1
|
Diaz LR, Gil-Ranedo J, Jaworek KJ, Nsek N, Marques JP, Costa E, Hilton DA, Bieluczyk H, Warrington O, Hanemann CO, Futschik ME, Bossing T, Barros CS. Ribogenesis boosts controlled by HEATR1-MYC interplay promote transition into brain tumour growth. EMBO Rep 2024; 25:168-197. [PMID: 38225354 PMCID: PMC10897169 DOI: 10.1038/s44319-023-00017-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 01/17/2024] Open
Abstract
Cell commitment to tumourigenesis and the onset of uncontrolled growth are critical determinants in cancer development but the early events directing tumour initiating cell (TIC) fate remain unclear. We reveal a single-cell transcriptome profile of brain TICs transitioning into tumour growth using the brain tumour (brat) neural stem cell-based Drosophila model. Prominent changes in metabolic and proteostasis-associated processes including ribogenesis are identified. Increased ribogenesis is a known cell adaptation in established tumours. Here we propose that brain TICs boost ribogenesis prior to tumour growth. In brat-deficient TICs, we show that this dramatic change is mediated by upregulated HEAT-Repeat Containing 1 (HEATR1) to promote ribosomal RNA generation, TIC enlargement and onset of overgrowth. High HEATR1 expression correlates with poor glioma patient survival and patient-derived glioblastoma stem cells rely on HEATR1 for enhanced ribogenesis and tumourigenic potential. Finally, we show that HEATR1 binds the master growth regulator MYC, promotes its nucleolar localisation and appears required for MYC-driven ribogenesis, suggesting a mechanism co-opted in ribogenesis reprogramming during early brain TIC development.
Collapse
Affiliation(s)
- Laura R Diaz
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Jon Gil-Ranedo
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Karolina J Jaworek
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
- School of Biological Sciences, Bangor University, LL57 2UW, Bangor, UK
| | - Nsikan Nsek
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Joao Pinheiro Marques
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Eleni Costa
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - David A Hilton
- Department of Cellular and Anatomical Pathology, University Hospitals Plymouth, PL6 8DH, Plymouth, UK
| | - Hubert Bieluczyk
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Oliver Warrington
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, WC1N 3AR, London, UK
| | - C Oliver Hanemann
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Matthias E Futschik
- School of Biomedical Sciences, Faculty of Health, Derriford Research Facility, University of Plymouth, PL6 8BU, Plymouth, UK
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504, Coimbra, Portugal
| | - Torsten Bossing
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Claudia S Barros
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK.
| |
Collapse
|
2
|
Dudley-Fraser J, Rittinger K. It's a TRIM-endous view from the top: the varied roles of TRIpartite Motif proteins in brain development and disease. Front Mol Neurosci 2023; 16:1287257. [PMID: 38115822 PMCID: PMC10728303 DOI: 10.3389/fnmol.2023.1287257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 11/13/2023] [Indexed: 12/21/2023] Open
Abstract
The tripartite motif (TRIM) protein family members have been implicated in a multitude of physiologies and pathologies in different tissues. With diverse functions in cellular processes including regulation of signaling pathways, protein degradation, and transcriptional control, the impact of TRIM dysregulation can be multifaceted and complex. Here, we focus on the cellular and molecular roles of TRIMs identified in the brain in the context of a selection of pathologies including cancer and neurodegeneration. By examining each disease in parallel with described roles in brain development, we aim to highlight fundamental common mechanisms employed by TRIM proteins and identify opportunities for therapeutic intervention.
Collapse
Affiliation(s)
- Jane Dudley-Fraser
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Katrin Rittinger
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, London, United Kingdom
| |
Collapse
|
3
|
Abidi SNF, Hsu FTY, Smith-Bolton RK. Regenerative growth is constrained by brain tumor to ensure proper patterning in Drosophila. PLoS Genet 2023; 19:e1011103. [PMID: 38127821 PMCID: PMC10769103 DOI: 10.1371/journal.pgen.1011103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 01/05/2024] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Some animals respond to injury by inducing new growth to regenerate the lost structures. This regenerative growth must be carefully controlled and constrained to prevent aberrant growth and to allow correct organization of the regenerating tissue. However, the factors that restrict regenerative growth have not been identified. Using a genetic ablation system in the Drosophila wing imaginal disc, we have identified one mechanism that constrains regenerative growth, impairment of which also leads to erroneous patterning of the final appendage. Regenerating discs with reduced levels of the RNA-regulator Brain tumor (Brat) exhibit enhanced regeneration, but produce adult wings with disrupted margins that are missing extensive tracts of sensory bristles. In these mutants, aberrantly high expression of the pro-growth factor Myc and its downstream targets likely contributes to this loss of cell-fate specification. Thus, Brat constrains the expression of pro-regeneration genes and ensures that the regenerating tissue forms the proper final structure.
Collapse
Affiliation(s)
- Syeda Nayab Fatima Abidi
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Felicity Ting-Yu Hsu
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Rachel K. Smith-Bolton
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Carle R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| |
Collapse
|
4
|
Rajan A, Anhezini L, Rives-Quinto N, Chhabra JY, Neville MC, Larson ED, Goodwin SF, Harrison MM, Lee CY. Low-level repressive histone marks fine-tune gene transcription in neural stem cells. eLife 2023; 12:e86127. [PMID: 37314324 PMCID: PMC10344426 DOI: 10.7554/elife.86127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 06/11/2023] [Indexed: 06/15/2023] Open
Abstract
Coordinated regulation of gene activity by transcriptional and translational mechanisms poise stem cells for a timely cell-state transition during differentiation. Although important for all stemness-to-differentiation transitions, mechanistic understanding of the fine-tuning of gene transcription is lacking due to the compensatory effect of translational control. We used intermediate neural progenitor (INP) identity commitment to define the mechanisms that fine-tune stemness gene transcription in fly neural stem cells (neuroblasts). We demonstrate that the transcription factor FruitlessC (FruC) binds cis-regulatory elements of most genes uniquely transcribed in neuroblasts. Loss of fruC function alone has no effect on INP commitment but drives INP dedifferentiation when translational control is reduced. FruC negatively regulates gene expression by promoting low-level enrichment of the repressive histone mark H3K27me3 in gene cis-regulatory regions. Identical to fruC loss-of-function, reducing Polycomb Repressive Complex 2 activity increases stemness gene activity. We propose low-level H3K27me3 enrichment fine-tunes gene transcription in stem cells, a mechanism likely conserved from flies to humans.
Collapse
Affiliation(s)
- Arjun Rajan
- Life Sciences Institute, University of Michigan-Ann ArborAnn ArborUnited States
| | - Lucas Anhezini
- Life Sciences Institute, University of Michigan-Ann ArborAnn ArborUnited States
| | - Noemi Rives-Quinto
- Life Sciences Institute, University of Michigan-Ann ArborAnn ArborUnited States
| | - Jay Y Chhabra
- Life Sciences Institute, University of Michigan-Ann ArborAnn ArborUnited States
| | - Megan C Neville
- Centre for Neural Circuits and Behaviour, University of OxfordOxfordUnited Kingdom
| | - Elizabeth D Larson
- Department of Biomolecular Chemistry, University of Wisconsin-MadisonMadisonUnited States
| | - Stephen F Goodwin
- Centre for Neural Circuits and Behaviour, University of OxfordOxfordUnited Kingdom
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, University of Wisconsin-MadisonMadisonUnited States
| | - Cheng-Yu Lee
- Life Sciences Institute, University of Michigan-Ann ArborAnn ArborUnited States
- Department of Cell and Developmental Biology, University of Michigan Medical SchoolAnn ArborUnited States
- Division of Genetic Medicine, Department of Internal Medicine, University of Michigan Medical SchoolAnn ArborUnited States
- Rogel Cancer Center, University of Michigan Medical SchoolAnn ArborUnited States
| |
Collapse
|
5
|
Sharpe JL, Morgan J, Nisbet N, Campbell K, Casali A. Modelling Cancer Metastasis in Drosophila melanogaster. Cells 2023; 12:cells12050677. [PMID: 36899813 PMCID: PMC10000390 DOI: 10.3390/cells12050677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/14/2023] [Accepted: 02/17/2023] [Indexed: 02/24/2023] Open
Abstract
Cancer metastasis, the process by which tumour cells spread throughout the body and form secondary tumours at distant sites, is the leading cause of cancer-related deaths. The metastatic cascade is a highly complex process encompassing initial dissemination from the primary tumour, travel through the blood stream or lymphatic system, and the colonisation of distant organs. However, the factors enabling cells to survive this stressful process and adapt to new microenvironments are not fully characterised. Drosophila have proven a powerful system in which to study this process, despite important caveats such as their open circulatory system and lack of adaptive immune system. Historically, larvae have been used to model cancer due to the presence of pools of proliferating cells in which tumours can be induced, and transplanting these larval tumours into adult hosts has enabled tumour growth to be monitored over longer periods. More recently, thanks largely to the discovery that there are stem cells in the adult midgut, adult models have been developed. We focus this review on the development of different Drosophila models of metastasis and how they have contributed to our understanding of important factors determining metastatic potential, including signalling pathways, the immune system and the microenvironment.
Collapse
Affiliation(s)
- Joanne L. Sharpe
- School of Biosciences, The University of Sheffield, Sheffield S10 2TN, UK
| | - Jason Morgan
- School of Biosciences, The University of Sheffield, Sheffield S10 2TN, UK
| | - Nicholas Nisbet
- School of Biosciences, The University of Sheffield, Sheffield S10 2TN, UK
| | - Kyra Campbell
- School of Biosciences, The University of Sheffield, Sheffield S10 2TN, UK
- Correspondence: (K.C.); (A.C.)
| | - Andreu Casali
- Departament de Ciències Mèdiques Bàsiques, Universitat de Lleida and IRBLleida, Av. Alcalde Rovira Roure, 80, 25198 Lleida, Spain
- Correspondence: (K.C.); (A.C.)
| |
Collapse
|
6
|
Larson ED, Komori H, Fitzpatrick ZA, Krabbenhoft SD, Lee CY, Harrison M. Premature translation of the Drosophila zygotic genome activator Zelda is not sufficient to precociously activate gene expression. G3 (BETHESDA, MD.) 2022; 12:6649735. [PMID: 35876878 PMCID: PMC9434156 DOI: 10.1093/g3journal/jkac159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 06/15/2022] [Indexed: 05/22/2023]
Abstract
Following fertilization, the unified germ cells rapidly transition to a totipotent embryo. Maternally deposited mRNAs encode the proteins necessary for this reprogramming as the zygotic genome remains transcriptionally quiescent during the initial stages of development. The transcription factors required to activate the zygotic genome are among these maternally deposited mRNAs and are robustly translated following fertilization. In Drosophila, the mRNA encoding Zelda, the major activator of the zygotic genome, is not translated until 1 h after fertilization. Here we demonstrate that zelda translation is repressed in the early embryo by the TRIM-NHL protein Brain tumor (BRAT). BRAT also regulates Zelda levels in the larval neuroblast lineage. In the embryo, BRAT-mediated translational repression is regulated by the Pan Gu kinase, which is triggered by egg activation. The Pan Gu kinase phosphorylates translational regulators, suggesting that Pan Gu kinase activity alleviates translational repression of zelda by BRAT and coupling translation of zelda with that of other regulators of early embryonic development. Using the premature translation of zelda in embryos lacking BRAT activity, we showed that early translation of a zygotic genome activator is not sufficient to drive precocious gene expression. Instead, Zelda-target genes showed increased expression at the time they are normally activated. We propose that transition through early development requires the integration of multiple processes, including the slowing of the nuclear division cycle and activation of the zygotic genome. These processes are coordinately controlled by Pan Gu kinase-mediated regulation of translation.
