The Role of Pioneer Factors Zelda and Grainyhead at the Maternal-to-Zygotic Transition (Melissa Harrison)

In this episode of the Epigenetics Podcast, we caught up with Emily Bernstein from Icahn Schoon of Medicine at Mount Sinai to talk about her work on MacroH2A function and the role of Polycomb proteins in its epigenetic regulation, and how this affects in stem cell development and disease. The Bernstein Lab focuses on histone variants, in particular the H2A variant macroH2A. Chromatin architecture is influenced by the composition of the nucleosome and, hence, exchanging the core histones for histone variants can have a major impact on chromatin structure. MacroH2A variantsare the most unique histone variants due to a 30kDa non-histone domain (macro domain) at their C-termini. This macro domain likely confers important functions to macroH2A variants, which have important regulatory roles in the cell. Among other things, the Bernstein Lab has shown that macroH2A is enriched at a critical set of Utx target genes whose expression is critical for the early stages of induced pluripotency, and that macroH2A plays a role as a barrier to tumorigenesis.   References Kapoor, A., Goldberg, M. S., Cumberland, L. K., Ratnakumar, K., Segura, M. F., Emanuel, P. O., Menendez, S., Vardabasso, C., LeRoy, G., Vidal, C. I., Polsky, D., Osman, I., Garcia, B. A., Hernando, E., & Bernstein, E. (2010). The histone variant macroH2A suppresses melanoma progression through regulation of CDK8. Nature, 468(7327), 1105–1109. https://doi.org/10.1038/nature09590 Vardabasso, C., Gaspar-Maia, A., Hasson, D., Pünzeler, S., Valle-Garcia, D., Straub, T., Keilhauer, E. C., Strub, T., Dong, J., Panda, T., Chung, C.-Y., Yao, J. L., Singh, R., Segura, M. F., Fontanals-Cirera, B., Verma, A., Mann, M., Hernando, E., Hake, S. B., & Bernstein, E. (2015). Histone Variant H2A.Z.2 Mediates Proliferation and Drug Sensitivity of Malignant Melanoma. Molecular Cell, 59(1), 75–88. https://doi.org/10.1016/j.molcel.2015.05.009 Sun, Zhen, Dan Filipescu, Joshua Andrade, Alexandre Gaspar-Maia, Beatrix Ueberheide, and Emily Bernstein. 2018. “Transcription-Associated Histone Pruning Demarcates MacroH2A Chromatin Domains.” Nature Structural & Molecular Biology 25(10):958–70. doi: 10.1038/s41594-018-0134-5.   Related Episodes Influence of Histone Variants on Chromatin Structure and Metabolism (Marcus Buschbeck) Regulation of Chromatin Organization by Histone Chaperones (Geneviève Almouzni) Variants of Core Histones: Modulators of Chromatin Structure and Function (Sandra Hake)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

