Institution
Howard Hughes Medical Institute
Nonprofit•Chevy Chase, Maryland, United States•
About: Howard Hughes Medical Institute is a nonprofit organization based out in Chevy Chase, Maryland, United States. It is known for research contribution in the topics: Gene & RNA. The organization has 20371 authors who have published 34677 publications receiving 5247143 citations. The organization is also known as: HHMI & hhmi.org.
Topics: Gene, RNA, Population, Receptor, Cellular differentiation
Papers published on a yearly basis
Papers
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TL;DR: The construction of the piRNA system in the restricted developmental window in which methylation patterns are set during mammalian embryogenesis is examined, finding robust expression of two Piwi family proteins, MIWI2 and MILI.
1,080 citations
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TL;DR: It is shown that the intrinsic plasticity of the protein is a key characteristic of catalysis, and the pre-existence of collective dynamics in enzymes before catalysis is a common feature of biocatalysts and that proteins have evolved under synergy pressure between structure and dynamics.
Abstract: A unique feature of chemical catalysis mediated by enzymes is that the catalytically reactive atoms are embedded within a folded protein. Although current understanding of enzyme function has been focused on the chemical reactions and static three-dimensional structures, the dynamic nature of proteins has been proposed to have a function in catalysis. The concept of conformational substates has been described; however, the challenge is to unravel the intimate linkage between protein flexibility and enzymatic function. Here we show that the intrinsic plasticity of the protein is a key characteristic of catalysis. The dynamics of the prolyl cis-trans isomerase cyclophilin A (CypA) in its substrate-free state and during catalysis were characterized with NMR relaxation experiments. The characteristic enzyme motions detected during catalysis are already present in the free enzyme with frequencies corresponding to the catalytic turnover rates. This correlation suggests that the protein motions necessary for catalysis are an intrinsic property of the enzyme and may even limit the overall turnover rate. Motion is localized not only to the active site but also to a wider dynamic network. Whereas coupled networks in proteins have been proposed previously, we experimentally measured the collective nature of motions with the use of mutant forms of CypA. We propose that the pre-existence of collective dynamics in enzymes before catalysis is a common feature of biocatalysts and that proteins have evolved under synergistic pressure between structure and dynamics.
1,080 citations
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TL;DR: It is found that trial-to-trial variability in neuronal signals was correlated with the choices the monkey made, and this is consistent with the idea that neuronal signals in MT are used by the monkey to determine the direction of stimulus motion.
Abstract: We have previously documented the exquisite motion sensitivity of neurons in extrastriate area MT by studying the relationship between their responses and the direction and strength of visual motion signals delivered to their receptive fields. These results suggested that MT neurons might provide the signals supporting behavioral choice in visual discrimination tasks. To approach this question from another direction, we have now studied the relationship between the discharge of MT neurons and behavioral choice, independently of the effects of visual stimulation. We found that trial-to-trial variability in neuronal signals was correlated with the choices the monkey made. Therefore, when a directionally selective neuron in area MT fires more vigorously, the monkey is more likely to make a decision in favor of the preferred direction of the cell. The magnitude of the relationship was modest, on average, but was highly significant across a sample of 299 cells from four monkeys. The relationship was present for all stimuli (including those without a net motion signal), and for all but the weakest responses. The relationship was reduced or eliminated when the demands of the task were changed so that the directional signal carried by the cell was less informative. The relationship was evident within 50 ms of response onset, and persisted throughout the stimulus presentation. On average, neurons that were more sensitive to weak motion signals had a stronger relationship to behavior than those that were less sensitive. These observations are consistent with the idea that neuronal signals in MT are used by the monkey to determine the direction of stimulus motion. The modest relationship between behavioral choice and the discharge of any one neuron, and the prevalence of the relationship across the population, make it likely that signals from many neurons are pooled to form the data on which behavioral choices are based.
1,077 citations
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TL;DR: Insight is provided into Mg2+ homeostasis, the role of a tight junction protein in human disease is demonstrated, and an essential component of a selective paracellular conductance is identified.