Collapse
Affiliation(s)
- Elizabeth D Larson
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Hideyuki Komori
- Department of Cell and Developmental Biology and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Zoe A Fitzpatrick
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Samuel D Krabbenhoft
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Cheng-Yu Lee
- Department of Cell and Developmental Biology and Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Melissa Harrison
- Corresponding author: Department of Biomolecular Chemistry, University of Wisconsin-Madison, 440 Henry Mall, 6204B Biochemical Sciences Building, Madison, WI 53706, USA.
| |
Collapse
|
7
|
Zhang L, Zhang S, Wang R, Sun L. Genome-Wide Identification of Long Noncoding RNA and Their Potential Interactors in ISWI Mutants. Int J Mol Sci 2022; 23:ijms23116247. [PMID: 35682924 PMCID: PMC9181106 DOI: 10.3390/ijms23116247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/28/2022] [Accepted: 05/31/2022] [Indexed: 11/17/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) have been identified as key regulators of gene expression and participate in many vital physiological processes. Chromatin remodeling, being an important epigenetic modification, has been identified in many biological activities as well. However, the regulatory mechanism of lncRNA in chromatin remodeling remains unclear. In order to characterize the genome-wide lncRNA expression and their potential interacting factors during this process in Drosophila, we investigated the expression pattern of lncRNAs and mRNAs based on the transcriptome analyses and found significant differences between lncRNAs and mRNAs. Then, we performed TSA-FISH experiments of candidate lncRNAs and their potential interactors that have different functions in Drosophila embryos to determine their expression pattern. In addition, we also analyzed the expression of transposable elements (TEs) and their interactors to explore their expression in ISWI mutants. Our results provide a new perspective for understanding the possible regulatory mechanism of lncRNAs and TEs as well as their targets in chromatin remodeling.
Collapse
|
8
|
Salerno-Kochan A, Horn A, Ghosh P, Nithin C, Kościelniak A, Meindl A, Strauss D, Krutyhołowa R, Rossbach O, Bujnicki JM, Gaik M, Medenbach J, Glatt S. Molecular insights into RNA recognition and gene regulation by the TRIM-NHL protein Mei-P26. Life Sci Alliance 2022; 5:5/8/e202201418. [PMID: 35512835 PMCID: PMC9070667 DOI: 10.26508/lsa.202201418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 02/06/2023] Open
Abstract
The TRIM-NHL protein Meiotic P26 (Mei-P26) acts as a regulator of cell fate in Drosophila Its activity is critical for ovarian germline stem cell maintenance, differentiation of oocytes, and spermatogenesis. Mei-P26 functions as a post-transcriptional regulator of gene expression; however, the molecular details of how its NHL domain selectively recognizes and regulates its mRNA targets have remained elusive. Here, we present the crystal structure of the Mei-P26 NHL domain at 1.6 Å resolution and identify key amino acids that confer substrate specificity and distinguish Mei-P26 from closely related TRIM-NHL proteins. Furthermore, we identify mRNA targets of Mei-P26 in cultured Drosophila cells and show that Mei-P26 can act as either a repressor or activator of gene expression on different RNA targets. Our work reveals the molecular basis of RNA recognition by Mei-P26 and the fundamental functional differences between otherwise very similar TRIM-NHL proteins.
Collapse
Affiliation(s)
- Anna Salerno-Kochan
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.,Postgraduate School of Molecular Medicine, Warsaw, Poland
| | - Andreas Horn
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Pritha Ghosh
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Chandran Nithin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Anna Kościelniak
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Andreas Meindl
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Daniela Strauss
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | | | - Oliver Rossbach
- Institute of Biochemistry, University of Giessen, Giessen, Germany
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw, Poland.,Bioinformatics Laboratory, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznan, Poland
| | - Monika Gaik
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| | - Jan Medenbach
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Sebastian Glatt
- Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland
| |
Collapse
|
9
|
Larson ED, Komori H, Gibson TJ, Ostgaard CM, Hamm DC, Schnell JM, Lee CY, Harrison MM. Cell-type-specific chromatin occupancy by the pioneer factor Zelda drives key developmental transitions in Drosophila. Nat Commun 2021; 12:7153. [PMID: 34887421 PMCID: PMC8660810 DOI: 10.1038/s41467-021-27506-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 11/24/2021] [Indexed: 12/14/2022] Open
Abstract
During Drosophila embryogenesis, the essential pioneer factor Zelda defines hundreds of cis-regulatory regions and in doing so reprograms the zygotic transcriptome. While Zelda is essential later in development, it is unclear how the ability of Zelda to define cis-regulatory regions is shaped by cell-type-specific chromatin architecture. Asymmetric division of neural stem cells (neuroblasts) in the fly brain provide an excellent paradigm for investigating the cell-type-specific functions of this pioneer factor. We show that Zelda synergistically functions with Notch to maintain neuroblasts in an undifferentiated state. Zelda misexpression reprograms progenitor cells to neuroblasts, but this capacity is limited by transcriptional repressors critical for progenitor commitment. Zelda genomic occupancy in neuroblasts is reorganized as compared to the embryo, and this reorganization is correlated with differences in chromatin accessibility and cofactor availability. We propose that Zelda regulates essential transitions in the neuroblasts and embryo through a shared gene-regulatory network driven by cell-type-specific enhancers.
Collapse
Affiliation(s)
- Elizabeth D Larson
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Hideyuki Komori
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Tyler J Gibson
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Cyrina M Ostgaard
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Danielle C Hamm
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Jack M Schnell
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Stem Cell and Regenerative Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Cheng-Yu Lee
- Division of Genetic Medicine, Department of Internal Medicine and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Melissa M Harrison
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
| |
Collapse
|
10
|
Macošek J, Simon B, Linse JB, Jagtap PKA, Winter SL, Foot J, Lapouge K, Perez K, Rettel M, Ivanović MT, Masiewicz P, Murciano B, Savitski MM, Loedige I, Hub JS, Gabel F, Hennig J. Structure and dynamics of the quaternary hunchback mRNA translation repression complex. Nucleic Acids Res 2021; 49:8866-8885. [PMID: 34329466 PMCID: PMC8421216 DOI: 10.1093/nar/gkab635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/05/2021] [Accepted: 07/27/2021] [Indexed: 01/02/2023] Open
Abstract
A key regulatory process during Drosophila development is the localized suppression of the hunchback mRNA translation at the posterior, which gives rise to a hunchback gradient governing the formation of the anterior-posterior body axis. This suppression is achieved by a concerted action of Brain Tumour (Brat), Pumilio (Pum) and Nanos. Each protein is necessary for proper Drosophila development. The RNA contacts have been elucidated for the proteins individually in several atomic-resolution structures. However, the interplay of all three proteins during RNA suppression remains a long-standing open question. Here, we characterize the quaternary complex of the RNA-binding domains of Brat, Pum and Nanos with hunchback mRNA by combining NMR spectroscopy, SANS/SAXS, XL/MS with MD simulations and ITC assays. The quaternary hunchback mRNA suppression complex comprising the RNA binding domains is flexible with unoccupied nucleotides functioning as a flexible linker between the Brat and Pum-Nanos moieties of the complex. Moreover, the presence of the Pum-HD/Nanos-ZnF complex has no effect on the equilibrium RNA binding affinity of the Brat RNA binding domain. This is in accordance with previous studies, which showed that Brat can suppress mRNA independently and is distributed uniformly throughout the embryo.
Collapse
Affiliation(s)
- Jakub Macošek
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Bernd Simon
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Johanna-Barbara Linse
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Pravin Kumar Ankush Jagtap
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Sophie L Winter
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Jaelle Foot
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Karine Lapouge
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Kathryn Perez
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Mandy Rettel
- Proteomics Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Miloš T Ivanović
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Pawel Masiewicz
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Brice Murciano
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Mikhail M Savitski
- Proteomics Core Facility, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Inga Loedige
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany
| | - Jochen S Hub
- Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken 66123, Germany
| | - Frank Gabel
- Institut Biologie Structurale, University Grenoble Alpes, CEA, CNRS, Grenoble 38044, France
| | - Janosch Hennig
- Structural and Computational Biology Unit, European Molecular Biology Laboratory Heidelberg, Heidelberg 69117, Germany.,Chair of Biochemistry IV, Biophysical Chemistry, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| |
Collapse
|
11
|
Climent-Cantó P, Carbonell A, Tamirisa S, Henn L, Pérez-Montero S, Boros IM, Azorín F. The tumour suppressor brain tumour (Brat) regulates linker histone dBigH1 expression in the Drosophila female germline and the early embryo. Open Biol 2021; 11:200408. [PMID: 33947246 PMCID: PMC8097206 DOI: 10.1098/rsob.200408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Linker histones H1 are essential chromatin components that exist as multiple developmentally regulated variants. In metazoans, specific H1s are expressed during germline development in a tightly regulated manner. However, the mechanisms governing their stage-dependent expression are poorly understood. Here, we address this question in Drosophila, which encodes for a single germline-specific dBigH1 linker histone. We show that during female germline lineage differentiation, dBigH1 is expressed in germ stem cells and cystoblasts, becomes silenced during transit-amplifying (TA) cystocytes divisions to resume expression after proliferation stops and differentiation starts, when it progressively accumulates in the oocyte. We find that dBigH1 silencing during TA divisions is post-transcriptional and depends on the tumour suppressor Brain tumour (Brat), an essential RNA-binding protein that regulates mRNA translation and stability. Like other oocyte-specific variants, dBigH1 is maternally expressed during early embryogenesis until it is replaced by somatic dH1 at the maternal-to-zygotic transition (MZT). Brat also mediates dBigH1 silencing at MZT. Finally, we discuss the situation in testes, where Brat is not expressed, but dBigH1 is translationally silenced too.
Collapse
Affiliation(s)
- Paula Climent-Cantó
- Institute of Molecular Biology of Barcelona, CSIC, Barcelona 08028, Spain.,Institute for Research in Biomedicine, IRB Barcelona, The Barcelona Institute for Science and Technology, Barcelona 08028, Spain
| | - Albert Carbonell
- Institute of Molecular Biology of Barcelona, CSIC, Barcelona 08028, Spain.,Institute for Research in Biomedicine, IRB Barcelona, The Barcelona Institute for Science and Technology, Barcelona 08028, Spain
| | - Srividya Tamirisa
- Institute of Molecular Biology of Barcelona, CSIC, Barcelona 08028, Spain.,Institute for Research in Biomedicine, IRB Barcelona, The Barcelona Institute for Science and Technology, Barcelona 08028, Spain
| | - Laszlo Henn
- Institute of Biochemistry, Biological Research Centre of Szeged, Szeged 6726, Hungary
| | - Salvador Pérez-Montero
- Institute of Molecular Biology of Barcelona, CSIC, Barcelona 08028, Spain.,Institute for Research in Biomedicine, IRB Barcelona, The Barcelona Institute for Science and Technology, Barcelona 08028, Spain
| | - Imre M Boros
- Institute of Biochemistry, Biological Research Centre of Szeged, Szeged 6726, Hungary.,Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged 6726, Hungary
| | - Fernando Azorín
- Institute of Molecular Biology of Barcelona, CSIC, Barcelona 08028, Spain.,Institute for Research in Biomedicine, IRB Barcelona, The Barcelona Institute for Science and Technology, Barcelona 08028, Spain
| |
Collapse
|
12
|
Goyani S, Roy M, Singh R. TRIM-NHL as RNA Binding Ubiquitin E3 Ligase (RBUL): Implication in development and disease pathogenesis. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166066. [PMID: 33418035 DOI: 10.1016/j.bbadis.2020.166066] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 12/14/2020] [Accepted: 12/27/2020] [Indexed: 12/20/2022]
Abstract
TRIM proteins are RING domain-containing modular ubiquitin ligases, unique due to their stimuli specific expression, localization, and turnover. The TRIM family consists of more than 76 proteins, including the TRIM-NHL sub-family which possesses RNA binding ability along with the inherent E3 Ligase activity, hence can be classified as a unique class of RNA Binding Ubiquitin Ligases (RBULs). Having these two abilities, TRIM-NHL proteins can play important role in a wide variety of cellular processes and their dysregulation can lead to complex and systemic pathological conditions. Increasing evidence suggests that TRIM-NHL proteins regulate RNA at the transcriptional and post-transcriptional level having implications in differentiation, development, and many pathological conditions. This review explores the evolving role of TRIM-NHL proteins as TRIM-RBULs, their ubiquitin ligase and RNA binding ability regulating cellular processes, and their possible role in different pathophysiological conditions.
