumulate to the wild-type extent and all cell boundaries are equally engaged in junctional remodeling in fat mutants. The effects of loss of Fat on cell shape and junctional localization, but not its role in denticle organization, are recapitulated by mutations in Expanded, an upstream regulator of the conserved Hippo pathway, and mutations in Hippo and Warts, two kinases in the Hippo kinase cascade. However, the cell shape and planar polarity defects in fat mutants are not suppressed by removing the transcriptional co-activator Yorkie, suggesting that these roles of Fat are independent of Yorkie-mediated transcription. The effects of Fat on cell shape, junctional remodeling and microtubule localization are recapitulated by expression of activated Notch. These results demonstrate that cell shape, junctional localization and cytoskeletal planar polarity in the Drosophila embryo are regulated by a common signal provided by the atypical cadherin Fat and suggest that Fat influences tissue organization through its role in polarized junctional remodeling.
Collapse
Affiliation(s)
- Emily Marcinkevicius
- Howard Hughes Medical Institute and Developmental Biology Program, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065, USA
| | | |
Collapse
|
31
|
Camero S, Benítez MJ, Jiménez JS. Anomalous Protein–DNA Interactions Behind Neurological Disorders. PROTEIN-NUCLEIC ACIDS INTERACTIONS 2013; 91:37-63. [DOI: 10.1016/b978-0-12-411637-5.00002-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
32
|
Sharma P, McNeill H. Fat and Dachsous cadherins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 116:215-35. [PMID: 23481197 DOI: 10.1016/b978-0-12-394311-8.00010-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fat and Dachsous (Ds) are very large cell adhesion molecules. They bind each other and have important, highly conserved roles in planar cell polarity (PCP) and growth control. PCP is defined as the directionally coordinated development of cellular structures or behavior. Cellular and tissue growth needs to be modulated in terms of rate and final size, and the Hippo pathway regulates growth in a variety of developmental contexts. Fat and Ds are important upstream regulators of these pathways. There are two Fat proteins in Drosophila, Fat and Fat2, and four in vertebrates, Fat1-4. There is one Ds protein in Drosophila and two in vertebrates, Dachsous1-2. In this chapter, we discuss the roles of Fat and Ds family members, focusing on Drosophila and mouse development.
Collapse
|
33
|
Silveira H, Gabriel A, Ramos S, Palma J, Felix R, Custódio A, Collins LV. CpG-containing oligodeoxynucleotides increases resistance of Anopheles mosquitoes to Plasmodium infection. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 42:758-765. [PMID: 22885118 DOI: 10.1016/j.ibmb.2012.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 07/08/2012] [Accepted: 07/16/2012] [Indexed: 06/01/2023]
Abstract
Unmethylated CpG dinucleotide motifs in bacterial DNA or in synthetic oligodeoxynucleotides (ODN) are potent stimulators of the vertebrate innate immune system. However, the potential of these DNA species to modulate mosquito immunity have not been explored. In the present study, we investigated the effects of CpG-ODN on the outcome of Plasmodium infection in insects and on the modulation of mosquito immunity to Plasmodium. Anopheles stephensi and Anopheles gambiae mosquitoes inoculated with CpG-ODN showed significant reductions in the prevalence of Plasmodium infection, intensity of Plasmodium infection, and number of eggs produced. Microarrays were used to elucidate the transcriptional profiles of the fat bodies of CpG-ODN-treated mosquitoes. In total, 172 genes were differentially expressed, of which 136 were up-regulated and 36 were down-regulated. The major functional class of CpG-ODN-regulated genes encoded immune response-related proteins (31%). Within this group, genes associated with coagulation/wound healing were the most frequently represented (23%). Knockdown of a transglutaminase gene that was up-regulated by the CpG-ODN and chemical inhibition of the enzyme resulted in a significant increase in Plasmodium infection. Mosquitoes that were treated with CpG-ODNs were found to be less susceptible to Plasmodium infection. Transcriptional profiling of the fat body suggests that protection is associated with coagulation/wound healing. We show for the first time that transglutaminase activity plays a role in the control of Plasmodium infection.