2 Joulu 202132min

In this episode of the Epigenetics Podcast, we caught up with Jane Skok from New York University School of Medicine to talk about her work on spatio-temporal alterations in chromosome dynamics. Studies demonstrating that nuclear organization and long-range chromatin interactions play essential roles in gene regulation have been the focus of the Skok Lab, where the team has played a leading role. Their initial studies focused on lymphocyte development and the control of V(D)J recombination, a key part of generating the diverse repertoire of B-cell antibodies and T-cell receptors. The Skok Lab was among the first to demonstrate the possibility of chromatin forming dynamic loops which lead to the formation of reversible intra-locus loops in the immunoglobulin and T-cell receptor loci and to a profound impact on the ability of B and T cells to generate receptor diversity.   References Roldán, E., Fuxa, M., Chong, W., Martinez, D., Novatchkova, M., Busslinger, M., & Skok, J. A. (2005). Locus “decontraction” and centromeric recruitment contribute to allelic exclusion of the immunoglobulin heavy-chain gene. Nature Immunology, 6(1), 31–41. https://doi.org/10.1038/ni1150 Skok, J. A. (2014). Taking a break from the lab: Can it really be done? Trends in Cell Biology, 24(12), 725–726. https://doi.org/10.1016/j.tcb.2014.09.002 Proudhon, C., Snetkova, V., Raviram, R., Lobry, C., Badri, S., Jiang, T., Hao, B., Trimarchi, T., Kluger, Y., Aifantis, I., Bonneau, R., & Skok, J. A. (2016). Active and Inactive Enhancers Cooperate to Exert Localized and Long-Range Control of Gene Regulation. Cell Reports, 15(10), 2159–2169. https://doi.org/10.1016/j.celrep.2016.04.087 Lhoumaud, P., Sethia, G., Izzo, F., Sakellaropoulos, T., Snetkova, V., Vidal, S., Badri, S., Cornwell, M., Di Giammartino, D. C., Kim, K.-T., Apostolou, E., Stadtfeld, M., Landau, D. A., & Skok, J. (2019). EpiMethylTag: Simultaneous detection of ATAC-seq or ChIP-seq signals with DNA methylation. Genome Biology, 20(1), 248. https://doi.org/10.1186/s13059-019-1853-6 Nishana, M., Ha, C., Rodriguez-Hernaez, J., Ranjbaran, A., Chio, E., Nora, E. P., Badri, S. B., Kloetgen, A., Bruneau, B. G., Tsirigos, A., & Skok, J. A. (2020). Defining the relative and combined contribution of CTCF and CTCFL to genomic regulation. Genome Biology, 21(1), 108. https://doi.org/10.1186/s13059-020-02024-0   Related Episodes Identification of Functional Elements in the Genome (Bing Ren) Spatial Organization of the Human Genome (Wendy Bickmore) Chromatin Organization (Susan Gasser)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

18 Marras 202142min

In this episode of the Epigenetics Podcast, we caught up with Marieke Oudelaar from the Max Planck Institute for Biophysical Chemistry to talk about her work on chromatin organization during development and disease. Marieke Oudelaar and her team focus on on developing high-resolution Chromosome Conformation Capture (3C) based techniques, like low-input Capture-C, Tri-C, and Tiled-C. Those techniques are then used in combination with other genomic techniques, genetic perturbations, and computational approaches to investigate the 3D structure of chromatin in development and disease. The team focused on the interplay between genome organisation and regulation during mammalian differentiation, and how perturbations in these processes contribute to human disease, including cancer.   References Oudelaar, A. M., Davies, J. O. J., Downes, D. J., Higgs, D. R., & Hughes, J. R. (2017). Robust detection of chromosomal interactions from small numbers of cells using low-input Capture-C. Nucleic Acids Research, 45(22), e184–e184. https://doi.org/10.1093/nar/gkx1194 Oudelaar, A. M., Davies, J. O. J., Hanssen, L. L. P., Telenius, J. M., Schwessinger, R., Liu, Y., Brown, J. M., Downes, D. J., Chiariello, A. M., Bianco, S., Nicodemi, M., Buckle, V. J., Dekker, J., Higgs, D. R., & Hughes, J. R. (2018). Single-allele chromatin interactions identify regulatory hubs in dynamic compartmentalized domains. Nature Genetics, 50(12), 1744–1751. https://doi.org/10.1038/s41588-018-0253-2 Oudelaar, A. M., Beagrie, R. A., Gosden, M., de Ornellas, S., Georgiades, E., Kerry, J., Hidalgo, D., Carrelha, J., Shivalingam, A., El-Sagheer, A. H., Telenius, J. M., Brown, T., Buckle, V. J., Socolovsky, M., Higgs, D. R., & Hughes, J. R. (2020). Dynamics of the 4D genome during in vivo lineage specification and differentiation. Nature Communications, 11(1), 2722. https://doi.org/10.1038/s41467-020-16598-7 Aljahani, A., Hua, P., Karpinska, M. A., Quililan, K., Davies, J. O. J., & Oudelaar, A. M. (2021). Analysis of sub-kilobase chromatin topology reveals nano-scale regulatory interactions with variable dependence on cohesin and CTCF [Preprint]. Genomics. https://doi.org/10.1101/2021.08.10.455796   Related Episodes Hi-C and Three-Dimensional Genome Sequencing (Erez Lieberman Aiden) Unraveling Mechanisms of Chromosome Formation (Job Dekker) Ultraconserved Enhancers and Enhancer Redundancy (Diane Dickel)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