Collapse
Affiliation(s)
- Shanikumar Goyani
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India
| | - Milton Roy
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India
| | - Rajesh Singh
- Department of Biochemistry, Faculty of Science, The M.S. University of Baroda, Vadodara 390 002, Gujarat, India.
| |
Collapse
|
13
|
MYC in Brain Development and Cancer. Int J Mol Sci 2020; 21:ijms21207742. [PMID: 33092025 PMCID: PMC7588885 DOI: 10.3390/ijms21207742] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/16/2020] [Accepted: 10/16/2020] [Indexed: 12/27/2022] Open
Abstract
The MYC family of transcriptional regulators play significant roles in animal development, including the renewal and maintenance of stem cells. Not surprisingly, given MYC's capacity to promote programs of proliferative cell growth, MYC is frequently upregulated in cancer. Although members of the MYC family are upregulated in nervous system tumours, the mechanisms of how elevated MYC promotes stem cell-driven brain cancers is unknown. If we are to determine how increased MYC might contribute to brain cancer progression, we will require a more complete understanding of MYC's roles during normal brain development. Here, we evaluate evidence for MYC family functions in neural stem cell fate and brain development, with a view to better understand mechanisms of MYC-driven neural malignancies.
Collapse
|
14
|
Kulkarni A, Lopez DH, Extavour CG. Shared Cell Biological Functions May Underlie Pleiotropy of Molecular Interactions in the Germ Lines and Nervous Systems of Animals. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|
15
|
Connacher RP, Goldstrohm AC. Molecular and biological functions of TRIM-NHL RNA-binding proteins. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1620. [PMID: 32738036 DOI: 10.1002/wrna.1620] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 01/02/2023]
Abstract
The TRIM-NHL family of proteins shares a conserved domain architecture and play crucial roles in stem cell biology, fertility, and development. This review synthesizes new insights that have revolutionized our understanding of the molecular and biological functions of TRIM-NHL proteins. Multiple TRIM-NHLs have been shown to bind specific RNA sequences and structures. X-ray crystal structures of TRIM-NHL proteins in complex with RNA ligands reveal versatile modes of RNA recognition by the NHL domain. Functional and genetic analyses show that TRIM-NHL RNA-binding proteins negatively regulate the protein expression from the target mRNAs that they bind. This repressive activity plays a crucial role in controlling stem cell fate in the developing brain and differentiating germline. To highlight these paradigms, we focus on several of the most-extensively studied TRIM-NHL proteins, specifically Drosophila and vertebrate TRIM71, among others. Brat is essential for development and regulates key target mRNAs to control differentiation of germline and neural stem cells. TRIM71 is also required for development and promotes stem cell proliferation while antagonizing differentiation. Moreover, TRIM71 can be utilized to help reprogram fibroblasts into induced pluripotent stem cells. Recently discovered mutations in TRIM71 cause the neurodevelopmental disease congenital hydrocephalus and emphasize the importance of its RNA-binding function in brain development. Further relevance of TRIM71 to disease pathogenesis comes from evidence linking it to several types of cancer, including liver and testicular cancer. Collectively, these advances demonstrate a primary role for TRIM-NHL proteins in the post-transcriptional regulation of gene expression in crucial biological processes. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications Translation > Translation Regulation RNA Turnover and Surveillance > Regulation of RNA Stability.
Collapse
Affiliation(s)
- Robert P Connacher
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | | |
Collapse
|
16
|
Keegan SE, Hughes SC. Role of nuclear-cytoplasmic protein localization during Drosophila neuroblast development. Genome 2020; 64:75-85. [PMID: 32526151 DOI: 10.1139/gen-2020-0039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nuclear-cytoplasmic localization is an efficient way to regulate transcription factors and chromatin remodelers. Altering the location of existing protein pools also facilitates a more rapid response to changes in cell activity or extracellular signals. There are several examples of proteins that are regulated by nucleo-cytoplasmic shuttling, which are required for Drosophila neuroblast development. Disruption of the localization of homologs of these proteins has also been linked to several neurodegenerative disorders in humans. Drosophila has been used extensively to model the neurodegenerative disorders caused by aberrant nucleo-cytoplasmic localization. Here, we focus on the role of alternative nucleo-cytoplasmic protein localization in regulating proliferation and cell fate decisions in the Drosophila neuroblast and in neurodegenerative disorders. We also explore the analogous role of RNA binding proteins and mRNA localization in the context of regulation of nucleo-cytoplasmic localization during neural development and a role in neurodegenerative disorders.
Collapse
Affiliation(s)
- Sophie E Keegan
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Sarah C Hughes
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
17
|
Williams FP, Haubrich K, Perez-Borrajero C, Hennig J. Emerging RNA-binding roles in the TRIM family of ubiquitin ligases. Biol Chem 2020; 400:1443-1464. [PMID: 31120853 DOI: 10.1515/hsz-2019-0158] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/11/2019] [Indexed: 12/14/2022]
Abstract
TRIM proteins constitute a large, diverse and ancient protein family which play a key role in processes including cellular differentiation, autophagy, apoptosis, DNA repair, and tumour suppression. Mostly known and studied through the lens of their ubiquitination activity as E3 ligases, it has recently emerged that many of these proteins are involved in direct RNA binding through their NHL or PRY/SPRY domains. We summarise the current knowledge concerning the mechanism of RNA binding by TRIM proteins and its biological role. We discuss how RNA-binding relates to their previously described functions such as E3 ubiquitin ligase activity, and we will consider the potential role of enrichment in membrane-less organelles.
Collapse
Affiliation(s)
- Felix Preston Williams
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Kevin Haubrich
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Cecilia Perez-Borrajero
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Janosch Hennig
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany, e-mail:
| |
Collapse
|
18
|
Bawa S, Brooks DS, Neville KE, Tipping M, Sagar MA, Kollhoff JA, Chawla G, Geisbrecht BV, Tennessen JM, Eliceiri KW, Geisbrecht ER. Drosophila TRIM32 cooperates with glycolytic enzymes to promote cell growth. eLife 2020; 9:52358. [PMID: 32223900 PMCID: PMC7105379 DOI: 10.7554/elife.52358] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 03/23/2020] [Indexed: 12/13/2022] Open
Abstract
Cell growth and/or proliferation may require the reprogramming of metabolic pathways, whereby a switch from oxidative to glycolytic metabolism diverts glycolytic intermediates towards anabolic pathways. Herein, we identify a novel role for TRIM32 in the maintenance of glycolytic flux mediated by biochemical interactions with the glycolytic enzymes Aldolase and Phosphoglycerate mutase. Loss of Drosophila TRIM32, encoded by thin (tn), shows reduced levels of glycolytic intermediates and amino acids. This altered metabolic profile correlates with a reduction in the size of glycolytic larval muscle and brain tissue. Consistent with a role for metabolic intermediates in glycolysis-driven biomass production, dietary amino acid supplementation in tn mutants improves muscle mass. Remarkably, TRIM32 is also required for ectopic growth - loss of TRIM32 in a wing disc-associated tumor model reduces glycolytic metabolism and restricts growth. Overall, our results reveal a novel role for TRIM32 for controlling glycolysis in the context of both normal development and tumor growth.
Collapse
Affiliation(s)
- Simranjot Bawa
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, United States
| | - David S Brooks
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, United States
| | - Kathryn E Neville
- Department of Biology, Providence College, Providence, United States
| | - Marla Tipping
- Department of Biology, Providence College, Providence, United States
| | - Md Abdul Sagar
- Laboratory for Optical and Computational Instrumentation, Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, United States
| | - Joseph A Kollhoff
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, United States
| | - Geetanjali Chawla
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, India.,Department of Biology, Indiana University, Bloomington, United States
| | - Brian V Geisbrecht
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, United States
| | - Jason M Tennessen
- Department of Biology, Indiana University, Bloomington, United States
| | - Kevin W Eliceiri
- Laboratory for Optical and Computational Instrumentation, Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, United States
| | - Erika R Geisbrecht
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, United States
| |
Collapse
|
19
|
Rastegari E, Kajal K, Tan BS, Huang F, Chen RH, Hsieh TS, Hsu HJ. WD40 protein Wuho controls germline homeostasis via TRIM-NHL tumor suppressor Mei-p26 in Drosophila. Development 2020; 147:147/2/dev182063. [PMID: 31941704 DOI: 10.1242/dev.182063] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 12/03/2019] [Indexed: 12/22/2022]
Abstract
WD40 proteins control many cellular processes via protein interactions. Drosophila Wuho (Wh, a WD40 protein) controls fertility, although the involved mechanisms are unclear. Here, we show that Wh promotion of Mei-p26 (a human TRIM32 ortholog) function maintains ovarian germ cell homeostasis. Wh and Mei-p26 are epistatically linked, with wh and mei-p26 mutants showing nearly identical phenotypes, including germline stem cell (GSC) loss, stem-cyst formation due to incomplete cytokinesis between GSCs and daughter cells, and overproliferation of GSC progeny. Mechanistically, Wh interacts with Mei-p26 in different cellular contexts to induce cell type-specific effects. In GSCs, Wh and Mei-p26 promote BMP stemness signaling for proper GSC division and maintenance. In GSC progeny, Wh and Mei-p26 silence nanos translation, downregulate a subset of microRNAs involved in germ cell differentiation and suppress ribosomal biogenesis via dMyc to limit germ cell mitosis. We also found that the human ortholog of Wh (WDR4) interacts with TRIM32 in human cells. Our results show that Wh is a regulator of Mei-p26 in Drosophila germ cells and suggest that the WD40-TRIM interaction may also control tissue homeostasis in other stem cell systems.
