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, Cellular differentiation, Transcription factor
Papers published on a yearly basis
Papers
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TL;DR: A rapid and convenient electroporation method for both gain- and loss-of-function studies in vivo and in vitro in the rodent retina is reported, which led to photoreceptor phenotypes similar to those of the corresponding knockout mice.
Abstract: The large number of candidate genes made available by comprehensive genome analysis requires that relatively rapid techniques for the study of function be developed. Here, we report a rapid and convenient electroporation method for both gain- and loss-of-function studies in vivo and in vitro in the rodent retina. Plasmid DNA directly injected into the subretinal space of neonatal rodent pups was taken up by a significant fraction of exposed cells after several pulses of high voltage. With this technique, GFP expression vectors were efficiently transfected into retinal cells with little damage to the operated pups. Transfected GFP allowed clear visualization of cell morphologies, and the expression persisted for at least 50 days. DNA-based RNA interference vectors directed against two transcription factors important in photoreceptor development led to photoreceptor phenotypes similar to those of the corresponding knockout mice. Reporter constructs carrying retinal cell type-specific promoters were readily introduced into the retina in vivo, where they exhibited the appropriate expression patterns. Plasmid DNA was also efficiently transfected into retinal explants in vitro by high-voltage pulses.
970 citations
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TL;DR: A RIP-seq method is developed to capture thePRC2 transcriptome and identify a genome-wide pool of >9000 PRC2-interacting RNAs in embryonic stem cells, some of which may be used as biomarkers and therapeutic targets for human disease.
970 citations
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TL;DR: The results indicate that electrically coupled cardiac muscle regenerates after resection injury, primarily through activation and expansion of cardiomyocyte populations, which have implications for promoting regeneration of the injured human heart.
Abstract: Recent studies indicate that mammals, including humans, maintain some capacity to renew cardiomyocytes throughout postnatal life. Yet, there is little or no significant cardiac muscle regeneration after an injury such as acute myocardial infarction. By contrast, zebrafish efficiently regenerate lost cardiac muscle, providing a model for understanding how natural heart regeneration may be blocked or enhanced. In the absence of lineage-tracing technology applicable to adult zebrafish, the cellular origins of newly regenerated cardiac muscle have remained unclear. Using new genetic fate-mapping approaches, here we identify a population of cardiomyocytes that become activated after resection of the ventricular apex and contribute prominently to cardiac muscle regeneration. Through the use of a transgenic reporter strain, we found that cardiomyocytes throughout the subepicardial ventricular layer trigger expression of the embryonic cardiogenesis gene gata4 within a week of trauma, before expression localizes to proliferating cardiomyocytes surrounding and within the injury site. Cre-recombinase-based lineage-tracing of cells expressing gata4 before evident regeneration, or of cells expressing the contractile gene cmlc2 before injury, each labelled most cardiac muscle in the ensuing regenerate. By optical voltage mapping of surface myocardium in whole ventricles, we found that electrical conduction is re-established between existing and regenerated cardiomyocytes between 2 and 4 weeks post-injury. After injury and prolonged fibroblast growth factor receptor inhibition to arrest cardiac regeneration and enable scar formation, experimental release of the signalling block led to gata4 expression and morphological improvement of the injured ventricular wall without loss of scar tissue. Our results indicate that electrically coupled cardiac muscle regenerates after resection injury, primarily through activation and expansion of cardiomyocyte populations. These findings have implications for promoting regeneration of the injured human heart.
969 citations
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TL;DR: By comparing constitutional and tumour tissue genotypes of insulinomas from a pair of brothers who had inherited MEN-1 from their mother, it is shown that oncogenesis in these cases involves unmasking of a recessive mutation at this locus.
Abstract: Multiple endocrine neoplasia type 1 (MEN-1) is a predisposition to hyperplasia of the parathyroid glands, and to hyperplasia or tumours of the anterior pituitary and the endocrine pancreas, and is inherited as an autosomal dominant trait. Here we map the MEN-1 locus to chromosome 11 by family studies, and demonstrate tight linkage with the human muscle phosphorylase gene. By comparing constitutional and tumour tissue genotypes of insulinomas from a pair of brothers who had inherited MEN-1 from their mother, we have shown that oncogenesis in these cases involves unmasking of a recessive mutation at this locus.
968 citations
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TL;DR: It is found that even in the genetic absence of T reg cells, a nonmyeloablative regimen substantially augmented CD8+ T cell reactivity to self-tissue and tumor, and the restricted availability of homeostatic cytokines can be a contributing factor to peripheral tolerance, as well as a limiting resource for the effectiveness of tumor-specific T cells.
Abstract: Depletion of immune elements before adoptive cell transfer (ACT) can dramatically improve the antitumor efficacy of transferred CD8 + T cells, but the specific mechanisms that contribute to this enhanced immunity remain poorly defined. Elimination of CD4 + CD25 + regulatory T (T reg) cells has been proposed as a key mechanism by which lymphodepletion augments ACT-based immunotherapy. We found that even in the genetic absence of T reg cells, a nonmyeloablative regimen substantially augmented CD8 + T cell reactivity to self-tissue and tumor. Surprisingly, enhanced antitumor efficacy and autoimmunity was caused by increased function rather than increased numbers of tumor-reactive T cells, as would be expected by homeostatic mechanisms. The γ C cytokines IL-7 and IL-15 were required for augmenting T cell functionality and antitumor activity. Removal of γ C cytokine–responsive endogenous cells using antibody or genetic means resulted in the enhanced antitumor responses similar to those seen after nonmyeloablative conditioning. These data indicate that lymphodepletion removes endogenous cellular elements that act as sinks for cytokines that are capable of augmenting the activity of self/tumor-reactive CD8 + T cells. Thus, the restricted availability of homeostatic cytokines can be a contributing factor to peripheral tolerance, as well as a limiting resource for the effectiveness of tumor-specific T cells.
968 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 |