11 Marras 202138min

In this episode of the Epigenetics Podcast, we caught up with Camila dos Santos from Cold Spring Harbor Laboratories to talk about her work on enhancers and chromatin remodeling in mammary gland development. The lab of Camila dos Santos focuses on epigenetic regulation of normal and malignant mammary gland development. After puberty, the next significant phase in mammary gland development occurs in pregnancy, including changes in cellular function, and tissue reorganization. A different and as significant change in mammary glands occurs in the development breast cancer. Camila dos Santos and her lab were recently able to show that the reaction of mammary glands to a second pregnancy is different than to a first one, which is accompanied by changes in the DNA methylome of the cells. Furthermore, the lab studies the connection of pregnancy-induced epigenetic changes of chromatin and the risk of cancer development.   References dos Santos, C. O., Rebbeck, C., Rozhkova, E., Valentine, A., Samuels, A., Kadiri, L. R., Osten, P., Harris, E. Y., Uren, P. J., Smith, A. D., & Hannon, G. J. (2013). Molecular hierarchy of mammary differentiation yields refined markers of mammary stem cells. Proceedings of the National Academy of Sciences, 110(18), 7123–7130. https://doi.org/10.1073/pnas.1303919110 dos Santos, C. O., Dolzhenko, E., Hodges, E., Smith, A. D., & Hannon, G. J. (2015). An Epigenetic Memory of Pregnancy in the Mouse Mammary Gland. Cell Reports, 11(7), 1102–1109. https://doi.org/10.1016/j.celrep.2015.04.015 Feigman, M. J., Moss, M. A., Chen, C., Cyrill, S. L., Ciccone, M. F., Trousdell, M. C., Yang, S.-T., Frey, W. D., Wilkinson, J. E., & dos Santos, C. O. (2020). Pregnancy reprograms the epigenome of mammary epithelial cells and blocks the development of premalignant lesions. Nature Communications, 11(1), 2649. https://doi.org/10.1038/s41467-020-16479-z   Related Episodes Ultraconserved Enhancers and Enhancer Redundancy (Diane Dickel) Epigenetic Regulation of Stem Cell Self-Renewal and Differentiation (Peggy Goodell) Cancer and Epigenetics (David Jones)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

28 Loka 202137min

In this episode of the Epigenetics Podcast, we caught up with Marnie Blewitt from the Walter and Eliza Hall Institute of Medical Research to talk about her work on the role of SMCHD1 in Development and Disease. The Laboratory of Marnie Blewitt focuses finding inhibitors or activators for the epigenetic regulator SMCHD1. Marnie Blewitt identified and characterized this protein during her PhD and the findings were published in 2008 in Nature Genetics. Since then, she and her team were able to investigate the function of this protein further. By doing so, they showed the involvement of SMCHD1 in cancer and several other diseases. Currently the lab is screening for small molecules that can act as inhibitors or activators of SMCHD1 the former as potential treatments for facioscapulohumeral muscular dystrophy, the latter for Prader Willi and Schaaf-Yang syndromes, both of which have no current targeted treatments.   References Blewitt, M. E., Gendrel, A.-V., Pang, Z., Sparrow, D. B., Whitelaw, N., Craig, J. M., Apedaile, A., Hilton, D. J., Dunwoodie, S. L., Brockdorff, N., Kay, G. F., & Whitelaw, E. (2008). SmcHD1, containing a structural-maintenance-of-chromosomes hinge domain, has a critical role in X inactivation. Nature Genetics, 40(5), 663–669. https://doi.org/10.1038/ng.142 Leong, H. S., Chen, K., Hu, Y., Lee, S., Corbin, J., Pakusch, M., Murphy, J. M., Majewski, I. J., Smyth, G. K., Alexander, W. S., Hilton, D. J., & Blewitt, M. E. (2013). Epigenetic Regulator Smchd1 Functions as a Tumor Suppressor. Cancer Research, 73(5), 1591–1599. https://doi.org/10.1158/0008-5472.CAN-12-3019 Gordon, C. T., Xue, S., Yigit, G., Filali, H., Chen, K., Rosin, N., Yoshiura, K., Oufadem, M., Beck, T. J., McGowan, R., Magee, A. C., Altmüller, J., Dion, C., Thiele, H., Gurzau, A. D., Nürnberg, P., Meschede, D., Mühlbauer, W., Okamoto, N., … Reversade, B. (2017). De novo mutations in SMCHD1 cause Bosma arhinia microphthalmia syndrome and abrogate nasal development. Nature Genetics, 49(2), 249–255. https://doi.org/10.1038/ng.3765   Related Episodes Epigenetics and X-Inactivation (Edith Heard) Biophysical Modeling of 3-D Genome Organization (Leonid Mirny) Unraveling Mechanisms of Chromosome Formation (Job Dekker)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