Collapse
Affiliation(s)
- Henrique Silveira
- Centro de Malária e Outras Doenças Tropicais, UEI Parasitologia Médica, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira, 100, 1349-008 Lisboa, Portugal.
| | | | | | | | | | | | | |
Collapse
|
34
|
Estruch SB, Buzón V, Carbó LR, Schorova L, Lüders J, Estébanez-Perpiñá E. The oncoprotein BCL11A binds to orphan nuclear receptor TLX and potentiates its transrepressive function. PLoS One 2012; 7:e37963. [PMID: 22675500 PMCID: PMC3366998 DOI: 10.1371/journal.pone.0037963] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 05/01/2012] [Indexed: 12/12/2022] Open
Abstract
Nuclear orphan receptor TLX (NR2E1) functions primarily as a transcriptional repressor and its pivotal role in brain development, glioblastoma, mental retardation and retinopathologies make it an attractive drug target. TLX is expressed in the neural stem cells (NSCs) of the subventricular zone and the hippocampus subgranular zone, regions with persistent neurogenesis in the adult brain, and functions as an essential regulator of NSCs maintenance and self-renewal. Little is known about the TLX social network of interactors and only few TLX coregulators are described. To identify and characterize novel TLX-binders and possible coregulators, we performed yeast-two-hybrid (Y2H) screens of a human adult brain cDNA library using different TLX constructs as baits. Our screens identified multiple clones of Atrophin-1 (ATN1), a previously described TLX interactor. In addition, we identified an interaction with the oncoprotein and zinc finger transcription factor BCL11A (CTIP1/Evi9), a key player in the hematopoietic system and in major blood-related malignancies. This interaction was validated by expression and coimmunoprecipitation in human cells. BCL11A potentiated the transrepressive function of TLX in an in vitro reporter gene assay. Our work suggests that BCL11A is a novel TLX coregulator that might be involved in TLX-dependent gene regulation in the brain.
Collapse
Affiliation(s)
- Sara B. Estruch
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine from the University of Barcelona, University of Barcelona, Barcelona, Spain
| | - Víctor Buzón
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine from the University of Barcelona, University of Barcelona, Barcelona, Spain
| | - Laia R. Carbó
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine from the University of Barcelona, University of Barcelona, Barcelona, Spain
| | - Lenka Schorova
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine from the University of Barcelona, University of Barcelona, Barcelona, Spain
| | - Jens Lüders
- Cell and Developmental Biology Programme, Institute for Research in Biomedicine, Barcelona, Spain
| | - Eva Estébanez-Perpiñá
- Department of Biochemistry and Molecular Biology and Institute of Biomedicine from the University of Barcelona, University of Barcelona, Barcelona, Spain
- * E-mail:
| |
Collapse
|
35
|
Fujioka M, Gebelein B, Cofer ZC, Mann RS, Jaynes JB. Engrailed cooperates directly with Extradenticle and Homothorax on a distinct class of homeodomain binding sites to repress sloppy paired. Dev Biol 2012; 366:382-92. [PMID: 22537495 DOI: 10.1016/j.ydbio.2012.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 03/25/2012] [Accepted: 04/07/2012] [Indexed: 10/28/2022]
Abstract
Even skipped (Eve) and Engrailed (En) are homeodomain-containing transcriptional repressors with similar DNA binding specificities that are sequentially expressed in Drosophila embryos. The sloppy-paired (slp) locus is a target of repression by both Eve and En. At blastoderm, Eve is expressed in 7 stripes that restrict the posterior border of slp stripes, allowing engrailed (en) gene expression to be initiated in odd-numbered parasegments. En, in turn, prevents expansion of slp stripes after Eve is turned off. Prior studies showed that the two tandem slp transcription units are regulated by cis-regulatory modules (CRMs) with activities that overlap in space and time. An array of CRMs that generate 7 stripes at blastoderm, and later 14 stripes, surround slp1 (Fujioka and Jaynes, 2012). Surprisingly given their similarity in DNA binding specificity and function, responsiveness to ectopic Eve and En indicates that most of their direct target sites are either in distinct CRMs, or in different parts of coregulated CRMs. We localized cooperative binding sites for En, with the homeodomain-containing Hox cofactors Extradenticle (Exd) and Homothorax (Hth), within two CRMs that drive similar expression patterns. Functional analysis revealed two distinct, redundant sites within one CRM. The other CRM contains a single cooperative site that is both necessary and sufficient for repression in the en domain. Correlating in vivo and in vitro analysis suggests that cooperativity with Exd and Hth is a key ingredient in the mechanism of En-dependent repression, and that apparent affinity in vitro is an unreliable predictor of in vivo function.
