| EMBL - Sapienza Lecture | Friday, 31 January 2020, 11:00Add to calendarDaddy issues: paternal effects of environment on offspring in mammalsOliver Rando, University of Massachusetts Medical School, Worcester, MA, USA, USAHost: Matthieu Boulard / Irene BozzoniSapienza Università di Roma - Aula Odeion - Museo dell'Arte Classica - P.le Aldo Moro, 5 - Roma, EMBL Rome |
| EMBL Distinguished Visitor Lecture | Friday, 6 March 2020, 10:00Add to calendarHow do neurons compute the direction of motion?Alexander Borst, Max-Planck-Institute of Neurobiology, Martinsried, Germany, GermanyHost: Hiroki AsariCNR Seminar Room, EMBL Rome Abstract: Detecting the direction of image motion is important for visual navigation, predator avoidance and prey capture, and thus essential for the survival of all animals that have eyes. However, the direction of motion is not explicitly represented at the level of the photoreceptors: it rather needs to be computed by subsequent neural circuits, involving a comparison of the signals from neighboring photoreceptors over time. The exact nature of this process represents a classic example of neural computation and has been a longstanding question in the field. Only recently, much progress has been made in the fruit fly Drosophila by genetically targeting individual neuron types to block, activate or record from them. Our results obtained this way indicate that the local direction of motion is computed in two parallel ON and OFF pathways. Within each pathway, a retinotopic array of four direction-selective T4 (ON) and T5 (OFF) cells represents the four Cartesian components of local motion vectors (leftward, rightward, upward, downward). Since none of the presynaptic neurons turns out to be directionally selective, direction selectivity first emerges within T4 and T5 cells. Our present research focuses on the cellular and biophysical mechanisms by which this important visual cue is computed in these neurons. |
| Science and Society | Friday, 13 March 2020, 11:00Add to calendarTo be announcedAlessandra Falcucci, FAO, Rome, ItalyHost: Cornelius Gross / Lucia von BredowCNR Seminar Room, EMBL Rome |
| EMBL Distinguished Visitor Lecture | Friday, 3 April 2020, 10:00Add to calendarTo be announcedDirk Schübeler, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland, SwitzerlandHost: Mathieu BoulardCNR Seminar Room, EMBL Rome |
| EMBL - Sapienza Lecture | Friday, 24 April 2020, 11:00Add to calendarDiscovery of a sensory system in the vertebrate spinal cord: roles in development, postural control and innate immunityClaire Wyart, Institut du Cerveau et de la Moelle Epiniere CHU, Paris, France, , FranceHost: Cornelius Gross / Andrea MeleSapienza Università di Roma - Aula Odeion - Museo dell'Arte Classica - P.le Aldo Moro, 5 - Roma, EMBL Rome Abstract: Discovery of a sensory system in the vertebrate spinal cord: roles in development, postural control and innate immunity
Andrew Prendergast, Adeline Orts Del Immagine, Yasmine Cantaut-Belarif, Laura Desban, Lydia Djenoune, Urs Böhm, Kevin Fidelin, Jenna Sternberg, Pierre-Luc Bardet, Claire Wyart
The cerebrospinal fluid (CSF) is a complex solution circulating around the brain and spinal cord. Recent evidence indicate that the development of the nervous system is strongly influenced by the content and flow of the CSF. Yet, it is not known whether neuronal activity changes as a function of the physico-chemical properties of the CSF. We identify that CSF-contacting neurons by their location at the interface between the CSF and the nervous system were in ideal position to sense CSF cues, to relay information to local networks and to regulate CSF content by secretion. By combining electrophysiology, optogenetics and calcium imaging in vivo in zebrafish larvae, we demonstrate that neurons contacting the CSF detect local bending of the spinal cord and in turn feedback GABAergic inhibition to multiple interneurons driving locomotion and posture in the spinal cord and hindbrain. This GABAergic feedback modulates target in a state-dependent manner, depending on the fact that the animal is at rest or actively moving at a define speed. Behavioral analysis of animals deprived of this sensory pathway reveals differential effects on speed for slow and fast regimes, as well as impairments in the control of posture during active locomotion. Our work first sheds light on the cellular and network mechanisms enabling sensorimotor integration of mechanical and chemical cues from the CSF onto motor circuits controlling locomotion and posture in the spinal cord. We will present converging evidence that this interoceptive sensory pathway is involved in development, with the formation and maintenance of spine curvature, as well as innate immunity via the detection and combat of pathogens intruding the CSF during bacterial meningitis.