Collapse
Affiliation(s)
- Elham Rastegari
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan, R.O.C.,Graduate Institute of Life Science, National Defense Medical Center, Taipei 11490, Taiwan, R.O.C.,Institute of Cellular and Organismic Biology, Sinica, Taipei 11529, Taiwan, R.O.C
| | - Kreeti Kajal
- Institute of Cellular and Organismic Biology, Sinica, Taipei 11529, Taiwan, R.O.C.,Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529, Taiwan, R.O.C.,Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan, R.O.C
| | - Boon-Shing Tan
- Institute of Biological Chemistry, Sinica, Taipei 11529, Taiwan, R.O.C
| | - Fu Huang
- Institute of Biological Chemistry, Sinica, Taipei 11529, Taiwan, R.O.C
| | - Ruey-Hwa Chen
- Institute of Biological Chemistry, Sinica, Taipei 11529, Taiwan, R.O.C
| | - Tao-Shieh Hsieh
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan, R.O.C.,Graduate Institute of Life Science, National Defense Medical Center, Taipei 11490, Taiwan, R.O.C.,Institute of Cellular and Organismic Biology, Sinica, Taipei 11529, Taiwan, R.O.C
| | - Hwei-Jan Hsu
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan, R.O.C .,Graduate Institute of Life Science, National Defense Medical Center, Taipei 11490, Taiwan, R.O.C.,Institute of Cellular and Organismic Biology, Sinica, Taipei 11529, Taiwan, R.O.C.,Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529, Taiwan, R.O.C.,Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan, R.O.C
| |
Collapse
|
20
|
Abdusselamoglu MD, Landskron L, Bowman SK, Eroglu E, Burkard T, Kingston RE, Knoblich JA. Dynamics of activating and repressive histone modifications in Drosophila neural stem cell lineages and brain tumors. Development 2019; 146:dev.183400. [PMID: 31748204 DOI: 10.1242/dev.183400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/12/2019] [Indexed: 12/21/2022]
Abstract
During central nervous system development, spatiotemporal gene expression programs mediate specific lineage decisions to generate neuronal and glial cell types from neural stem cells (NSCs). However, little is known about the epigenetic landscape underlying these highly complex developmental events. Here, we perform ChIP-seq on distinct subtypes of Drosophila FACS-purified NSCs and their differentiated progeny to dissect the epigenetic changes accompanying the major lineage decisions in vivo By analyzing active and repressive histone modifications, we show that stem cell identity genes are silenced during differentiation by loss of their activating marks and not via repressive histone modifications. Our analysis also uncovers a new set of genes specifically required for altering lineage patterns in type II neuroblasts (NBs), one of the two main Drosophila NSC identities. Finally, we demonstrate that this subtype specification in NBs, unlike NSC differentiation, requires Polycomb-group-mediated repression.
Collapse
Affiliation(s)
- Merve Deniz Abdusselamoglu
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Lisa Landskron
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Sarah K Bowman
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Elif Eroglu
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Thomas Burkard
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Robert E Kingston
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Jürgen A Knoblich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| |
Collapse
|
21
|
Liu C, Shan Z, Diao J, Wen W, Wang W. Crystal structure of the coiled‐coil domain of
Drosophila
TRIM protein Brat. Proteins 2019; 87:706-710. [DOI: 10.1002/prot.25691] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/01/2019] [Accepted: 04/04/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Chunhua Liu
- Department of ChemistryInstitutes of Biomedical Sciences and Multiscale Research Institute of Complex System, Fudan University Shanghai People's Republic of China
| | - Zelin Shan
- Department of NeurosurgeryHuashan Hospital, Institutes of Biomedical Sciences, State Key Laboratory of Medical Neurobiology, Shanghai Medical College of Fudan University Shanghai People's Republic of China
- Department of Systems Biology for MedicineSchool of Basic Medical Sciences, Shanghai Medical College of Fudan University Shanghai People's Republic of China
| | - Jianqiao Diao
- Department of ChemistryInstitutes of Biomedical Sciences and Multiscale Research Institute of Complex System, Fudan University Shanghai People's Republic of China
| | - Wenyu Wen
- Department of NeurosurgeryHuashan Hospital, Institutes of Biomedical Sciences, State Key Laboratory of Medical Neurobiology, Shanghai Medical College of Fudan University Shanghai People's Republic of China
- Department of Systems Biology for MedicineSchool of Basic Medical Sciences, Shanghai Medical College of Fudan University Shanghai People's Republic of China
| | - Wenning Wang
- Department of ChemistryInstitutes of Biomedical Sciences and Multiscale Research Institute of Complex System, Fudan University Shanghai People's Republic of China
| |
Collapse
|
22
|
Mirkovic M, Guilgur LG, Tavares A, Passagem-Santos D, Oliveira RA. Induced aneuploidy in neural stem cells triggers a delayed stress response and impairs adult life span in flies. PLoS Biol 2019; 17:e3000016. [PMID: 30794535 PMCID: PMC6402706 DOI: 10.1371/journal.pbio.3000016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 03/06/2019] [Accepted: 01/31/2019] [Indexed: 02/07/2023] Open
Abstract
Studying aneuploidy during organism development has strong limitations because chronic mitotic perturbations used to generate aneuploidy usually result in lethality. We developed a genetic tool to induce aneuploidy in an acute and time-controlled manner during Drosophila development. This is achieved by reversible depletion of cohesin, a key molecule controlling mitotic fidelity. Larvae challenged with aneuploidy hatch into adults with severe motor defects shortening their life span. Neural stem cells, despite being aneuploid, display a delayed stress response and continue proliferating, resulting in the rapid appearance of chromosomal instability, a complex array of karyotypes, and cellular abnormalities. Notably, when other brain-cell lineages are forced to self-renew, aneuploidy-associated stress response is significantly delayed. Protecting only the developing brain from induced aneuploidy is sufficient to rescue motor defects and adult life span, suggesting that neural tissue is the most ill-equipped to deal with developmental aneuploidy.
Collapse
|
23
|
A Novel Mutation in Brain Tumor Causes Both Neural Over-Proliferation and Neurodegeneration in Adult Drosophila. G3-GENES GENOMES GENETICS 2018; 8:3331-3346. [PMID: 30126833 PMCID: PMC6169379 DOI: 10.1534/g3.118.200627] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A screen for neuroprotective genes in Drosophila melanogaster led to the identification of a mutation that causes extreme, progressive loss of adult brain neuropil in conjunction with massive brain overgrowth. We mapped the mutation to the brain tumor (brat) locus, which encodes a tripartite motif-NCL-1, HT2A, and LIN-41 (TRIM-NHL) RNA-binding protein with established roles limiting stem cell proliferation in developing brain and ovary. However, a neuroprotective role for brat in the adult Drosophila brain has not been described previously. The new allele, bratcheesehead (bratchs), carries a mutation in the coiled-coil domain of the TRIM motif, and is temperature-sensitive. We demonstrate that mRNA and protein levels of neural stem cell genes are increased in heads of adult bratchs mutants and that the over-proliferation phenotype initiates prior to adult eclosion. We also report that disruption of an uncharacterized gene coding for a presumptive prolyl-4-hydroxylase strongly enhances the over-proliferation and neurodegeneration phenotypes. Together, our results reveal an unexpected role for brat that could be relevant to human cancer and neurodegenerative diseases.
Collapse
|
24
|
Olesnicky EC, Wright EG. Drosophila as a Model for Assessing the Function of RNA-Binding Proteins during Neurogenesis and Neurological Disease. J Dev Biol 2018; 6:E21. [PMID: 30126171 PMCID: PMC6162566 DOI: 10.3390/jdb6030021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/15/2018] [Accepted: 08/15/2018] [Indexed: 12/16/2022] Open
Abstract
An outstanding question in developmental neurobiology is how RNA processing events contribute to the regulation of neurogenesis. RNA processing events are increasingly recognized as playing fundamental roles in regulating multiple developmental events during neurogenesis, from the asymmetric divisions of neural stem cells, to the generation of complex and diverse neurite morphologies. Indeed, both asymmetric cell division and neurite morphogenesis are often achieved by mechanisms that generate asymmetric protein distributions, including post-transcriptional gene regulatory mechanisms such as the transport of translationally silent messenger RNAs (mRNAs) and local translation of mRNAs within neurites. Additionally, defects in RNA splicing have emerged as a common theme in many neurodegenerative disorders, highlighting the importance of RNA processing in maintaining neuronal circuitry. RNA-binding proteins (RBPs) play an integral role in splicing and post-transcriptional gene regulation, and mutations in RBPs have been linked with multiple neurological disorders including autism, dementia, amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), Fragile X syndrome (FXS), and X-linked intellectual disability disorder. Despite their widespread nature and roles in neurological disease, the molecular mechanisms and networks of regulated target RNAs have been defined for only a small number of specific RBPs. This review aims to highlight recent studies in Drosophila that have advanced our knowledge of how RBP dysfunction contributes to neurological disease.
Collapse
Affiliation(s)
- Eugenia C Olesnicky
- Department of Biology, University of Colorado Colorado Springs, 1420 Austin Bluffs Parkway, Colorado Springs, CO 80918, USA.
| | - Ethan G Wright
- Department of Biology, University of Colorado Colorado Springs, 1420 Austin Bluffs Parkway, Colorado Springs, CO 80918, USA.
| |
Collapse
|
25
|
Arbeille E, Bashaw GJ. Brain Tumor promotes axon growth across the midline through interactions with the microtubule stabilizing protein Apc2. PLoS Genet 2018; 14:e1007314. [PMID: 29617376 PMCID: PMC5902039 DOI: 10.1371/journal.pgen.1007314] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 04/16/2018] [Accepted: 03/19/2018] [Indexed: 11/20/2022] Open
Abstract
Commissural axons must cross the midline to establish reciprocal connections between the two sides of the body. This process is highly conserved between invertebrates and vertebrates and depends on guidance cues and their receptors to instruct axon trajectories. The DCC family receptor Frazzled (Fra) signals chemoattraction and promotes midline crossing in response to its ligand Netrin. However, in Netrin or fra mutants, the loss of crossing is incomplete, suggesting the existence of additional pathways. Here, we identify Brain Tumor (Brat), a tripartite motif protein, as a new regulator of midline crossing in the Drosophila CNS. Genetic analysis indicates that Brat acts independently of the Netrin/Fra pathway. In addition, we show that through its B-Box domains, Brat acts cell autonomously to regulate the expression and localization of Adenomatous polyposis coli-2 (Apc2), a key component of the Wnt canonical signaling pathway, to promote axon growth across the midline. Genetic evidence indicates that the role of Brat and Apc2 to promote axon growth across the midline is independent of Wnt and Beta-catenin-mediated transcriptional regulation. Instead, we propose that Brat promotes midline crossing through directing the localization or stability of Apc2 at the plus ends of microtubules in navigating commissural axons. These findings define a new mechanism in the coordination of axon growth and guidance at the midline. The establishment of neuronal connections that cross the midline of the animal is essential to generate neural circuits that coordinate the left and right sides of the body. Axons that cross the midline to form these connections are called commissural axons and the molecules and mechanisms that control midline axon crossing are remarkably conserved across animal evolution. In this study we have used a genetic screen in the fruit fly in an attempt to uncover additional players in this key developmental process, and have identified a novel role for the Brain Tumor (Brat) protein in promoting commissural axon growth across the midline. Unlike its previous described functions, in the context of midline axon guidance Brat cooperates with the microtubule stabilizing protein Apc2 to coordinate axon growth and guidance. Molecular and genetic analyses point to the conserved B box motifs of the Brat protein as key in promoting the association of Apc2 with the plus ends of microtubules. Brat is highly conserved and future studies will determine whether homologous genes play analogous roles in mammalian neural development.
