Article
Neurosciences
Phu Duong, Raghu Ramesh, Andrew Schneider, Seongsik Won, Aaron J. J. Cooper, John Svaren
Summary: Schwann cell programming during myelination involves activation of gene expression and repression of neural crest/embryonic differentiation genes. The loss of EED subunit of PRC2 leads to inappropriate gene activation and premature activation of the nerve injury program. The H2AK119 deubiquitinase Bap1 is required for myelin homeostasis and restriction of polycomb-associated histone modifications in Schwann cells.
Review
Multidisciplinary Sciences
Ipek Selcen, Emily Prentice, Patrizia Casaccia
Summary: This passage focuses on the epigenetic landscape of oligodendrocyte lineage cells, which refers to the cell-specific modifications of DNA, chromatin, and RNA that define a unique gene expression pattern of functionally specialized cells. It discusses the epigenetic changes occurring as progenitors differentiate into myelin-forming cells and respond to the local environment, including modifications of DNA, RNA, nucleosomal histones, chromatin organization, and local remodeling. The passage also explores the relationship between epigenetic modulators and RNA processing, as well as the reciprocal relationship between the epigenome and cell nucleus mechanical properties.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2023)
Review
Plant Sciences
Lea Faivre, Daniel Schubert
Summary: Chromatin is important for transcriptional regulation, and the histone modifications H3K4me3 and H3K27me3 are usually described as mutually exclusive activator and repressor. However, recent studies show that these marks can co-exist, forming a distinctive chromatin state called bivalency. The role of bivalency in transcriptional regulation remains unclear, but it is proposed to maintain transcriptional plasticity and prevent irreversible silencing of target genes. This review explores the potential factors involved in bivalency and highlights techniques for further study.
JOURNAL OF EXPERIMENTAL BOTANY
(2023)
Article
Neurosciences
Haley Jeanette, Leandro N. Marziali, Urja Bhatia, Abigail Hellman, Jacob Herron, Ashley M. Kopec, Maria Laura Feltri, Yannick Poitelon, Sophie Belin
Summary: YAP and TAZ, effectors of the Hippo pathway, play a regulatory role in the proliferation and differentiation of repair Schwann cells during peripheral nerve regeneration, contributing to remyelination over time.
Article
Cell Biology
Nadezda A. Fursova, Anne H. Turberfield, Neil P. Blackledge, Emma L. Findlater, Anna Lastuvkova, Miles K. Huseyin, Paula Dobrinic, Robert J. Klose
Summary: Histone modifications play crucial roles in gene regulation and development, with little known about modifications found broadly throughout the genome. BAP1 deubiquitylase constrains H2AK119ub1 accumulation throughout the genome, impacting gene expression and transcription. Failure to constrain H2AK119ub1 compromises Polycomb complex occupancy at certain target genes, resulting in their derepression.
GENES & DEVELOPMENT
(2021)
Article
Genetics & Heredity
Jeanne-Marie E. McPherson, Lucy C. Grossmann, Harmony R. Salzler, Robin L. Armstrong, Esther Kwon, A. Gregory Matera, Daniel J. McKay, Robert J. Duronio
Summary: The chromatin of animal cells contains two types of histones: canonical histones that are expressed during S phase of the cell cycle to package the newly replicated genome, and variant histones with specialized functions that are expressed throughout the cell cycle and in non-proliferating cells. Determining whether and how canonical and variant histones cooperate to regulate genome function is integral to understanding how chromatin-based processes affect normal and pathological development.
Article
Multidisciplinary Sciences
Hye-Jin Park, Eric Tsai, Dennis Huang, Michael Weaver, Luciana Frick, Ace Alcantara, John J. Moran, Julia Patzig, Carmen V. Melendez-Vasquez, Gerald R. Crabtree, M. L. Feltri, John Svaren, Patrizia Casaccia
Summary: In response to external signals, cells use the protein ACTL6A to integrate axonal caliber recognition with the process of myelination in peripheral nerves, ensuring proper nerve function.
Article
Genetics & Heredity
Daniel N. Weinberg, Phillip Rosenbaum, Xiao Chen, Douglas Barrows, Cynthia Horth, Matthew R. Marunde, Irina K. Popova, Zachary B. Gillespie, Michael-Christopher Keogh, Chao Lu, Jacek Majewski, C. David Allis
Summary: The study found that mutations in the DNMT3A PWWP domain identified in paragangliomas and microcephalic dwarfism promote aberrant localization of DNMT3A to CGIs in a PRC1-dependent manner. DNMT3A PWWP mutants accumulate at regions containing PRC1-mediated formation of monoubiquitylated histone H2A lysine 119 (H2AK119ub), irrespective of the amounts of PRC2-catalyzed formation of trimethylated histone H3 lysine 27 (H3K27me3). DNMT3A interacts with H2AK119ub-modified nucleosomes through a putative amino-terminal ubiquitin-dependent recruitment region, providing an alternative form of DNMT3A genomic targeting that is augmented by the loss of PWWP reader function.
