Anne Ephrussi | |
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Born | Paris | 15 September 1955
Education | Harvard, MIT (PhD 1983) |
Known for | Study of post-transcriptional regulation |
Parents |
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Awards | Chevalier de l’Ordre National du Mérite, France; Chevalier de la Légion d’Honneur, France [20]; Feldberg Prize |
Scientific career | |
Fields | Developmental and molecular biology |
Institutions | Harvard, Whitehead Institute, European Molecular Biology Laboratory |
Doctoral advisor | Susumu Tonegawa |
Other academic advisors | Thomas Maniatis, Ruth Lehmann |
Anne Ephrussi (born 15 September 1955 in Paris, France) is a French developmental and molecular biologist. Her research is focused on the study of post-transcriptional regulations such as mRNA localization and translation control in molecular biology as well as the establishment of polarity axes in cell and developmental biology. [1] She is director of the EMBL International Centre for Advanced Training (EICAT) program at the European Molecular Biology Laboratory (EMBL) [2] [3] since 2005 and served as head of the Developmental Biology Unit from 2007 to 2021.
Anne Ephrussi studied biology at Harvard University in the Department of Biochemistry and Molecular Biology from where she graduated in 1979. She continued to do her PhD at the Massachusetts Institute of Technology (MIT) in the group of Susumu Tonegawa where she received her doctoral degree in 1985. Ephrussi performed postdoctoral research at Harvard University in the lab of Thomas Maniatis from 1986 to 1989 and at the Whitehead Institute for Biomedical Research with Ruth Lehmann from 1989 to 1992. Since 1992, Anne Ephrussi has been a group leader at the European Molecular Biology Laboratory (EMBL). She became the head of EMBL International Centre for Advanced Training in 2005. [2] [4] She served as Associate Dean (1999 - 2005) and Dean (2005 - 2008) of Graduate Studies of the EMBL International PhD program and as head of the developmental biology unit (2007-2021). She is part of numerous international Scientific Advisory Boards and Panels, organizes international conferences and scientific meetings and evaluates research grant and fellowship applications for a variety of renowned funding bodies.
Anne Ephrussi has French and American citizenship. She is the daughter of Boris Ephrussi and Harriett Ephrussi-Taylor. [5] She lives in Heidelberg, is married and has one child.
With her research, Anne Ephrussi has contributed to the elucidation of the crucial role that spatial and temporal control of mRNA localization and translation play in oocyte development and cell polarity. [6]
Ephrussi established that oskar RNA is accumulated at and thereby defines the posterior pole of the Drosophila oocyte. [7] Aberrant localization and translation leads to germ cell formation defects and mispatterning during development. [8] Proper localization of oskar mRNA is ensured by concerted actions of the exon junction complex [9] [10] [11] and oskar's 3’ UTR [12] followed by a microtubule-based movement. During transport, translation of oskar is repressed by the RNA-binding protein Bruno, which is in turn released by the binding of activators (e.g. Orb) upon arrival at the posterior pole. [13] After proper localization, oskar RNA is translated and organizes germ plasm by recruiting other proteins such as Vasa. [14]
Her lab's current research continues to focus on spatial and temporal control of translation and which role ribonucleoprotein complexes (RNPs), cytoskeletal polarization and cytoskeletal motors play in RNA localization. Further, the roles of non-canonical RNA binding proteins in development as well as germ plasm assembly and function are investigated. These questions are tackled using a combination of genetics, biochemistry and a broad spectrum of cell bio logical and imaging approaches using the large Drosophila melanogaster oocyte as a model.
A germ cell is any cell that gives rise to the gametes of an organism that reproduces sexually. In many animals, the germ cells originate in the primitive streak and migrate via the gut of an embryo to the developing gonads. There, they undergo meiosis, followed by cellular differentiation into mature gametes, either eggs or sperm. Unlike animals, plants do not have germ cells designated in early development. Instead, germ cells can arise from somatic cells in the adult, such as the floral meristem of flowering plants.
An oocyte (, oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell, which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation.
Drosophila embryogenesis, the process by which Drosophila embryos form, is a favorite model system for genetics and developmental biology. The study of its embryogenesis unlocked the century-long puzzle of how development was controlled, creating the field of evolutionary developmental biology. The small size, short generation time, and large brood size make it ideal for genetic studies. Transparent embryos facilitate developmental studies. Drosophila melanogaster was introduced into the field of genetic experiments by Thomas Hunt Morgan in 1909.
The LIM kinases are a family of actin-binding kinases that phosphorylate members of the ADF/cofilin family of actin binding and filament severing proteins. The LIM kinase family is made up of two proteins: LIM kinase-1 (LIMK1) and LIM kinase-2 (LIMK2)
In developmental biology, the cells that give rise to the gametes are often set aside during embryonic cleavage. During development, these cells will differentiate into primordial germ cells, migrate to the location of the gonad, and form the germline of the animal.
Piwi-interacting RNA (piRNA) is the largest class of small non-coding RNA molecules expressed in animal cells. piRNAs form RNA-protein complexes through interactions with piwi-subfamily Argonaute proteins. These piRNA complexes are mostly involved in the epigenetic and post-transcriptional silencing of transposable elements and other spurious or repeat-derived transcripts, but can also be involved in the regulation of other genetic elements in germ line cells.
oskar is a gene required for the development of the Drosophila embryo. It defines the posterior pole during early embryogenesis. Its two isoforms, short and long, play different roles in Drosophila embryonic development. oskar was named after the main character from the Günter Grass novel The Tin Drum, who refuses to grow up.