Collapse
Affiliation(s)
- Elise Arbeille
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Greg J. Bashaw
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
- * E-mail:
| |
Collapse
|
26
|
Mora N, Oliva C, Fiers M, Ejsmont R, Soldano A, Zhang TT, Yan J, Claeys A, De Geest N, Hassan BA. A Temporal Transcriptional Switch Governs Stem Cell Division, Neuronal Numbers, and Maintenance of Differentiation. Dev Cell 2018; 45:53-66.e5. [DOI: 10.1016/j.devcel.2018.02.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 02/12/2018] [Accepted: 02/26/2018] [Indexed: 01/06/2023]
|
27
|
Landskron L, Steinmann V, Bonnay F, Burkard TR, Steinmann J, Reichardt I, Harzer H, Laurenson AS, Reichert H, Knoblich JA. The asymmetrically segregating lncRNA cherub is required for transforming stem cells into malignant cells. eLife 2018; 7:31347. [PMID: 29580384 PMCID: PMC5871330 DOI: 10.7554/elife.31347] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 02/06/2018] [Indexed: 12/20/2022] Open
Abstract
Tumor cells display features that are not found in healthy cells. How they become immortal and how their specific features can be exploited to combat tumorigenesis are key questions in tumor biology. Here we describe the long non-coding RNA cherub that is critically required for the development of brain tumors in Drosophila but is dispensable for normal development. In mitotic Drosophila neural stem cells, cherub localizes to the cell periphery and segregates into the differentiating daughter cell. During tumorigenesis, de-differentiation of cherub-high cells leads to the formation of tumorigenic stem cells that accumulate abnormally high cherub levels. We show that cherub establishes a molecular link between the RNA-binding proteins Staufen and Syncrip. As Syncrip is part of the molecular machinery specifying temporal identity in neural stem cells, we propose that tumor cells proliferate indefinitely, because cherub accumulation no longer allows them to complete their temporal neurogenesis program. Many biological signals control how cells grow and divide. However, cancer cells do not obey these growth-restricting signals, and as a result large tumors may develop. Recent experiments have suggested that stem cells – the precursors to the different types of specialized cells found in the body – are particularly important for generating tumors. A stem cell normally divides unequally to form a self-renewing cell and a more specialized cell (often a progenitor cell that will give rise to increasingly specialized cell types). The timing of when the specialization occurs can be key to guiding the ultimately produced cell progenies to their final identity. However, in a tumor cells can retain the ability to self-renew. Ultimately, the resulting ‘tumor stem cells’ become immortal and proliferate indefinitely. It is not fully understood why this uncontrolled proliferation occurs. Just like mammals (including humans), fruit flies can develop tumors. Some of the DNA mutations responsible for tumor development were already identified in flies as early as in the 1970s. This has made fruit flies a well-studied model system for uncovering the principle defects that cause tumors to form. Landskron et al. have now studied the neural stem cells found in brain tumors in fruit flies. Additional DNA mutations were not responsible for these cells becoming immortal. Instead, certain RNA molecules – products that are ‘transcribed’ from the DNA – were present in different amounts in tumor cells. The RNA that showed the greatest increase in tumor cells is a so-called long non-coding RNA named cherub. This RNA molecule has no important role in normal fruit flies, but is critical for tumor formation. Landskron et al. found that during cell division cherub segregates from the neural stem cells to the newly formed progenitor cells, where it breaks down over time. Progenitor cells that contain high levels of cherub give rise to tumor-generating neural stem cells. At the molecular level, cherubhelps two proteins to interact with each other: one called Syncrip that makes the neural stem cells take on a older identity, and another one (Staufen) that tethers it to the cell membrane. By restricting Syncrip to a particular location in the cell, cherub alters the timing of stem cell specialization, which contributes to tumor formation. Overall, the results presented by Landskron et al. reveal a new role for long non-coding RNAs: controlling the localization of the proteins that determine the fate of the cell. They also highlight a critical link between the timing of stem cell development and the proliferation of the cells. Further work is now needed to test whether the same control mechanism works in species other than fruit flies.
Collapse
Affiliation(s)
- Lisa Landskron
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Victoria Steinmann
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Francois Bonnay
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Thomas R Burkard
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Jonas Steinmann
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Ilka Reichardt
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Heike Harzer
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | | | | | - Jürgen A Knoblich
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| |
Collapse
|
28
|
Reichardt I, Bonnay F, Steinmann V, Loedige I, Burkard TR, Meister G, Knoblich JA. The tumor suppressor Brat controls neuronal stem cell lineages by inhibiting Deadpan and Zelda. EMBO Rep 2017; 19:102-117. [PMID: 29191977 DOI: 10.15252/embr.201744188] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 10/31/2017] [Accepted: 11/10/2017] [Indexed: 11/09/2022] Open
Abstract
The TRIM-NHL protein Brain tumor (Brat) acts as a tumor suppressor in the Drosophila brain, but how it suppresses tumor formation is not completely understood. Here, we combine temperature-controlled brat RNAi with transcriptome analysis to identify the immediate Brat targets in Drosophila neuroblasts. Besides the known target Deadpan (Dpn), our experiments identify the transcription factor Zelda (Zld) as a critical target of Brat. Our data show that Zld is expressed in neuroblasts and required to allow re-expression of Dpn in transit-amplifying intermediate neural progenitors. Upon neuroblast division, Brat is enriched in one daughter cell where its NHL domain directly binds to specific motifs in the 3'UTR of dpn and zld mRNA to mediate their degradation. In brat mutants, both Dpn and Zld continue to be expressed, but inhibition of either transcription factor prevents tumorigenesis. Our genetic and biochemical data indicate that Dpn inhibition requires higher Brat levels than Zld inhibition and suggest a model where stepwise post-transcriptional inhibition of distinct factors ensures sequential generation of fates in a stem cell lineage.
Collapse
Affiliation(s)
- Ilka Reichardt
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - François Bonnay
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Victoria Steinmann
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Inga Loedige
- Laboratory for RNA Biology, Biochemistry Center Regensburg (BZR), University of Regensburg, Regensburg, Germany
| | - Thomas R Burkard
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| | - Gunter Meister
- Laboratory for RNA Biology, Biochemistry Center Regensburg (BZR), University of Regensburg, Regensburg, Germany
| | - Juergen A Knoblich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna, Austria
| |
Collapse
|
29
|
Liu K, Shen D, Shen J, Gao SM, Li B, Wong C, Feng W, Song Y. The Super Elongation Complex Drives Neural Stem Cell Fate Commitment. Dev Cell 2017; 40:537-551.e6. [PMID: 28350987 DOI: 10.1016/j.devcel.2017.02.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 01/13/2017] [Accepted: 02/26/2017] [Indexed: 10/19/2022]
Abstract
Asymmetric stem cell division establishes an initial difference between a stem cell and its differentiating sibling, critical for maintaining homeostasis and preventing carcinogenesis. Yet the mechanisms that consolidate and lock in such initial fate bias remain obscure. Here, we use Drosophila neuroblasts to demonstrate that the super elongation complex (SEC) acts as an intrinsic amplifier to drive cell fate commitment. SEC is highly expressed in neuroblasts, where it promotes self-renewal by physically associating with Notch transcription activation complex and enhancing HES (hairy and E(spl)) transcription. HES in turn upregulates SEC activity, forming an unexpected self-reinforcing feedback loop with SEC. SEC inactivation leads to neuroblast loss, whereas its forced activation results in neural progenitor dedifferentiation and tumorigenesis. Our studies unveil an SEC-mediated intracellular amplifier mechanism in ensuring robustness and precision in stem cell fate commitment and provide mechanistic explanation for the highly frequent association of SEC overactivation with human cancers.
Collapse
Affiliation(s)
- Kun Liu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Dan Shen
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Jingwen Shen
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Shihong M Gao
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Bo Li
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Chouin Wong
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Weidong Feng
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China
| | - Yan Song
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
| |
Collapse
|
30
|
Arvola RM, Weidmann CA, Tanaka Hall TM, Goldstrohm AC. Combinatorial control of messenger RNAs by Pumilio, Nanos and Brain Tumor Proteins. RNA Biol 2017; 14:1445-1456. [PMID: 28318367 PMCID: PMC5785226 DOI: 10.1080/15476286.2017.1306168] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Eukaryotes possess a vast array of RNA-binding proteins (RBPs) that affect mRNAs in diverse ways to control protein expression. Combinatorial regulation of mRNAs by RBPs is emerging as the rule. No example illustrates this as vividly as the partnership of 3 Drosophila RBPs, Pumilio, Nanos and Brain Tumor, which have overlapping functions in development, stem cell maintenance and differentiation, fertility and neurologic processes. Here we synthesize 30 y of research with new insights into their molecular functions and mechanisms of action. First, we provide an overview of the key properties of each RBP. Next, we present a detailed analysis of their collaborative regulatory mechanism using a classic example of the developmental morphogen, hunchback, which is spatially and temporally regulated by the trio during embryogenesis. New biochemical, structural and functional analyses provide insights into RNA recognition, cooperativity, and regulatory mechanisms. We integrate these data into a model of combinatorial RNA binding and regulation of translation and mRNA decay. We then use this information, transcriptome wide analyses and bioinformatics predictions to assess the global impact of Pumilio, Nanos and Brain Tumor on gene regulation. Together, the results support pervasive, dynamic post-transcriptional control.
Collapse
Affiliation(s)
- René M Arvola
- a Department of Biological Chemistry , University of Michigan , Ann Arbor , Michigan , USA.,d Department of Biochemistry, Molecular Biology and Biophysics , University of Minnesota , Minneapolis , Minnesota , USA
| | - Chase A Weidmann
- b Department of Chemistry , University of North Carolina , Chapel Hill , USA
| | - Traci M Tanaka Hall
- c Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences , National Institutes of Health , Research Triangle Park, North Carolina , USA
| | - Aaron C Goldstrohm
- d Department of Biochemistry, Molecular Biology and Biophysics , University of Minnesota , Minneapolis , Minnesota , USA
| |
Collapse
|
31
|
Mukherjee S, Brat DJ. Molecular Programs Underlying Asymmetric Stem Cell Division and Their Disruption in Malignancy. Results Probl Cell Differ 2017; 61:401-421. [PMID: 28409315 DOI: 10.1007/978-3-319-53150-2_18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Asymmetric division of stem cells is a highly conserved and tightly regulated process by which a single stem cell produces two unequal daughter cells. One retains its stem cell identity while the other becomes specialized through a differentiation program and loses stem cell properties. Coordinating these events requires control over numerous intra- and extracellular biological processes and signaling networks. In the initial stages, critical events include the compartmentalization of fate determining proteins within the mother cell and their subsequent passage to the appropriate daughter cell in order to direct their destiny. Disturbance of these events results in an altered dynamic of self-renewing and differentiation within the cell population, which is highly relevant to the growth and progression of cancer. Other critical events include proper asymmetric spindle assembly, extrinsic regulation through micro-environmental cues, and non-canonical signaling networks that impact cell division and fate determination. In this review, we discuss mechanisms that maintain the delicate balance of asymmetric cell division in normal tissues and describe the current understanding how some of these mechanisms are deregulated in cancer.
Collapse
Affiliation(s)
- Subhas Mukherjee
- Departments of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Daniel J Brat
- Departments of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA.