References
Mirat et al., Frontiers in Neural Circuits 2013.
Djenoune et al., Frontiers in Neuroanatomy 2014.
Fidelin et al., Current Biology 2015.
Böhm, Prendergast et al., Nature Communications 2016.
Hernandez et al., Nature Communications 2016.
Sternberg, Severi et al., Current Biology 2016.
Hubbard et al., Current Biology 2016.
Djenoune et al., Scientific Reports 2017.
Knafo, Fidelin et al., eLife 2017.
Cantaut-Belarif et al., Current Biology 2018.
Sternberg et al., Nature Communications 2018.
Severi et al., Scientific Reports 2018.
Prendergast et al., http://dx.doi.org/10.2139/ssrn.3404255
Thouvenin et al., in press.
Orts Del Immagine et al., in revision.
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| EMBL Distinguished Visitor Lecture | Friday, 15 May 2020, 10:00Add to calendarWhat Art can tell us about the BrainMargaret Livingstone, Harvard Medical School, Boston, MA, USA, , USAHost: Santiago Rompani CNR Seminar Room, EMBL Rome Abstract: Artists have been doing experiments on vision longer than neurobiologists. Some major works of art have provided insights as to how we see; some of these insights are so fundamental that they can be understood in terms of the underlying neurobiology. For example, artists have long realized that color and luminance can play independent roles in visual perception. Picasso said, "Colors are only symbols. Reality is to be found in luminance alone." This observation has a parallel in the functional subdivision of our visual systems, where color and luminance are processed by the evolutionarily newer, primate-specific What system, and the older, colorblind, Where (or How) system. Many techniques developed over the centuries by artists can be understood in terms of the parallel organization of our visual systems. I will explore how the segregation of color and luminance processing are the basis for why some Impressionist paintings seem to shimmer, why some op art paintings seem to move, some principles of Matisse's use of color, and how the Impressionists painted "air". Central and peripheral vision are distinct, and I will show how the differences in resolution across our visual field make the Mona Lisa's smile elusive, and produce a dynamic illusion in Pointillist paintings, Chuck Close paintings, and photomosaics. I will explore how artists have figured out important features about how our brains extract relevant information about faces and objects, and I will discuss why learning disabilities may be associated with artistic talent.
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| External Faculty Speaker | Thursday, 21 May 2020, 14:00Add to calendarEstablishment of the zygotic epigenome in DrosophilaNicola Iovino, Max Planck Institute of Immunobiology & Epigenetics, Freiburg, Germany, GermanyHost: Mathieu BoulardCNR Seminar Room, EMBL Rome Abstract: Fertilization occurs when the two gametes, after epigenetic reprogramming, fuse to produce a totipotent zygote. Although any defects in gametes reprogramming can cause infertility, the mechanisms underlying this process, remain poorly understood.
Our lab now focuses on understanding the epigenetic events contributing to the formation of functional gametes, to the establishment of totipotency and to the
conversion of the totipotent zygote s quiescent genome into a transcriptionally competent one.
We recently showed that H3K27me3 repressive histone mark is retained on postmeiotic oocytes and it is intergenerationally transmitted from the germline to the early embryo. The maternally inherited H3K27me3 regulates the activation of enhancers and lineage-specific genes during development. Thus, we suggest that H3K27me3 serve as a template of epigenetic memory that can be transferred through the maternal germline and instruct the developmental program of the next generation.
Selected references:
Skvortsova K., et al (2018) Functions and mechanisms of epigenetic inheritance in animals. Nat Rev Mol
Cell Biol. 19(12):774-790
Zenk F., et al. (2017) Germ line inherited H3K27me3 restricts enhancer function during maternal-tozygotic
transition. Science 6347, 212-216
Iovino N. (2014) Drosophila epigenome reorganization during oocyte differentiation and early
embryogenesis. Brief Funct Genomics 13, 246-253.