Review
Plant Sciences
Dong-Hwan Kim
Summary: Polycomb repressive complexes (PRCs) are crucial for the growth and development of eukaryotes, with conserved components among most eukaryotes. The study of PRCs' gene silencing in plants has contributed to the understanding of the epigenetic control of developmental programs. This review provides current knowledge on PcG-mediated gene regulation, focusing on its role in various aspects of plant development and the molecular mechanisms involved, specifically in Arabidopsis plants.
JOURNAL OF PLANT BIOLOGY
(2023)
Review
Biochemistry & Molecular Biology
Fernando Baile, Angeles Gomez-Zambrano, Myriam Calonje
Summary: This review discusses the function, composition, and mechanisms of plant PcG complexes, as well as their potential role in shaping chromatin 3D architecture.
PLANT COMMUNICATIONS
(2022)
Article
Biochemistry & Molecular Biology
Jose A. Gomez-Sanchez, Nikiben Patel, Fernanda Martirena, Shaline Fazal, Clara Mutschler, Hugo Cabedo
Summary: The peripheral nervous system (PNS) has superior regenerative capacity compared to the central nervous system (CNS). This regenerative ability is attributed to the reprogramming of Schwann cells (SC) into repair Schwann cells, which support axonal growth, myelin degradation, neurotrophic factor secretion, and axonal growth guidance. Epigenetic regulations, particularly histone acetylation and deacetylation, play a crucial role in SC reprogramming and nerve regeneration. This review focuses on Zn2+-dependent histone deacetylases (HDACs) and their importance in repair SC biology and remyelination after PNS injury.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Multidisciplinary Sciences
Filippo Ciabrelli, Leily Rabbani, Francesco Cardamone, Fides Zenk, Eva Loeser, Melanie A. Schaechtle, Marina Mazina, Vincent Loubiere, Nicola Iovino
Summary: We conducted an in vivo RNA interference reverse genetic screen in Drosophila melanogaster and identified histone acetyltransferases (HATs) and histone deacetylases as key regulators of zygotic genome activation (ZGA). We showed that Nejire and Gcn5 are responsible for acetylation of different lysine sites on histone H3 during ZGA, with these marks being enriched at actively transcribed genes. Surprisingly, catalytic dead mutants of Nejire or Gcn5 can still activate ZGA and transactivate a reporter gene in vitro. Overall, our study identifies Nejire and Gcn5 as crucial regulators of ZGA.
Article
Multidisciplinary Sciences
Jia-Ray Yu, Gary LeRoy, Devin Bready, Joshua D. Frenster, Ricardo Saldana-Meyer, Ying Jin, Nicolas Descostes, James M. Stafford, Dimitris G. Placantonakis, Danny Reinberg
Summary: The study identified that H3K36me2 promotes tumorigenesis in H3K27M-DIPG by affecting the writing activity of NSD1 and NSD2, as well as the reading factors LEDGF and HDGF2. Loss of NSD1/2 impedes cellular proliferation and tumorigenesis.
Article
Neurosciences
Akihiro Ishii, Miki Furusho, Rashmi Bansal
Summary: Multiple intracellular signaling pathways, including Mek/ERK1/2-MAPK and PI3K/Akt/mTOR, are involved in regulating myelination in the peripheral nervous system. The roles of these pathways may differ during development and adulthood, highlighting the complexity of their interactions in Schwann cells.
Article
Chemistry, Medicinal
Haili Xiao, Chao Wei, Huiying Liu, Zhiqiang Li, Cihua Zheng, Jun Luo
Summary: The natural drug lentinan has been found to regulate autophagy, promoting the clearance of myelin debris and enhancing nerve regeneration. The study demonstrated that lentinan activates the AMPK/mTOR signaling pathway, accelerating autophagic flux and promoting the phagocytosis of myelin debris by Schwann cells. These findings suggest that lentinan may be a cost-effective and natural treatment for peripheral nerve injury.
PHYTOTHERAPY RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Phu Duong, Ki H. Ma, Raghu Ramesh, John J. Moran, Seongsik Won, John Svaren
Summary: The study indicates that H3K27 demethylation is not necessary for the induction of injury response genes in Schwann cells, suggesting other mechanisms may be involved in activating Polycomb-repressed injury genes.
JOURNAL OF BIOLOGICAL CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Hye-Jin Park, Eric Tsai, Dennis Huang, Michael Weaver, Luciana Frick, Ace Alcantara, John J. Moran, Julia Patzig, Carmen V. Melendez-Vasquez, Gerald R. Crabtree, M. L. Feltri, John Svaren, Patrizia Casaccia
Summary: In response to external signals, cells use the protein ACTL6A to integrate axonal caliber recognition with the process of myelination in peripheral nerves, ensuring proper nerve function.