- Winship Cancer Institute, Emory University, 1701 Uppergate Drive, Building C, Rm#C5038, Atlanta, GA, USA.
| |
Collapse
|
32
|
Sarkar A, Volff JN, Vaury C. piRNAs and their diverse roles: a transposable element-driven tactic for gene regulation? FASEB J 2016; 31:436-446. [PMID: 27799346 DOI: 10.1096/fj.201600637rr] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/14/2016] [Indexed: 01/12/2023]
Abstract
P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) are small, noncoding RNAs known for silencing transposable elements (TEs) in the germline of animals. Most genomes host TEs, which are notorious for mobilizing themselves and endangering survival of the host if not controlled. By silencing TEs in the germline, piRNAs prevent harmful mutations from being passed on to the next generation. How piRNAs are generated and how they silence TEs were the focus of researchers ever since their discovery. Now a spate of recent papers are beginning to tell us that piRNAs can play roles beyond TE silencing and are involved in diverse cellular processes from mRNA regulation to development or genome rearrangement. In this review, we discuss some of these recently reported roles. Data on these new roles are often rudimentary, and the involvement of piRNAs in these processes is yet to be definitely established. What is interesting is that the reports are on animals widely separated on the phylogenetic tree of life and that piRNAs were also found outside the gonadal tissues. Some of these piRNAs map to TE sequences, prompting us to hypothesize that genomes may have co-opted the TE-derived piRNA system for their own regulation.-Sarkar, A., Volff, J.-N., Vaury, C. piRNAs and their diverse roles: a transposable element-driven tactic for gene regulation?
Collapse
Affiliation(s)
- Arpita Sarkar
- Laboratoire de Génétique, Reproduction et Développement (GReD), Centre National de la Recherche Scientifique, INSERM, Université Clermont Auvergne, Clermont-Ferrand,France; and
| | - Jean-Nicolas Volff
- Institut de Génomique Fonctionnelle de Lyon, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Chantal Vaury
- Laboratoire de Génétique, Reproduction et Développement (GReD), Centre National de la Recherche Scientifique, INSERM, Université Clermont Auvergne, Clermont-Ferrand,France; and
| |
Collapse
|
33
|
Mukherjee S, Tucker-Burden C, Zhang C, Moberg K, Read R, Hadjipanayis C, Brat DJ. Drosophila Brat and Human Ortholog TRIM3 Maintain Stem Cell Equilibrium and Suppress Brain Tumorigenesis by Attenuating Notch Nuclear Transport. Cancer Res 2016; 76:2443-52. [PMID: 26893479 DOI: 10.1158/0008-5472.can-15-2299] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 02/01/2016] [Indexed: 11/16/2022]
Abstract
Cancer stem cells exert enormous influence on neoplastic behavior, in part by governing asymmetric cell division and the balance between self-renewal and multipotent differentiation. Growth is favored by deregulated stem cell division, which enhances the self-renewing population and diminishes the differentiation program. Mutation of a single gene in Drosophila, Brain Tumor (Brat), leads to disrupted asymmetric cell division resulting in dramatic neoplastic proliferation of neuroblasts and massive larval brain overgrowth. To uncover the mechanisms relevant to deregulated cell division in human glioma stem cells, we first developed a novel adult Drosophila brain tumor model using brat-RNAi driven by the neuroblast-specific promoter inscuteable Suppressing Brat in this population led to the accumulation of actively proliferating neuroblasts and a lethal brain tumor phenotype. brat-RNAi caused upregulation of Notch signaling, a node critical for self-renewal, by increasing protein expression and enhancing nuclear transport of Notch intracellular domain (NICD). In human glioblastoma, we demonstrated that the human ortholog of Drosophila Brat, tripartite motif-containing protein 3 (TRIM3), similarly suppressed NOTCH1 signaling and markedly attenuated the stem cell component. We also found that TRIM3 suppressed nuclear transport of active NOTCH1 (NICD) in glioblastoma and demonstrated that these effects are mediated by direct binding of TRIM3 to the Importin complex. Together, our results support a novel role for Brat/TRIM3 in maintaining stem cell equilibrium and suppressing tumor growth by regulating NICD nuclear transport. Cancer Res; 76(8); 2443-52. ©2016 AACR.
Collapse
Affiliation(s)
- Subhas Mukherjee
- Department of Pathology and Laboratory Medicine, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia
| | - Carol Tucker-Burden
- Department of Pathology and Laboratory Medicine, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia
| | - Changming Zhang
- Department of Pathology and Laboratory Medicine, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia
| | - Kenneth Moberg
- Department of Cell Biology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia
| | - Renee Read
- Department of Pharmacology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia
| | - Costas Hadjipanayis
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Daniel J Brat
- Department of Pathology and Laboratory Medicine, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia.
| |
Collapse
|
34
|
Abstract
TRIM-NHL proteins are key regulators of developmental transitions, for example promoting differentiation, while inhibiting cell growth and proliferation, in stem and progenitor cells. Abnormalities in these proteins have been also associated with human diseases, particularly affecting muscular and neuronal functions, making them potential targets for therapeutic intervention. The purpose of this review is to provide a systematic and comprehensive summary on the most studied TRIM-NHL proteins, highlighting examples where connections were established between structural features, molecular functions and biological outcomes.
Collapse
Affiliation(s)
- Cristina Tocchini
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Rafal Ciosk
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
| |
Collapse
|
35
|
Yi YH, Ma TH, Lee LW, Chiou PT, Chen PH, Lee CM, Chu YD, Yu H, Hsiung KC, Tsai YT, Lee CC, Chang YS, Chan SP, Tan BCM, Lo SJ. A Genetic Cascade of let-7-ncl-1-fib-1 Modulates Nucleolar Size and rRNA Pool in Caenorhabditis elegans. PLoS Genet 2015; 11:e1005580. [PMID: 26492166 PMCID: PMC4619655 DOI: 10.1371/journal.pgen.1005580] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 09/15/2015] [Indexed: 11/20/2022] Open
Abstract
Ribosome biogenesis takes place in the nucleolus, the size of which is often coordinated with cell growth and development. However, how metazoans control nucleolar size remains largely unknown. Caenorhabditis elegans provides a good model to address this question owing to distinct tissue distribution of nucleolar sizes and a mutant, ncl-1, which exhibits larger nucleoli than wild-type worms. Here, through a series of loss-of-function analyses, we report that the nucleolar size is regulated by a circuitry composed of microRNA let-7, translation repressor NCL-1, and a major nucleolar pre-rRNA processing protein FIB-1/fibrillarin. In cooperation with RNA binding proteins PUF and NOS, NCL-1 suppressed the translation of FIB-1/fibrillarin, while let-7 targeted the 3’UTR of ncl-1 and inhibited its expression. Consequently, the abundance of FIB-1 is tightly controlled and correlated with the nucleolar size. Together, our findings highlight a novel genetic cascade by which post-transcriptional regulators interplay in developmental control of nucleolar size and function. Among the RNA/protein bodies within the nucleus, nucleoli are essential factories for ribosome production and assembly. The size and morphology of the nucleolus is thus a cytological manifestation of protein biosynthesis and is closely coordinated with cell biology and even malignancy. However, without membrane delimitation, the principles that define nucleoli size are poorly understood. Caenorhabditis elegans represents an ideal model to address this question owing to distinct tissue distribution of nucleolar sizes and a mutant, ncl-1, which exhibits larger-than-normal nucleoli. We report here a genetic cascade of microRNA let-7 and translation repressor NCL-1, which tightly controls abundance of FIB-1/fibrillarin. This network ultimately contributes to developmental control of nucleolar size and function.
Collapse
Affiliation(s)
- Yung-Hsiang Yi
- Molecular Medicine Research Center, Chang Gung University, TaoYuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Tian-Hsiang Ma
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Li-Wei Lee
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Pey-Tsyr Chiou
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Po-Hsiang Chen
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Ching-Ming Lee
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Yu-De Chu
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsiang Yu
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Kuei-Ching Hsiung
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Yi-Tzang Tsai
- Molecular Medicine Research Center, Chang Gung University, TaoYuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Chi-Chang Lee
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Yu-Sun Chang
- Molecular Medicine Research Center, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
| | - Shih-Peng Chan
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei, Taiwan
- * E-mail: (SPC); (BCMT); (SJL)
| | - Bertrand Chin-Ming Tan
- Molecular Medicine Research Center, Chang Gung University, TaoYuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- * E-mail: (SPC); (BCMT); (SJL)
| | - Szecheng J. Lo
- Molecular Medicine Research Center, Chang Gung University, TaoYuan, Taiwan
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, TaoYuan, Taiwan
- * E-mail: (SPC); (BCMT); (SJL)
| |
Collapse
|
36
|
Abstract
The morphology and the connectivity of neuronal structures formed during early development must be actively maintained as the brain matures. Although impaired axon stability is associated with the progression of various neurological diseases, relatively little is known about the factors controlling this process. We identified Brain tumor (Brat), a conserved member of the TRIM-NHL family of proteins, as a new regulator of axon maintenance in Drosophila CNS. Brat function is dispensable for the initial growth of Mushroom Body axons, but is required for the stabilization of axon bundles. We found that Brat represses the translation of src64B, an upstream regulator of a conserved Rho-dependent pathway previously shown to promote axon retraction. Furthermore, brat phenotypes are phenocopied by src64B overexpression, and partially suppressed by reducing the levels of src64B or components of the Rho pathway, suggesting that brat promotes axon maintenance by downregulating the levels of Src64B. Finally, Brat regulates brain connectivity via its NHL domain, but independently of its previously described partners Nanos, Pumilio, and d4EHP. Thus, our results uncover a novel post-transcriptional regulatory mechanism that controls the maintenance of neuronal architecture by tuning the levels of a conserved rho-dependent signaling pathway.
Collapse
|
37
|
Laver JD, Li X, Ray D, Cook KB, Hahn NA, Nabeel-Shah S, Kekis M, Luo H, Marsolais AJ, Fung KY, Hughes TR, Westwood JT, Sidhu SS, Morris Q, Lipshitz HD, Smibert CA. Brain tumor is a sequence-specific RNA-binding protein that directs maternal mRNA clearance during the Drosophila maternal-to-zygotic transition. Genome Biol 2015; 16:94. [PMID: 25962635 PMCID: PMC4460960 DOI: 10.1186/s13059-015-0659-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 04/22/2015] [Indexed: 11/30/2022] Open
Abstract
Background Brain tumor (BRAT) is a Drosophila member of the TRIM-NHL protein family. This family is conserved among metazoans and its members function as post-transcriptional regulators. BRAT was thought to be recruited to mRNAs indirectly through interaction with the RNA-binding protein Pumilio (PUM). However, it has recently been demonstrated that BRAT directly binds to RNA. The precise sequence recognized by BRAT, the extent of BRAT-mediated regulation, and the exact roles of PUM and BRAT in post-transcriptional regulation are unknown. Results Genome-wide identification of transcripts associated with BRAT or with PUM in Drosophila embryos shows that they bind largely non-overlapping sets of mRNAs. BRAT binds mRNAs that encode proteins associated with a variety of functions, many of which are distinct from those implemented by PUM-associated transcripts. Computational analysis of in vitro and in vivo data identified a novel RNA motif recognized by BRAT that confers BRAT-mediated regulation in tissue culture cells. The regulatory status of BRAT-associated mRNAs suggests a prominent role for BRAT in post-transcriptional regulation, including a previously unidentified role in transcript degradation. Transcriptomic analysis of embryos lacking functional BRAT reveals an important role in mediating the decay of hundreds of maternal mRNAs during the maternal-to-zygotic transition. Conclusions Our results represent the first genome-wide analysis of the mRNAs associated with a TRIM-NHL protein and the first identification of an RNA motif bound by this protein family. BRAT is a prominent post-transcriptional regulator in the early embryo through mechanisms that are largely independent of PUM. Electronic supplementary material The online version of this article (doi:10.1186/s13059-015-0659-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- John D Laver
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Xiao Li
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - Debashish Ray
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - Kate B Cook
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - Noah A Hahn
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Syed Nabeel-Shah
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Mariana Kekis
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - Hua Luo
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Alexander J Marsolais
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Karen Yy Fung
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Timothy R Hughes
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - J Timothy Westwood
- Department of Biology, University of Toronto, Mississauga, 3359 Mississauga Road, Mississauga, Ontario, L5L 1C6, Canada.
| | - Sachdev S Sidhu
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada.
| | - Quaid Morris
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Donnelly Centre, University of Toronto, 160 College Street, Toronto, Ontario, M5S 3E1, Canada. .,Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario, M5S 3G4, Canada. .,Department of Computer Science, University of Toronto, 40 St. George Street, Toronto, Ontario, M5S 2E4, Canada.