Iovino N., Ciabrelli F. and Cavalli G. (2013) PRC2 controls Drosophila oocyte cell fate by repressing
cell cycle genes. Dev Cell 26, 431-439. |
| EMBL - Sapienza Lecture | Friday, 22 May 2020, 11:00Add to calendarRNA modifications in gene expression controlRamesh Pillai, University of Geneva, Geneva, Switzerland, , SwitzerlandHost: Mathieu Boulard / Irene BozzoniCNR Seminar Room, EMBL Rome |
| EMBL - Sapienza Lecture | CANCELLED - Friday, 29 May 2020, 11:00Add to calendarAssembly and functions of ribonucleoprotein condensates in development and diseaseJernej Ule , Crick Institute, London, UK, United KingdomHost: Matthieu Boulard / Irene BozzoniSapienza Università di Roma - Aula Odeion - Museo dell'Arte Classica - P.le Aldo Moro, 5 - Roma, EMBL Rome |
| EMBL Distinguished Visitor Lecture | Friday, 18 September 2020, 10:00Add to calendarDNA methylation in development and disease.Alexander Meissner, Max Planck Institute for Molecular Genetics, Berlin, GermanyHost: Jamie HackettCNR Seminar Room, EMBL Rome |
| EMBL - Sapienza Lecture | Friday, 2 October 2020, 11:00Add to calendarEpigenetics of stress allostasis: somatic mechanisms for germ cell programming of offspring developmentTracy L. Bale, Center for Epigenetic Research in Child Health and Brain Development, University of Maryland School of Medicine, USAHost: Cornelius Gross / Andrea MeleSapienza Università di Roma - Aula Odeion - Museo dell'Arte Classica - P.le Aldo Moro, 5 - Roma, EMBL Rome Abstract: Epigenetics of stress allostasis: somatic mechanisms for germ cell programming of offspring development
Tracy L. Bale, J. Chan, C. Morgan, N.A. Leu, S. Ament, B. Garcia, M. Kane, C.N. Epperson
Parental lifetime exposures to perturbations such as stress, infection, malnutrition, and advanced age have been linked with an increased risk for offspring disease, including a strong association with neurodevelopmental disorders. Our studies have focused on identifying the causal biological mechanisms whereby information in the environment can be transmitted in sperm. In these studies, we demonstrate a causal role for somatic-to-germline transmission of stress information capable of altering fetal neurodevelopment via extracellular vesicles (EVs) in a preclinical model, and we further establish the translational potential of this model in a human cohort. We identified broad histone and transcriptomic alterations in mouse epididymal epithelial cells (EECs) in vivo, with corresponding persistent changes in miRNA and proteomic extracellular vesicle cargo secreted from pure caput EEC populations in vitro. In these studies, the transmission of paternal stress and changes in epigenetic marks only occur following a stress recovery period suggesting a cellular allostatic shift in chromatin programming. Using a transgenic approach, we demonstrated in vivo that the EEC glucocorticoid receptor, a central node of cellular stress mechanisms, serves a key role in this cellular programming where genetic knockdown of this receptor rescued the germline transmission of the offspring stress phenotype. We further established the causal involvement of EEC EVs utilizing intracytoplasmic sperm injection of caput sperm incubated with EVs secreted following stress treatment recovery. Translationally, we have examined similar stress programming changes in human sperm miRNA content. We utilized within and between human subject comparisons of sperm samples and neuropsychiatric perceived stress reports collected repeatedly over six months to identify a distinct miRNA expression pattern from subjects showing a post-stress recovery state.
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| Science and Society | Friday, 9 October 2020, 11:00Add to calendarUnderstanding urban environments in relation to population health Manuel Franco, University of Alcalá, Alcalá de Henares, Madrid, Spain, SpainHost: Lucia von Bredow / Cornelius GrossCNR Seminar Room, EMBL Rome |