Collapse
Affiliation(s)
- Miki Fujioka
- Department of Biochemistry and Molecular Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | | | | | | | | |
Collapse
|
36
|
Suzuki K, Zhou J, Sato T, Takao K, Miyagawa T, Oyake M, Yamada M, Takahashi H, Takahashi Y, Goto J, Tsuji S. DRPLA transgenic mouse substrains carrying single copy of full-length mutant human DRPLA gene with variable sizes of expanded CAG repeats exhibit CAG repeat length- and age-dependent changes in behavioral abnormalities and gene expression profiles. Neurobiol Dis 2012; 46:336-50. [PMID: 22342974 DOI: 10.1016/j.nbd.2012.01.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 12/31/2011] [Accepted: 01/26/2012] [Indexed: 01/21/2023] Open
Abstract
Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant progressive neurodegenerative disorder with intellectual deterioration and various motor deficits including ataxia, choreoathetosis, and myoclonus, caused by an abnormal expansion of CAG repeats in the DRPLA gene. Longer expanded CAG repeats contribute to an earlier age of onset, faster progression, and more severe neurological symptoms in DRPLA patients. In this study, we have established DRPLA transgenic mouse lines (sublines) harboring a single copy of the full-length mutant human DRPLA gene carrying various lengths of expanded CAG repeats (Q76, Q96, Q113, and Q129), which have clearly shown motor deficits and memory disturbance whose severity increases with the length of expanded CAG repeats and age, and successfully replicated the CAG repeat length- and age-dependent features of DRPLA patients. Neuronal intranuclear accumulation of the mutant DRPLA protein has been suggested to cause transcriptional dysregulation, leading to alteration in gene expression and neuronal dysfunction. In this study, we have conducted a comprehensive analysis of gene expression profiles in the cerebrum and cerebellum of transgenic mouse lines at 4, 8, and 12 weeks using multiple microarray platforms, and demonstrated that both the number and expression levels of the altered genes are highly dependent on CAG repeat length and age in both brain regions. Specific groups of genes and their function categories were identified by further agglomerative cluster analysis and gene functional annotation analysis. Calcium signaling and neuropeptide signaling, among others, were implicated in the pathophysiology of DRPLA. Our study provides unprecedented CAG-repeat-length-dependent mouse models of DRPLA, which are highly valuable not only for elucidating the CAG-repeat-length-dependent pathophysiology of DRPLA but also for developing therapeutic strategies for DRPLA.
Collapse
Affiliation(s)
- Kazushi Suzuki
- Department of Neurology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Abstract
Over the past 20 years, nucleotide repeat expansion disorders have informed our broader understanding of neurodevelopmental and neurodegenerative disease. This is especially true with regard to the contributions of epigenetic mechanisms to neurologic disease pathogenesis. In this review, the authors describe a few of the myriad ways in which epigenetic processes underlie aspects of repeat expansion disorder pathophysiology and discuss how therapies targeted at epigenetic modulation hold promise for many of these disorders.
Collapse
Affiliation(s)
- Fang He
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109, USA
| | | |
Collapse
|
38
|
Abstract
Dentatorubral-pallidoluysian atrophy (DRPLA) is a rare autosomal dominant neurodegenerative disorder clinically characterized by various combinations of cerebellar ataxia, choreoathetosis, myoclonus, epilepsy, dementia, and psychiatric symptoms. The most striking clinical features of DRPLA are the considerable heterogeneity in clinical presentation, depending on the age of onset, and the prominent genetic anticipation. DRPLA is caused by unstable expansion of CAG repeats coding for polyglutamine stretches located in exon 5 of the DRPLA gene. DRPLA is characterized by prominent anticipation, with paternal transmission resulting in more prominent anticipation than does maternal transmission, which is now understood based on the intergenerational stability of the CAG repeats. DRPLA protein (also called atrophin-1) is localized in the nucleus and functions as a transcription co-regulator. Recent immunohistochemical studies on autopsied tissues of patients with DRPLA have demonstrated that diffuse accumulation of mutant DRPLA protein (atrophin-1) in the neuronal nuclei, rather than the formation of neuronal intranuclear inclusions (NIIs), is the predominant pathologic condition and involves a wide range of central nervous system regions far beyond the systems previously reported to be affected. Thus, age-dependent and CAG repeat-dependent intranuclear accumulation of mutant DRPLA leading to nuclear dysfunctions are suggested to be the essential pathophysiologic mechanisms in DRPLA.