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| | - Craig A Smibert
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada. .,Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
| |
Collapse
|
38
|
Mukherjee S, Kong J, Brat DJ. Cancer stem cell division: when the rules of asymmetry are broken. Stem Cells Dev 2014; 24:405-16. [PMID: 25382732 DOI: 10.1089/scd.2014.0442] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Asymmetric division of stem cells is a highly conserved and tightly regulated process by which a single stem cell produces two daughter cells and simultaneously directs the differential fate of both: one retains its stem cell identity while the other becomes specialized and loses stem cell properties. Coordinating these events requires control over numerous intra- and extracellular biological processes and signaling networks. In the initial stages, critical events include the compartmentalization of fate determining proteins within the mother cell and their subsequent passage to the appropriate daughter cell. Disturbance of these events results in an altered dynamic of self-renewing and differentiation within the cell population, which is highly relevant to the growth and progression of cancer. Other critical events include proper asymmetric spindle assembly, extrinsic regulation through micro-environmental cues, and noncanonical signaling networks that impact cell division and fate determination. In this review, we discuss mechanisms that maintain the delicate balance of asymmetric cell division in normal tissues and describe the current understanding how some of these mechanisms are deregulated in cancer. The universe is asymmetric and I am persuaded that life, as it is known to us, is a direct result of the asymmetry of the universe or of its indirect consequences. The universe is asymmetric. -Louis Pasteur.
Collapse
Affiliation(s)
- Subhas Mukherjee
- 1 Department of Pathology and Laboratory Medicine, Emory University , Atlanta, Georgia
| | | | | |
Collapse
|
39
|
Tocchini C, Keusch JJ, Miller SB, Finger S, Gut H, Stadler MB, Ciosk R. The TRIM-NHL protein LIN-41 controls the onset of developmental plasticity in Caenorhabditis elegans. PLoS Genet 2014; 10:e1004533. [PMID: 25167051 PMCID: PMC4148191 DOI: 10.1371/journal.pgen.1004533] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 06/11/2014] [Indexed: 12/30/2022] Open
Abstract
The mechanisms controlling cell fate determination and reprogramming are fundamental for development. A profound reprogramming, allowing the production of pluripotent cells in early embryos, takes place during the oocyte-to-embryo transition. To understand how the oocyte reprogramming potential is controlled, we sought Caenorhabditis elegans mutants in which embryonic transcription is initiated precociously in germ cells. This screen identified LIN-41, a TRIM-NHL protein and a component of the somatic heterochronic pathway, as a temporal regulator of pluripotency in the germline. We found that LIN-41 is expressed in the cytoplasm of developing oocytes, which, in lin-41 mutants, acquire pluripotent characteristics of embryonic cells and form teratomas. To understand LIN-41 function in the germline, we conducted structure-function studies. In contrast to other TRIM-NHL proteins, we found that LIN-41 is unlikely to function as an E3 ubiquitin ligase. Similar to other TRIM-NHL proteins, the somatic function of LIN-41 is thought to involve mRNA regulation. Surprisingly, we found that mutations predicted to disrupt the association of LIN-41 with mRNA, which otherwise compromise LIN-41 function in the heterochronic pathway in the soma, have only minor effects in the germline. Similarly, LIN-41-mediated repression of a key somatic mRNA target is dispensable for the germline function. Thus, LIN-41 appears to function in the germline and the soma via different molecular mechanisms. These studies provide the first insight into the mechanism inhibiting the onset of embryonic differentiation in developing oocytes, which is required to ensure a successful transition between generations. Reprogramming into a naïve, pluripotent state during the oocyte-to-embryo transition is directed by the oocyte cytoplasm. To understand how this reprogramming is controlled, we searched for C. elegans mutants in which the activation of embryonic genome, a landmark event demarcating the switch from a germline- to embryo-specific transcription, is initiated precociously in germ cells. This screen identified a novel function for LIN-41, a member of the TRIM-NHL protein family, in preventing a premature onset of embryonic-like differentiation and teratoma formation in developing oocytes, thus ensuring a successful passage between generations. This is the first example of such a regulator in cells that are poised for embryonic development. Interestingly, the majority of molecular “roadblocks” to reprograming that have been identified so far are epigenetic regulators. However, we propose that, at least in germ cells, LIN-41-like regulators may fulfill an analogous role in the cytoplasm, which has possible implications for the generation of human pluripotent stem cells.
Collapse
Affiliation(s)
- Cristina Tocchini
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jeremy J. Keusch
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Sarah B. Miller
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Susanne Finger
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Heinz Gut
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Michael B. Stadler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Rafal Ciosk
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- * E-mail:
| |
Collapse
|
40
|
Mei-P26 mediates tissue-specific responses to the Brat tumor suppressor and the dMyc proto-oncogene in Drosophila. Genetics 2014; 198:249-58. [PMID: 24990993 DOI: 10.1534/genetics.114.167502] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
TRIM-NHL proteins are a family of translational regulators that control cell growth, proliferation, and differentiation during development. Drosophila Brat and Mei-P26 TRIM-NHL proteins serve as tumor suppressors in stem cell lineages and have been proposed to exert this action, in part, via the repression of the protooncogene dMyc. Here we analyze the role of Brat, Mei-P26, and dMyc in regulating growth in Drosophila imaginal discs. As in stem cell lineages, Brat and Mei-P26 repress dMyc in epithelial cells by acting at the post-transcriptional and protein level, respectively. Analysis of cell and organ size unravel that Mei-P26 mediates tissue-specific responses to Brat and dMyc activities. Loss-of-function of brat and overexpression of dMyc induce overgrowth in stem cell lineages and eventually can participate in tumor formation. In contrast, an increase in Mei-P26 levels inhibits growth of epithelial cells in these two conditions. Upon depletion of Brat, Mei-P26 up-regulation prevents an increase in dMyc protein levels and leads to tissue undergrowth. This mechanism appears to be tissue-specific since Mei-P26 is not upregulated in brain tumors resulting from brat loss-of-function. Driving Mei-P26 expression in these tumors -mimicking the situation in epithelial cells- is sufficient to prevent dMyc accumulation, thus rescuing the overgrowth. Finally, we show that Mei-P26 upregulation mediates dMyc-induced apoptosis and limits dMyc growth potential in epithelial cells. These findings shed light on the tumor suppressor roles of TRIM-NHL proteins and underscore a new mechanism that maintains tissue homeostasis upon dMyc deregulation.
Collapse
|
41
|
Chen G, Kong J, Tucker-Burden C, Anand M, Rong Y, Rahman F, Moreno CS, Van Meir EG, Hadjipanayis CG, Brat DJ. Human Brat ortholog TRIM3 is a tumor suppressor that regulates asymmetric cell division in glioblastoma. Cancer Res 2014; 74:4536-48. [PMID: 24947043 DOI: 10.1158/0008-5472.can-13-3703] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cancer stem cells, capable of self-renewal and multipotent differentiation, influence tumor behavior through a complex balance of symmetric and asymmetric cell divisions. Mechanisms regulating the dynamics of stem cells and their progeny in human cancer are poorly understood. In Drosophila, mutation of brain tumor (brat) leads to loss of normal asymmetric cell division by developing neural cells and results in a massively enlarged brain composed of neuroblasts with neoplastic properties. Brat promotes asymmetric cell division and directs neural differentiation at least partially through its suppression on Myc. We identified TRIM3 (11p15.5) as a human ortholog of Drosophila brat and demonstrate its regulation of asymmetric cell division and stem cell properties of glioblastoma (GBM), a highly malignant human brain tumor. TRIM3 gene expression is markedly reduced in human GBM samples, neurosphere cultures, and cell lines and its reconstitution impairs growth properties in vitro and in vivo. TRIM3 expression attenuates stem-like qualities of primary GBM cultures, including neurosphere formation and the expression of stem cell markers CD133, Nestin, and Nanog. In GBM stem cells, TRIM3 expression leads to a greater percentage dividing asymmetrically rather than symmetrically. As with Brat in Drosophila, TRIM3 suppresses c-Myc expression and activity in human glioma cell lines. We also demonstrate a strong regulation of Musashi-Notch signaling by TRIM3 in GBM neurospheres and neural stem cells that may better explain its effect on stem cell dynamics. We conclude that TRIM3 acts as a tumor suppressor in GBM by restoring asymmetric cell division.
Collapse
Affiliation(s)
- Gang Chen
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Jun Kong
- Department of Biomedical Informatics, Emory University, Atlanta, Georgia
| | - Carol Tucker-Burden
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Monika Anand
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Yuan Rong
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Fahmia Rahman
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Carlos S Moreno
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia. Department of Biomedical Informatics, Emory University, Atlanta, Georgia. Winship Cancer Institute, Emory University, Atlanta, Georgia
| | - Erwin G Van Meir
- Department of Neurosurgery, Emory University, Atlanta, Georgia. Department of Hematology and Medical Oncology, Emory University, Atlanta, Georgia. Winship Cancer Institute, Emory University, Atlanta, Georgia
| | - Constantinos G Hadjipanayis
- Department of Neurosurgery, Emory University, Atlanta, Georgia. Winship Cancer Institute, Emory University, Atlanta, Georgia
| | - Daniel J Brat
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia. Department of Biomedical Informatics, Emory University, Atlanta, Georgia. Winship Cancer Institute, Emory University, Atlanta, Georgia.
| |
Collapse
|
42
|
Abstract
The Drosophila protein brain tumor (Brat) forms a complex with Pumilio (Pum) and Nanos (Nos) to repress hunchback (hb) mRNA translation at the posterior pole during early embryonic development. It is currently thought that complex formation is initiated by Pum, which directly binds the hb mRNA and subsequently recruits Nos and Brat. Here we report that, in addition to Pum, Brat also directly interacts with the hb mRNA. We identify Brat-binding sites distinct from the Pum consensus motif and show that RNA binding and translational repression by Brat do not require Pum, suggesting so far unrecognized Pum-independent Brat functions. Using various biochemical and biophysical methods, we also demonstrate that the NHL (NCL-1, HT2A, and LIN-41) domain of Brat, a domain previously believed to mediate protein-protein interactions, is a novel, sequence-specific ssRNA-binding domain. The Brat-NHL domain folds into a six-bladed β propeller, and we identify its positively charged top surface as the RNA-binding site. Brat belongs to the functional diverse TRIM (tripartite motif)-NHL protein family. Using structural homology modeling, we predict that the NHL domains of all TRIM-NHL proteins have the potential to bind RNA, indicating that Brat is part of a conserved family of RNA-binding proteins.