14 Loka 202130min

In this episode of the Epigenetics Podcast, we caught up with Efrat Shema from the Weizmann Institute of Science to talk about her work on Single Molecule Imaging of chromatin, and the analysis of nucleosomes circulating in plasma. In ChIP-Seq experiments the peak you get as a read out represents an average over, most often, millions of cells. Furthermore, one often does not know if that peak represents one or more than one nucleosome. If you then want to study multiple marks at the same time, the question remains: do those modifications occur at the same time, in the same cell? The Laboratory of Efrat Shema works on answering those questions by developing methods to study the modification patterns on single nucleosomes with single molecule imaging. With that it is possible to study single nucleosomes in a high throughout manner to identify the modifications they are decorated with. A subsequent sequencing step makes it possible to identify the genomic location of that nucleosome.   References Shema, E., Bernstein, B. E., & Buenrostro, J. D. (2019). Single-cell and single-molecule epigenomics to uncover genome regulation at unprecedented resolution. Nature Genetics, 51(1), 19–25. https://doi.org/10.1038/s41588-018-0290-x Shema, E., Jones, D., Shoresh, N., Donohue, L., Ram, O., & Bernstein, B. E. (2016). Single-molecule decoding of combinatorially modified nucleosomes. Science, 352(6286), 717–721. https://doi.org/10.1126/science.aad7701 Shema, E., Kim, J., Roeder, R. G., & Oren, M. (2011). RNF20 Inhibits TFIIS-Facilitated Transcriptional Elongation to Suppress Pro-oncogenic Gene Expression. Molecular Cell, 42(4), 477–488. https://doi.org/10.1016/j.molcel.2011.03.011 Shema, E., Tirosh, I., Aylon, Y., Huang, J., Ye, C., Moskovits, N., Raver-Shapira, N., Minsky, N., Pirngruber, J., Tarcic, G., Hublarova, P., Moyal, L., Gana-Weisz, M., Shiloh, Y., Yarden, Y., Johnsen, S. A., Vojtesek, B., Berger, S. L., & Oren, M. (2008). The histone H2B-specific ubiquitin ligase RNF20/hBRE1 acts as a putative tumor suppressor through selective regulation of gene expression. Genes & Development, 22(19), 2664–2676. https://doi.org/10.1101/gad.1703008   Related Episodes ATAC-Seq, scATAC-Seq and Chromatin Dynamics in Single-Cells (Jason Buenrostro) Investigating the Dynamics of Epigenetic Plasticity in Cancer with Single Cell Technologies (Céline Vallot) The Past, Present, and Future of Epigenetics (Joe Fernandez, founder of Active Motif)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