Collapse
|
39
|
Thomas C, Strutt D. The roles of the cadherins Fat and Dachsous in planar polarity specification in Drosophila. Dev Dyn 2011; 241:27-39. [PMID: 21919123 DOI: 10.1002/dvdy.22736] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2011] [Indexed: 11/06/2022] Open
Abstract
Planar polarity is generated through the activity of two groups of proteins, the "core" system and the Fat (Ft)/Dachsous (Ds) system. Although both are conserved from insects to mammals, vertebrate studies into planar polarity have primarily focussed on core planar polarity proteins and have only recently branched into the study of the Ft/Ds system. In Drosophila, however, years of detailed analysis have started to elucidate some of the mechanisms by which Ft/Ds signalling might set up polarity across a tissue, and how this may impact upon core protein-mediated planar polarity. In this review, we discuss the major findings, models, and controversies that have emerged from Drosophila research into the Ft/Ds system, and indicate some areas for further investigation.
Collapse
Affiliation(s)
- Chloe Thomas
- MRC Centre for Developmental and Biomedical Genetics and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom.
| | | |
Collapse
|
40
|
D'Antonio M, Ciccarelli FD. Modification of gene duplicability during the evolution of protein interaction network. PLoS Comput Biol 2011; 7:e1002029. [PMID: 21490719 PMCID: PMC3072358 DOI: 10.1371/journal.pcbi.1002029] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 02/24/2011] [Indexed: 11/21/2022] Open
Abstract
Duplications of genes encoding highly connected and essential proteins are selected against in several species but not in human, where duplicated genes encode highly connected proteins. To understand when and how gene duplicability changed in evolution, we compare gene and network properties in four species (Escherichia coli, yeast, fly, and human) that are representative of the increase in evolutionary complexity, defined as progressive growth in the number of genes, cells, and cell types. We find that the origin and conservation of a gene significantly correlates with the properties of the encoded protein in the protein-protein interaction network. All four species preserve a core of singleton and central hubs that originated early in evolution, are highly conserved, and accomplish basic biological functions. Another group of hubs appeared in metazoans and duplicated in vertebrates, mostly through vertebrate-specific whole genome duplication. Such recent and duplicated hubs are frequently targets of microRNAs and show tissue-selective expression, suggesting that these are alternative mechanisms to control their dosage. Our study shows how networks modified during evolution and contributes to explaining the occurrence of somatic genetic diseases, such as cancer, in terms of network perturbations.
Collapse
Affiliation(s)
- Matteo D'Antonio
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | | |
Collapse
|
41
|
Napoletano F, Occhi S, Calamita P, Volpi V, Blanc E, Charroux B, Royet J, Fanto M. Polyglutamine Atrophin provokes neurodegeneration in Drosophila by repressing fat. EMBO J 2011; 30:945-58. [PMID: 21278706 DOI: 10.1038/emboj.2011.1] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 12/22/2010] [Indexed: 01/13/2023] Open
Abstract
Large alterations in transcription accompany neurodegeneration in polyglutamine (polyQ) diseases. These pathologies manifest both general polyQ toxicity and mutant protein-specific effects. In this study, we report that the fat tumour suppressor gene mediates neurodegeneration induced by the polyQ protein Atrophin. We have monitored early transcriptional alterations in a Drosophila model of Dentatorubral-pallidoluysian Atrophy and found that polyQ Atrophins downregulate fat. Fat protects from neurodegeneration and Atrophin toxicity through the Hippo kinase cascade. Fat/Hippo signalling does not provoke neurodegeneration by stimulating overgrowth; rather, it alters the autophagic flux in photoreceptor neurons, thereby affecting cell homeostasis. Our data thus provide a crucial insight into the specific mechanism of a polyQ disease and reveal an unexpected neuroprotective role of the Fat/Hippo pathway.