In early Drosophila development, the embryo passes through thirteen nuclear divisions (karyokinesis) without cytokinesis, resulting in a multinucleate cell. Pole cells are the cells that form at the polar ends of the Drosophila egg, which begin the adult germ cells. Pole plasm functions to bud the pole cells, as well as restore fertilization, even when the cell was previously sterile.
Deleted in azoospermia-like is a protein that in humans is encoded by the DAZL gene.
Matthias Werner Hentze is a German scientist. He is the director of the European Molecular Biology Laboratory (EMBL), co-director of the Molecular Medicine Partnership Unit between EMBL and Heidelberg University, and Professor of Molecular Medicine at Heidelberg University.
Staufen is a protein product of a maternally expressed gene first identified in Drosophila melanogaster. The protein has been implicated in helping regulate genes important in determination of gradients that set up the anterior posterior axis such as bicoid and oskar. Staufen proteins, abbreviated Stau, are necessary for cell localization during the oogenesis and zygotic development. It is involved in targeting of the messenger RNA encoding these genes to the correct pole of the egg cell.
Vasa is an RNA binding protein with an ATP-dependent RNA helicase that is a member of the DEAD box family of proteins. The vasa gene is essential for germ cell development and was first identified in Drosophila melanogaster, but has since been found to be conserved in a variety of vertebrates and invertebrates including humans. The Vasa protein is found primarily in germ cells in embryos and adults, where it is involved in germ cell determination and function, as well as in multipotent stem cells, where its exact function is unknown.
Homeotic protein bicoid is encoded by the bcd maternal effect gene in Drosophilia. Homeotic protein bicoid concentration gradient patterns the anterior-posterior (A-P) axis during Drosophila embryogenesis. Bicoid was the first protein demonstrated to act as a morphogen. Although bicoid is important for the development of Drosophila and other higher dipterans, it is absent from most other insects, where its role is accomplished by other genes.
Ruth Lehmann is a developmental and cell biologist. She is the Director of the Whitehead Institute for Biomedical Research. She previously was affiliated with the New York University School of Medicine, where she was the Director of the Skirball Institute of Biomolecular Medicine, the Laura and Isaac Perlmutter Professor of Cell Biology, and the Chair of the Department of Cell Biology. Her research focuses on germ cells and embryogenesis.
Smaug is a RNA-binding protein in Drosophila that helps in maternal to zygotic transition (MZT). The protein is named after the fictional character Smaug, the dragon in J.R.R. Tolkien's 1937 novel The Hobbit. The MZT ends with the midblastula transition (MBT), which is defined as the first developmental event in Drosophila that depends on zygotic mRNA. In Drosophila, the initial developmental events are controlled by maternal mRNAs like Hsp83, nanos, string, Pgc, and cyclin B mRNA. Degradation of these mRNAs, which is expected to terminate maternal control and enable zygotic control of embryogenesis, happens at interphase of nuclear division cycle 14. During this transition smaug protein targets the maternal mRNA for destruction using miRs. Thus activating the zygotic genes. Smaug is expected to play a role in expression of three miRNAs – miR-3, miR-6, miR-309 and miR-286 during MZT in Drosophila. Among them smaug dependent expression of miR-309 is needed for destabilization of 410 maternal mRNAs. In smaug mutants almost 85% of maternal mRNA is found to be stable. Smaug also binds to 3′ untranslated region (UTR) elements known as SMG response elements (SREs) on nanos mRNA and represses its expression by recruiting a protein called Cup(an eIF4E-binding protein that blocks the binding of eIF4G to eIF4E). There after it recruits deadenylation complex CCR4-Not on to the nanos mRNA which leads to deadenylation and subsequent decay of the mRNA. It is also found to be involved in degradation and repression of maternal Hsp83 mRNA by recruiting CCR4/POP2/NOT deadenylase to the mRNA. The human Smaug protein homologs are SAMD4A and SAMD4B.
Elisa Izaurralde was an Uruguayan biochemist and molecular biologist. She served as Director and Scientific Member of the Department of Biochemistry at the Max Planck Institute for Developmental Biology in Tübingen from 2005 until her death in 2018. In 2008, she was awarded the Gottfried Wilhelm Leibniz Prize, shared with Elena Conti, for "fundamental new insights into intracellular RNA transport and RNA metabolism". Together with Conti, she helped characterize proteins important for exporting mRNA out of the nucleus and later in her career she helped elucidate mechanisms of mRNA silencing, translational repression, and mRNA decay.
Melina Schuh is a German biochemist and Director at the Max Planck Institute for Multidisciplinary Sciences. She is known for her work on meiosis in mammalian oocytes, for her studies on the mechanisms leading to the age-related decline in female fertility, and for the development of the Trim-Away protein depletion method.
Marie A. DiBerardino was an American biologist, specializing in developmental biology and genetics. She is known, with Robert William Briggs and Thomas Joseph King, as a pioneer in amphibian cloning.
Eileen E. M. Furlong is an Irish molecular biologist working in the fields of transcription, chromatin biology, developmental biology and genomics. She is known for her work in understanding how the genome is regulated, in particular to how developmental enhancers function, how they interact within three dimensional chromatin topologies and how they drive cell fate decisions during embryogenesis. She is Head of the Department of Genome Biology at the European Molecular Biology Laboratory (EMBL). Furlong was elected a member of the European Molecular Biology Organization (EMBO) in 2013, the Academia Europaea in 2016 and to EMBO’s research council in 2018.
Elizabeth Gavis is an American biologist who is the Damon B. Pfeiffer Professor of Life Sciences, at Princeton University. Gavis served as the President of the North American Drosophila Board of Directors in 2011.