30 Syys 202139min

In this episode of the Epigenetics Podcast, we caught up with Serena Sanulli from Stanford University to talk about her work on Heterochromatin Protein 1 (HP1), the structure of chromatin on the atomic-scale and the meso-scale, and phase separation. The Laboratory of Serena Sanulli is interested in finding connections between changes that happen on the nucleosomal level and the resulting impact on chromatin conformation on the meso-scale. They combine methods like NMR and Hydrogen-Deuterium Exchange-MS with Cell Biology and Genetics. This enables them to dissect how cells use the diverse biophysical properties of chromatin to regulate gene expression across length and time scales. A second focus of the lab is HP1, which interacts with the nucleosome and changes its conformation, enabling the compaction of the genome into heterochromatin, effectively silencing genes in that region. A high concentration of HP1 leads to the phenomenon of phase separation in the nucleus, which the Sanulli lab is now investigating.   References Sanulli, S., Justin, N., Teissandier, A., Ancelin, K., Portoso, M., Caron, M., Michaud, A., Lombard, B., da Rocha, S. T., Offer, J., Loew, D., Servant, N., Wassef, M., Burlina, F., Gamblin, S. J., Heard, E., & Margueron, R. (2015). Jarid2 Methylation via the PRC2 Complex Regulates H3K27me3 Deposition during Cell Differentiation. Molecular Cell, 57(5), 769–783. https://doi.org/10.1016/j.molcel.2014.12.020 Sanulli, S., Trnka, M. J., Dharmarajan, V., Tibble, R. W., Pascal, B. D., Burlingame, A. L., Griffin, P. R., Gross, J. D., & Narlikar, G. J. (2019). HP1 reshapes nucleosome core to promote phase separation of heterochromatin. Nature, 575(7782), 390–394. https://doi.org/10.1038/s41586-019-1669-2 Sanulli, S., & Narlikar, G. J. (2021). Generation and Biochemical Characterization of Phase‐Separated Droplets Formed by Nucleic Acid Binding Proteins: Using HP1 as a Model System. Current Protocols, 1(5). https://doi.org/10.1002/cpz1.109   Related Episodes Transcription and Polycomb in Inheritance and Disease (Danny Reinberg) Heterochromatin and Phase Separation (Gary Karpen)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

16 Syys 202131min

In this episode of the Epigenetics Podcast, we caught up with Catherine Jensen Peña from Princeton University to talk about her work on early life stress and its effects on behavior. The Laboratory of Catherine Peña focuses on how early life experiences are encoded and maintained into adulthood, with a long-lasting impact on behavior. Recent work showed, that child maltreatment and other forms of early life stress increase the lifetime risk of depression and other mood, anxiety, and drug disorders by 2-4 fold. The Peña Lab uses genome wide approaches to investigate key brain regions with a two-hit stress model. Using RNA-Seq, the Peña Lab has shown that depression-like gene expression patterns are programmed by early life stress, similar to observations in mice exhibiting depression-like behavior after adult stress and are visible even before behavioral changes. Furthermore, latent and unique transcriptional responses to adult stress among a subset of genes is programmed by early life stress. The role of chromatin modifications in regulating these processes are investigated using state of the art technologies like Mod-Spec or ATAC-Seq.   References Kronman, H., Torres-Berrío, A., Sidoli, S., Issler, O., Godino, A., Ramakrishnan, A., Mews, P., Lardner, C. K., Parise, E. M., Walker, D. M., van der Zee, Y. Y., Browne, C. J., Boyce, B. F., Neve, R., Garcia, B. A., Shen, L., Peña, C. J., & Nestler, E. J. (2021). Long-term behavioral and cell-type-specific molecular effects of early life stress are mediated by H3K79me2 dynamics in medium spiny neurons. Nature Neuroscience, 24(5), 667–676. https://doi.org/10.1038/s41593-021-00814-8 Peña, C. J., Smith, M., Ramakrishnan, A., Cates, H. M., Bagot, R. C., Kronman, H. G., Patel, B., Chang, A. B., Purushothaman, I., Dudley, J., Morishita, H., Shen, L., & Nestler, E. J. (2019). Early life stress alters transcriptomic patterning across reward circuitry in male and female mice. Nature Communications, 10(1), 5098. https://doi.org/10.1038/s41467-019-13085-6 Peña, C. J., Kronman, H. G., Walker, D. M., Cates, H. M., Bagot, R. C., Purushothaman, I., Issler, O., Loh, Y.-H. E., Leong, T., Kiraly, D. D., Goodman, E., Neve, R. L., Shen, L., & Nestler, E. J. (2017). Early life stress confers lifelong stress susceptibility in mice via ventral tegmental area OTX2. Science, 356(6343), 1185–1188. https://doi.org/10.1126/science.aan4491   Related Episodes Nutriepigenetics: The Effects of Diet on Behavior (Monica Dus) The Role of Small RNAs in Transgenerational Inheritance in C. elegans (Oded Rechavi) Epigenetic Influence on Memory Formation and Inheritance (Isabelle Mansuy)   Contact Active Motif on Twitter Epigenetics Podcast on Twitter Active Motif on LinkedIn Active Motif on Facebook Email: podcast@activemotif.com

2 Syys 202136min