Collapse
Affiliation(s)
- Francesco Napoletano
- Dulbecco Telethon Institute and Division of Neuroscience, DIBIT-San Raffaele Scientific Institute, Milan, Italy
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Mallik M, Lakhotia SC. Modifiers and mechanisms of multi-system polyglutamine neurodegenerative disorders: lessons from fly models. J Genet 2010; 89:497-526. [DOI: 10.1007/s12041-010-0072-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
43
|
Serão NVL, Veroneze R, Ribeiro AMF, Verardo LL, Braccini Neto J, Gasparino E, Campos CF, Lopes PS, Guimarães SEF. Candidate gene expression and intramuscular fat content in pigs. J Anim Breed Genet 2010; 128:28-34. [PMID: 21214641 DOI: 10.1111/j.1439-0388.2010.00887.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Seventy-two pigs of three genetic groups (Brazilian indigenous breed Piau, Commercial line and Crossbred) of both sexes were slaughtered at four live weights (30, 60, 90 and 120 kg). Intramuscular fat (IMF) content in Longissimus dorsi muscle of each animal was extracted and correlated with candidate gene mRNA expression (ATN1, EEF1A2, FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1). Within slaughter weight of 120 kg, Piau and Crossbred pigs showed higher IMF content (p < 0.05) than commercial animals, with 2.48, 2.08 and 1.00% respectively. Barrows presented higher values of IMF (p < 0.05) than gilts (1.54 and 1.30% respectively). Gene expression of EEF1A2, FABP3, LDLR, OBSCN, PDHB, TRDN and RYR1 were correlated with IMF (p < 0.05) using the whole dataset. For Piau data only, expression of FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1 showed correlation with IMF (p < 0.05). Genes that have important roles in lipid transportation inside the cell (FABP3) and tissues (LDLR) showed correlation with IMF of, respectively, 0.68 and 0.63 using the whole data set, and 0.90 and 0.91 using data from Piau animals. The highly positive correlation of the LDLR and FAPB3 expression with IMF content may confirm that these genes are important for fat deposition in the porcine L. dorsi muscle.
Collapse
Affiliation(s)
- N V L Serão
- Departamento de Zootecnia, Universidade Federal de Viçosa, Viçosa, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Hands SL, Wyttenbach A. Neurotoxic protein oligomerisation associated with polyglutamine diseases. Acta Neuropathol 2010; 120:419-37. [PMID: 20514488 DOI: 10.1007/s00401-010-0703-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 05/20/2010] [Accepted: 05/23/2010] [Indexed: 02/07/2023]
Abstract
Polyglutamine (polyQ) diseases are associated with a CAG/polyQ expansion mutation in unrelated proteins. Upon elongation of the glutamine tract, disease proteins aggregate within cells, mainly in the central nervous system (CNS) and this aggregation process is associated with neurotoxicity. However, it remains unclear to what extent and how this aggregation causes neuronal dysfunction in the CNS. Aiming at preventing neuronal dysfunction, it will be crucial to determine the links between aggregation and cellular dysfunction, understand the folding pathway of polyQ proteins and discover the relative neurotoxicity of polyQ protein species formed along the aggregation pathway. Here, we review what is known about conformations of polyQ peptides and proteins in their monomeric state from experimental and modelling data, how conformational changes of polyQ proteins relate to their oligomerisation and morphology of aggregates and which cellular function are impaired by oligomers, in vitro and in vivo. We also summarise the key modulatory cellular mechanisms and co-factors, which could affect the folding pathway and kinetics of polyQ aggregation. Although many studies have investigated the relationship between polyQ aggregation and toxicity, these have mainly focussed on investigating changes in the formation of the classical hallmark of polyQ diseases, i.e. microscopically visible inclusion bodies. However, recent studies in which oligomeric species have been considered start to shed light on the identity of neurotoxic oligomeric species. Initial evidence suggests that conformational changes induced by polyQ expansions and their surrounding sequence lead to the formation of particular oligomeric intermediates that may differentially affect neurotoxicity.
Collapse
Affiliation(s)
- Sarah L Hands
- Southampton Neuroscience Group, School of Biological Sciences, University of Southampton, Southampton SO16 7PX, UK
| | | |
Collapse
|
45
|
Braid LR, Lee W, Uetrecht AC, Swarup S, Papaianni G, Heiler A, Verheyen EM. Nemo phosphorylates Even-skipped and promotes Eve-mediated repression of odd-skipped in even parasegments during Drosophila embryogenesis. Dev Biol 2010; 343:178-89. [DOI: 10.1016/j.ydbio.2010.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 04/07/2010] [Accepted: 04/07/2010] [Indexed: 11/30/2022]
|
46
|
Nisoli I, Chauvin JP, Napoletano F, Calamita P, Zanin V, Fanto M, Charroux B. Neurodegeneration by polyglutamine Atrophin is not rescued by induction of autophagy. Cell Death Differ 2010; 17:1577-87. [DOI: 10.1038/cdd.2010.31] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
47
|
Yu J, Ying M, Zhuang Y, Xu T, Han M, Wu X, Xu R. C-terminal deletion of the atrophin-1 protein results in growth retardation but not neurodegeneration in mice. Dev Dyn 2010; 238:2471-8. [PMID: 19681162 DOI: 10.1002/dvdy.22063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dentatorubral-pallidoluysian atrophy (DRPLA) is a dominant hereditary neurodegenerative disorder caused by the expansion of a poly-glutamine (poly-Q) repeat in Atrophin-1 protein. Ectopic expression of a poly-Q expanded human Atrophin-1 is sufficient to induce DRPLA phenotypes in mice. However, it is still unclear whether the dominant effect of poly-Q expansion is due to the functional interference with wild-type Atrophin-1 proteins, which exist in both patients and transgenic mice. Here we report the generation and analysis of an Atrophin-1 targeting allele that expresses a truncated protein lacking both the poly-Q repeat and following C-terminal peptides. Homozygous mutants exhibit growth retardation and progressive male infertility, but no obvious signs of neurodegeneration. Moreover, the mutant allele neither blocked nor enhanced the neurodegenerative phenotypes caused by a poly-Q expanded transgene. These results support the model that poly-Q expanded Atrophin-1 proteins cause DRPLA in a manner independent of any functional interaction with wild-type Atrophin-1 proteins.