Collapse
|
43
|
Eroglu E, Burkard TR, Jiang Y, Saini N, Homem CCF, Reichert H, Knoblich JA. SWI/SNF complex prevents lineage reversion and induces temporal patterning in neural stem cells. Cell 2014; 156:1259-1273. [PMID: 24630726 DOI: 10.1016/j.cell.2014.01.053] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 11/11/2013] [Accepted: 01/16/2014] [Indexed: 12/22/2022]
Abstract
Members of the SWI/SNF chromatin-remodeling complex are among the most frequently mutated genes in human cancer, but how they suppress tumorigenesis is currently unclear. Here, we use Drosophila neuroblasts to demonstrate that the SWI/SNF component Osa (ARID1) prevents tumorigenesis by ensuring correct lineage progression in stem cell lineages. We show that Osa induces a transcriptional program in the transit-amplifying population that initiates temporal patterning, limits self-renewal, and prevents dedifferentiation. We identify the Prdm protein Hamlet as a key component of this program. Hamlet is directly induced by Osa and regulates the progression of progenitors through distinct transcriptional states to limit the number of transit-amplifying divisions. Our data provide a mechanistic explanation for the widespread tumor suppressor activity of SWI/SNF. Because the Hamlet homologs Evi1 and Prdm16 are frequently mutated in cancer, this mechanism could well be conserved in human stem cell lineages. PAPERCLIP:
Collapse
Affiliation(s)
- Elif Eroglu
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Thomas R Burkard
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Yanrui Jiang
- Biozentrum, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Nidhi Saini
- Biozentrum, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Catarina C F Homem
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Heinrich Reichert
- Biozentrum, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Juergen A Knoblich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr-Gasse 3, 1030 Vienna, Austria.
| |
Collapse
|
44
|
Jüschke C, Dohnal I, Pichler P, Harzer H, Swart R, Ammerer G, Mechtler K, Knoblich JA. Transcriptome and proteome quantification of a tumor model provides novel insights into post-transcriptional gene regulation. Genome Biol 2013; 14:r133. [PMID: 24289286 PMCID: PMC4053992 DOI: 10.1186/gb-2013-14-11-r133] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 11/30/2013] [Indexed: 11/25/2022] Open
Abstract
Background Genome‐wide transcriptome analyses have given systems‐level insights into gene regulatory networks. Due to the limited depth of quantitative proteomics, however, our understanding of post‐transcriptional gene regulation and its effects on protein‐complex stoichiometry are lagging behind. Results Here, we employ deep sequencing and the isobaric tag for relative and absolute quantification (iTRAQ) technology to determine transcript and protein expression changes of a Drosophila brain tumor model at near genome‐wide resolution. In total, we quantify more than 6,200 tissue‐specific proteins, corresponding to about 70% of all transcribed protein‐coding genes. Using our integrated data set, we demonstrate that post‐transcriptional gene regulation varies considerably with biological function and is surprisingly high for genes regulating transcription. We combine our quantitative data with protein‐protein interaction data and show that post‐transcriptional mechanisms significantly enhance co‐regulation of protein‐complex subunits beyond transcriptional co‐regulation. Interestingly, our results suggest that only about 11% of the annotated Drosophila protein complexes are co‐regulated in the brain. Finally, we refine the composition of some of these core protein complexes by analyzing the co‐regulation of potential subunits. Conclusions Our comprehensive transcriptome and proteome data provide a valuable resource for quantitative biology and offer novel insights into understanding post‐transcriptional gene regulation in a tumor model.
Collapse
|
45
|
Komori H, Xiao Q, McCartney BM, Lee CY. Brain tumor specifies intermediate progenitor cell identity by attenuating β-catenin/Armadillo activity. Development 2013; 141:51-62. [PMID: 24257623 DOI: 10.1242/dev.099382] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
During asymmetric stem cell division, both the daughter stem cell and the presumptive intermediate progenitor cell inherit cytoplasm from their parental stem cell. Thus, proper specification of intermediate progenitor cell identity requires an efficient mechanism to rapidly extinguish the activity of self-renewal factors, but the mechanisms remain unknown in most stem cell lineages. During asymmetric division of a type II neural stem cell (neuroblast) in the Drosophila larval brain, the Brain tumor (Brat) protein segregates unequally into the immature intermediate neural progenitor (INP), where it specifies INP identity by attenuating the function of the self-renewal factor Klumpfuss (Klu), but the mechanisms are not understood. Here, we report that Brat specifies INP identity through its N-terminal B-boxes via a novel mechanism that is independent of asymmetric protein segregation. Brat-mediated specification of INP identity is critically dependent on the function of the Wnt destruction complex, which attenuates the activity of β-catenin/Armadillo (Arm) in immature INPs. Aberrantly increasing Arm activity in immature INPs further exacerbates the defects in the specification of INP identity and enhances the supernumerary neuroblast mutant phenotype in brat mutant brains. By contrast, reducing Arm activity in immature INPs suppresses supernumerary neuroblast formation in brat mutant brains. Finally, reducing Arm activity also strongly suppresses supernumerary neuroblasts induced by overexpression of klu. Thus, the Brat-dependent mechanism extinguishes the function of the self-renewal factor Klu in the presumptive intermediate progenitor cell by attenuating Arm activity, balancing stem cell maintenance and progenitor cell specification.
Collapse
Affiliation(s)
- Hideyuki Komori
- Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | | | | | | |
Collapse
|
46
|
Brain tumor regulates neuromuscular synapse growth and endocytosis in Drosophila by suppressing mad expression. J Neurosci 2013; 33:12352-63. [PMID: 23884941 DOI: 10.1523/jneurosci.0386-13.2013] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The precise regulation of synaptic growth is critical for the proper formation and plasticity of functional neural circuits. Identification and characterization of factors that regulate synaptic growth and function have been under intensive investigation. Here we report that brain tumor (brat), which was identified as a translational repressor in multiple biological processes, plays a crucial role at Drosophila neuromuscular junction (NMJ) synapses. Immunohistochemical analysis demonstrated that brat mutants exhibited synaptic overgrowth characterized by excess satellite boutons at NMJ terminals, whereas electron microscopy revealed increased synaptic vesicle size but reduced density at active zones compared with wild-types. Spontaneous miniature excitatory junctional potential amplitudes were larger and evoked quantal content was lower at brat mutant NMJs. In agreement with the morphological and physiological phenotypes, loss of Brat resulted in reduced FM1-43 uptake at the NMJ terminals, indicating that brat regulates synaptic endocytosis. Genetic analysis revealed that the actions of Brat at synapses are mediated through mothers against decapentaplegic (Mad), the signal transduction effector of the bone morphogenetic protein (BMP) signaling pathway. Furthermore, biochemical analyses showed upregulated levels of Mad protein but normal mRNA levels in the larval brains of brat mutants, suggesting that Brat suppresses Mad translation. Consistently, knockdown of brat by RNA interference in Drosophila S2 cells also increased Mad protein level. These results together reveal an important and previously unidentified role for Brat in synaptic development and endocytosis mediated by suppression of BMP signaling.
Collapse
|
47
|
Insco ML, Bailey AS, Kim J, Olivares GH, Wapinski OL, Tam CH, Fuller MT. A self-limiting switch based on translational control regulates the transition from proliferation to differentiation in an adult stem cell lineage. Cell Stem Cell 2013; 11:689-700. [PMID: 23122292 DOI: 10.1016/j.stem.2012.08.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 07/13/2012] [Accepted: 08/28/2012] [Indexed: 12/11/2022]
Abstract
In adult stem cell lineages, progenitor cells commonly undergo mitotic transit amplifying (TA) divisions before terminal differentiation, allowing production of many differentiated progeny per stem cell division. Mechanisms that limit TA divisions and trigger the switch to differentiation may protect against cancer by preventing accumulation of oncogenic mutations in the proliferating population. Here we show that the switch from TA proliferation to differentiation in the Drosophila male germline stem cell lineage is mediated by translational control. The TRIM-NHL tumor suppressor homolog Mei-P26 facilitates accumulation of the differentiation regulator Bam in TA cells. In turn, Bam and its partner Bgcn bind the mei-P26 3' untranslated region and repress translation of mei-P26 in late TA cells. Thus, germ cells progress through distinct, sequential regulatory states, from Mei-P26 on/Bam off to Bam on/Mei-P26 off. TRIM-NHL homologs across species facilitate the switch from proliferation to differentiation, suggesting a conserved developmentally programmed tumor suppressor mechanism.
Collapse
Affiliation(s)
- Megan L Insco
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA
| | | | | | | | | | | | | |
Collapse
|
48
|
Homem CCF, Knoblich JA. Drosophila neuroblasts: a model for stem cell biology. Development 2013; 139:4297-310. [PMID: 23132240 DOI: 10.1242/dev.080515] [Citation(s) in RCA: 300] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Drosophila neuroblasts, the stem cells of the developing fly brain, have emerged as a key model system for neural stem cell biology and have provided key insights into the mechanisms underlying asymmetric cell division and tumor formation. More recently, they have also been used to understand how neural progenitors can generate different neuronal subtypes over time, how their cell cycle entry and exit are coordinated with development, and how proliferation in the brain is spared from the growth restrictions that occur in other organs upon starvation. In this Primer, we describe the biology of Drosophila neuroblasts and highlight the most recent advances made using neuroblasts as a model system.
Collapse
Affiliation(s)
- Catarina C F Homem
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Dr Bohr Gasse 3-5, 1030 Vienna, Austria
| | | |
Collapse
|
49
|
Liu Y, Raheja R, Yeh N, Ciznadija D, Pedraza AM, Ozawa T, Hukkelhoven E, Erdjument-Bromage H, Tempst P, Gauthier NP, Brennan C, Holland EC, Koff A. TRIM3, a tumor suppressor linked to regulation of p21(Waf1/Cip1.). Oncogene 2013; 33:308-15. [PMID: 23318451 PMCID: PMC3928554 DOI: 10.1038/onc.2012.596] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 11/01/2012] [Accepted: 11/04/2012] [Indexed: 02/06/2023]
Abstract
The TRIM family of genes is largely studied because of their roles in development, differentiation and host cell antiviral defenses; however, roles in cancer biology are emerging. Loss of heterozygosity of the TRIM3 locus in ∼20% of human glioblastomas raised the possibility that this NHL-domain containing member of the TRIM gene family might be a mammalian tumor suppressor. Consistent with this, reducing TRIM3 expression increased the incidence of and accelerated the development of platelet-derived growth factor -induced glioma in mice. Furthermore, TRIM3 can bind to the cdk inhibitor p21(WAF1/CIP1). Thus, we conclude that TRIM3 is a tumor suppressor mapping to chromosome 11p15.5 and that it might block tumor growth by sequestering p21 and preventing it from facilitating the accumulation of cyclin D1-cdk4.
Collapse
Affiliation(s)
- Y Liu
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - R Raheja
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - N Yeh
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - D Ciznadija
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - A M Pedraza
- Human Oncology and Pathogenesis, New York, NY, USA
| | - T Ozawa
- Cancer Biology, New York, NY, USA
| | - E Hukkelhoven
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - H Erdjument-Bromage
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - P Tempst
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - N P Gauthier
- Computational Biology. Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - C Brennan
- Human Oncology and Pathogenesis, New York, NY, USA
| | | | - A Koff
- Programs in Molecular Biology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
50
|
Hirth F. Stem Cells and Asymmetric Cell Division. Regen Med 2013. [DOI: 10.1007/978-94-007-5690-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|