Abstract: Epithelia permit selective and regulated flux from apical to basolateral surfaces by transcellular passage through cells or paracellular flux between cells. Tight junctions constitute the barrier to paracellular conductance; however, little is known about the specific molecules that mediate paracellular permeabilities. Renal magnesium ion (Mg2+) resorption occurs predominantly through a paracellular conductance in the thick ascending limb of Henle (TAL). Here, positional cloning has identified a human gene, paracellin-1 ( PCLN-1 ), mutations in which cause renal Mg2+ wasting. PCLN-1 is located in tight junctions of the TAL and is related to the claudin family of tight junction proteins. These findings provide insight into Mg2+homeostasis, demonstrate the role of a tight junction protein in human disease, and identify an essential component of a selective paracellular conductance.
1,077 citations
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Broad Institute1, Harvard University2, University of Tübingen3, Max Planck Society4, University of Mainz5, University of Washington6, University of California, Berkeley7, Massachusetts Institute of Technology8, Stockholm University9, University of Adelaide10, The Heritage Foundation11, National Museum of Natural History12, Sultan Qaboos University13, University of Edinburgh14, University of Costa Rica15, University of Antioquia16, Rambam Health Care Campus17, University of Pécs18, Al Akhawayn University19, Catholic University of the Sacred Heart20, University of Oxford21, Belgorod State University22, University of Toronto23, University of Buenos Aires24, University of Bern25, Russian Academy of Sciences26, Paul Sabatier University27, North-Eastern Federal University28, University of Chicago29, University of Arizona30, Stony Brook University31, University of Bergen32, Illumina33, Sofia Medical University34, Bashkir State University35, University of Cambridge36, Vilnius University37, Estonian Biocentre38, University of Strasbourg39, University College London40, Amgen41, Gladstone Institutes42, University of Tartu43, University of Oulu44, Muhimbili University of Health and Allied Sciences45, University of Palermo46, University of Tarapacá47, University of Chile48, Academy of Sciences of Uzbekistan49, Armenian National Academy of Sciences50, University of North Texas51, University of Santiago de Compostela52, University of Kharkiv53, Higher University of San Andrés54, Novosibirsk State University55, Leidos56, Lebanese American University57, University of Split58, University of Pennsylvania59, Banaras Hindu University60, Centre for Cellular and Molecular Biology61, Estonian Academy of Sciences62, Pompeu Fabra University63, Howard Hughes Medical Institute64
TL;DR: It is shown that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians; and early European farmers, who were mainly of Near Eastern origin but also harboured west Europeanhunter-gatherer related ancestry.
Abstract: We sequenced the genomes of a ∼7,000-year-old farmer from Germany and eight ∼8,000-year-old hunter-gatherers from Luxembourg and Sweden. We analysed these and other ancient genomes with 2,345 contemporary humans to show that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians, who contributed to both Europeans and Near Easterners; and early European farmers, who were mainly of Near Eastern origin but also harboured west European hunter-gatherer related ancestry. We model these populations' deep relationships and show that early European farmers had ∼44% ancestry from a 'basal Eurasian' population that split before the diversification of other non-African lineages.
1,077 citations
Authors
Showing all 20486 results
Name | H-index | Papers | Citations |
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Bert Vogelstein | 247 | 757 | 332094 |
Richard A. Flavell | 231 | 1328 | 205119 |
Steven A. Rosenberg | 218 | 1204 | 199262 |
Kenneth W. Kinzler | 215 | 640 | 243944 |
Robert J. Lefkowitz | 214 | 860 | 147995 |
Rob Knight | 201 | 1061 | 253207 |
Irving L. Weissman | 201 | 1141 | 172504 |
Ronald M. Evans | 199 | 708 | 166722 |
Francis S. Collins | 196 | 743 | 250787 |
Craig B. Thompson | 195 | 557 | 173172 |
Thomas C. Südhof | 191 | 653 | 118007 |
Joan Massagué | 189 | 408 | 149951 |
Stuart H. Orkin | 186 | 715 | 112182 |
John P. A. Ioannidis | 185 | 1311 | 193612 |
Eric R. Kandel | 184 | 603 | 113560 |