Collapse
Affiliation(s)
- Juehua Yu
- Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai, China
| | | | | | | | | | | | | |
Collapse
|
48
|
Cellular and Molecular Pathways Triggering Neurodegeneration in the Spinocerebellar Ataxias. THE CEREBELLUM 2009; 9:148-66. [DOI: 10.1007/s12311-009-0144-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
|
49
|
Li W, Kale A, Baker NE. Oriented cell division as a response to cell death and cell competition. Curr Biol 2009; 19:1821-6. [PMID: 19853449 DOI: 10.1016/j.cub.2009.09.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 08/24/2009] [Accepted: 09/03/2009] [Indexed: 10/20/2022]
Abstract
The imaginal disc epithelia that give rise to the adult ectoderm of Drosophila can compensate to produce normal adult organs after damage. We looked at the local response to cell death by using two genetic methods to elevate cell death rates. During cell competition, sporadic cell death occurs predictably along the boundaries between populations of competing wild-type and "Minute" cells (M/+). Boundaries between M/+ and wild-type populations show an unusual degree of mixing, associated with mitotic reorientation of wild-type cells toward M/+ territory that they take over. Apoptosis of M/+ cells was the cue, and reoriented mitosis required the planar cell polarity genes dachsous, fat, and atrophin. Clones mutated for pineapple eye, an essential gene, elevate apoptosis by a noncompetitive mechanism. Mitosis was also reoriented near cells mutant for pineapple eye, likewise dependent on the planar cell polarity genes. These findings show that planar cell polarity genes are required for responses to cell death. Oriented mitosis may help maintain morphology as dividing cells replace those that have been lost.
Collapse
Affiliation(s)
- Wei Li
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | | | | |
Collapse
|
50
|
Garden GA, La Spada AR. Molecular pathogenesis and cellular pathology of spinocerebellar ataxia type 7 neurodegeneration. THE CEREBELLUM 2009; 7:138-49. [PMID: 18418675 DOI: 10.1007/s12311-008-0027-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Spinocerebellar ataxia type 7 (SCA7) is unique among CAG/polyglutamine (polyQ) repeat diseases due to dramatic intergenerational instability in repeat length and an associated cone-rod dystrophy retinal degeneration phenotype. SCA7 is caused by a polyQ expansion in the protein ataxin-7. Like other neurodegenerative diseases caused by polyQ expansion mutations, the spectrum of clinical severity and disease progression worsens with increasing polyQ length. Several potential mechanisms for the molecular pathogenesis of polyQ-expanded ataxin-7 have been suggested. These include, but are not limited to, alteration of endogenous ataxin-7 function, abnormal processing and stability of polyQ ataxin-7, and alteration of transcriptional regulation via interaction of polyQ-expanded ataxin-7 with other transcriptional regulators. Ataxin-7's normal function as a transcription factor may contribute to the selective vulnerability of specific cellular populations in SCA7, and the resolution of the mechanistic basis of this pathogenic cascade is a major focus of SCA7 disease research. PolyQ-expanded ataxin-7 can cause non-cell autonomous neurodegeneration in cerebellar Purkinje cells. Advances in understanding SCA7's molecular basis have led to important insights into cell-type specific neurodegeneration. We expect that further study of ataxin-7 normal function, insights into the molecular basis of SCA7 neurodegeneration, and the development of therapeutic interventions for SCA7 will greatly influence related endeavors directed at other CAG/polyQ repeat diseases.
Collapse
Affiliation(s)
- Gwenn A Garden
- Department of Neurology, University of Washington, Seattle, Washington 98195-7110, USA
| | | |
Collapse
|