Article
Biochemistry & Molecular Biology
Francesca A. Veneri, Valeria Prada, Rosa Mastrangelo, Cinzia Ferri, Lucilla Nobbio, Mario Passalacqua, Maria Milanesi, Francesca Bianchi, Ubaldo Del Carro, Jean-Michel Vallat, Phu Duong, John Svaren, Angelo Schenone, Marina Grandis, Maurizio D'Antonio
Summary: This study investigates the impact of misglycosylation on the functionality of P0, the major structural glycoprotein of peripheral nerve myelin. Through the use of CRISPR/Cas9, a mouse model carrying the MPZ(D61N) mutation was generated to mimic the severe early-onset form of CMT1B seen in humans. The findings suggest that hyperglycosylation interferes with myelin formation and leads to motor impairment and other pathological changes.
HUMAN MOLECULAR GENETICS
(2022)
Article
Immunology
Amanda Contreras, Darin L. Wiesner, Brock Kingstad-Bakke, Woojong Lee, John P. Svaren, Bruce S. Klein, M. Suresh
Summary: This study investigated the role of Bach2 in regulating Treg homeostasis and effector functions in peripheral Tregs. The results suggest that Bach2 plays vital roles in limiting the premature differentiation of Tregs into effector Tregs in lymphoid tissues and restraining Type 2 inflammation in the lungs. The findings of this study highlight the importance of dysregulated Tregs in the pathogenesis of airway hypersensitivities, asthma, and other allergic disorders.
JOURNAL OF IMMUNOLOGY RESEARCH
(2022)
Article
Clinical Neurology
Menelaos Pipis, Seongsik Won, Roy Poh, Stephanie Efthymiou, James M. Polke, Mariola Skorupinska, Julian Blake, Alexander M. Rossor, John J. Moran, Pinki Munot, Francesco Muntoni, Matilde Laura, John Svaren, Mary M. Reilly
Summary: CMT1A is the most common form of inherited neuropathy, characterized by early onset progressive weakness and sensory loss, caused by duplication of the PMP22 gene. The study indirectly demonstrates that microRNA miR-29a represses the expression of PMP22, and loss of this effect can lead to more severe disease.
Article
Neurosciences
Phu Duong, Raghu Ramesh, Andrew Schneider, Seongsik Won, Aaron J. J. Cooper, John Svaren
Summary: Schwann cell programming during myelination involves activation of gene expression and repression of neural crest/embryonic differentiation genes. The loss of EED subunit of PRC2 leads to inappropriate gene activation and premature activation of the nerve injury program. The H2AK119 deubiquitinase Bap1 is required for myelin homeostasis and restriction of polycomb-associated histone modifications in Schwann cells.
Meeting Abstract
Clinical Neurology
Silvia Cipriani, Emanuela Porrello, Roberta Di Guardo, Matteo Cerea, Amanda Heslegrave, Phu Duong, John Svaren, Stefano Previtali, Alessandra Bolino
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Mehdi Momen, Emily Binversie, Lauren Baker, Jordan Gruel, Margaret Patterson, Alexander Chu, Ryan Anderson, Nyah Kohler, Kearney Hannah, John Svaren, Peter Muir, Susannah Sample
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Mehdi Momen, Emily Binversie, Lauren Baker, Jordan Gruel, Margaret Patterson, Alexander Chu, Ryan Anderson, Nyah Kohler, Kearney Hannah, John Svaren, Peter Muir, Susannah Sample
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Emma Nicolaisen, Mary Reilly, John Svaren, Steven Scherer, Davide Pareyson, David Herrmann, Michael Shy
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Emma Nicolaisen, Xingyao Wu, Valeria Prada, Sydney Stork, Nidia Villalpando, Riccardo Zuccarino, Yunhong Bai, John Moran, Seongsik Won, Phu Duong, Alexander Rossor, Mary Reilly, Maurizio D'Antonio, Michael Shy, John Svaren
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Raghu Ramesh, Yanti Manurung, Todd Blakely, Ki Ma, Seongsik Won, Eugene Wyatt, Rajeshwar Awatramani, John Svaren
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Thierry Touvier, Francesca Veneri, Anke Claessens, Cinzia Ferri, Rosa Mastrangelo, Ubaldo Del Carro, Christina Barkauskas, Laurie Glimcher, Randal J. Kaufman, Phu Duong, John Svaren, Michael Shy, Lawrence Wrabetz, Maurizio D'Antonio
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2022)
Meeting Abstract
Clinical Neurology
Jacquelyn Perino, Margaret Patterson, Mehdi Momen, Mina Borisova, Amanda Heslegrave, Henrik Zetterberg, Jordan Gruel, Emily Binversie, Lauren Baker, John Svaren, Susannah Sample
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2021)
Meeting Abstract
Clinical Neurology
Thierry Touvier, Francesca Veneri, Anke Claessens, Rosa Mastrangelo, Cinzia Ferri, Francesca Bianchi, Ubaldo Del Carro, Laurie Glimcher, Christina Barkauskas, Lawrence Wrabetz, Phu Duong, John Svaren, Michael Shy, Maurizio D'Antonio
JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM
(2021)