archive-edu.com » EDU » R » ROCKEFELLER.EDU

Total: 1631

Choose link from "Titles, links and description words view":

Or switch to "Titles and links view".
  • The making of a fat cell | Newswire
    lab showed that the tumor suppressor protein P53 binds to the TRAP80 subunit of the TRAP Mediator The TRAP Mediator also referred to as the human mediator belongs to a class of proteins called coactivators Previously scientists knew that these proteins were required for turning most genes on but until now it wasn t clear whether they also played cell specific roles in physiological processes such as adipogenesis Our findings suggest that different components of the human mediator regulate the formation of different cell types says Robert G Roeder head of the Laboratory of Biochemistry and Molecular Biology at Rockefeller and principal author of the Nature paper By allowing genes to be turned on in a cell specific manner this giant coactivator provides complex organisms such as humans with an added level of control over physiological processes says Roeder Cells are equal to sum of their proteins The various cell types constituting our bodies can be distinguished from one another by the specific proteins they produce For example fat cells manufacture an enzyme lipase to break down fats into smaller pieces when the body needs energy Muscle cells on the other hand produce an abundance of actin a protein that enables muscle contraction Thus when the body instructs a fibroblast to become a fat cell certain genes must be switched on such as the gene for lipase This vital life process of switching on or reading genes is called transcription the basis of which has been the subject of intense research in the Roeder lab for nearly 30 years Beginning with Roeder s initial discovery in 1969 of the human gene reading machines or RNA polymerases the Roeder lab has gone on to elucidate dozens of the proteins involved in switching genes on including the coactivator known as the human mediator Coactivators act together with two other classes of proteins activators and the general transcription machinery which includes RNA polymerase to turn genes on First activators bind to a specific stretch of DNA in frontof a given gene second bound activators recruit coactivators to the site then bound coactivators summon the general transcription machinery to the scene and finally the RNA polymerase begins reading the gene In essence then coactivators are like bridges that allow activators access to the general transcription machinery Rockefeller researchers led by Robert G Roeder discovered an indispensable protein in the fat making process Young mouse cells called fibroblasts normally mature into fat cells left containing lipid droplets red But without this protein called TRAP220 they cannot become fat cells But it has remained unclear whether coactivators in addition to their role as mandatory transcription proteins also function in a cell specific manner The report in Nature by Roeder and colleagues is one of the first to show that coactivators do indeed play a cell specific role in such physiological processes as adipogenesis Turning on fat program Previously scientists knew that some small fatty acid molecules could trigger the differentiation of an embryonic fibroblast into a

    Original URL path: http://newswire.rockefeller.edu/2002/05/28/the-making-of-a-fat-cell/ (2016-02-13)
    Open archived version from archive

  • TRAP220 | Newswire
    a red blood cell and carry oxygen to remote tissues Or might it become a liver cell and help rid the body of dangerous toxins Ultimately its destiny depends on a set of molecular signals that activate one of several possible cellular programs More Tags Robert G Roeder TRAP220 Search for Categories Science News Awards and Honors Campus News Grants Gifts Topics Video Archive 2015 2014 2013 2012 2011 more

    Original URL path: http://newswire.rockefeller.edu/tag/trap220/ (2016-02-13)
    Open archived version from archive

  • More Than Just Packaging, Histones Help Turn Genes On | Newswire
    of nucleosomes coil up further to form chromatin and even further to become the familiar X shaped chromosomes of human cells Hidden within this bundled mass of histones and DNA are the genes the cell s instructions for manufacturing its tens of thousands of proteins Therefore before the cell s machinery can read or as scientists say transcribe these genetic instructions and ultimately produce a protein of interest it must somehow open up or unfold the tightly wound chromatin Researchers in the laboratory of Robert G Roeder including Vikas B Palhan left and first author Woojin An report that the tails of histones previously thought to play only a passive role in repressing gene activity in fact act more like arms to switch genes on once the DNA is unpackaged But just how the cell s machinery knows which stretches of chromatin to break open and read and which to keep silent remains poorly understood Some scientists think that the key to regulating the activity of genes may lie with the very proteins that package them They propose that the tails of each histone become coded with different patterns of chemical tags and thus like a combination lock guarding a safe full of genes only permit access to those gene reading machines that somehow know the right histone code This code is not inherent to the histones themselves but is generated by other proteins in the nucleus Now as a twist to this developing story Roeder and collegues have discovered an entirely novel function for tails They show that these dangling ends in addition to repressing genes through chromatin folding also play an active role in switching genes on once the folding is reversed As counterintuitive as it may seem these tails seem to act both to block and to activate gene transcription says Roeder Previously scientists thought that the tails which unlike the rest of the histone extend from the compact body of the core nucleosome blocked transcription of a gene by causing chromatin folding Gene activation was thought to occur after the inhibitory effects of the tails were neutralized by the addition of a chemical tag a process called acetylation Histone tails are covered with positive charges and are therefore attracted to the negatively charged DNA says An Scientists believed that acetylation by masking the positive charges on tails caused the chromatin and underlying DNA to become less constricted by the histones and thus more receptive to unfolding To test this theory the researchers recreated coiled up chromatin in a test tube using engineered or recombinant histones and DNA a feat in itself considering that this type of biochemical tool had never before been successfully implemented They also showed that by adding a specific gene activator protein and a coactivator protein called p300 they could coax the chromatin to open up and permit transcription of a target gene Both a gene activator and a coactivator are required to switch on a target gene First the activator binds to

    Original URL path: http://newswire.rockefeller.edu/2002/05/13/more-than-just-packaging-histones-help-turn-genes-on/ (2016-02-13)
    Open archived version from archive

  • Rockefeller Receives Horwitz Prize for Pioneering Work on How Genes are Turned On and Off | Newswire
    causes tumors when it malfunctions By demonstrating how the function of key factors is altered Roeder s lab may help clarify the reasons for various growth and developmental abnormalities Ultimately it may lead researchers to control these processes and repair their pathological consequences As we become familiar with the fundamentals of how genes work we get closer to understanding diseases like cancer or viral infections like HIV says Roeder the university s Arnold and Mabel Beckman Professor and head of the Laboratory of Biochemistry and Molecular Biology Roeder s pioneering studies began when he was a graduate student at the University of Washington in the late 1960s My career started in the early days of understanding what vertebrate genes were and how they function Roeder says I first became interested in gene activation because this process is at the center of cell growth and differentiation Gene activation the process of transcription involves making an RNA copy of the gene from the DNA template Constructing this copy requires enzymes known as nuclear RNA polymerases which Roeder discovered while working in the laboratory of William J Rutter In a landmark paper published in 1969 he identified three polymerases which he designated I II and III responsible for reading out DNA and synthesizing the three different types of RNA Roeder also found three distinct groups of protein complexes called accessory factors that are essential for the individual RNA polymerases to recognize and copy particular classes of genes Roeder was also the first to identify the general factors proteins common to the transcription process for any gene for a number of different classes of genes including class II genes the ones that code for proteins in animal cells The general factor called TFIID is a key member of this group because it is the first to bind to the DNA control element called the TATA box a short section of DNA that determines where transcription starts on the gene RoederÕs lab showed that TFIID comprises a number of subcomponents specifically required for communication with the regulatory factors in addition to a small protein TBP that directly binds the TATA box and nucleates the assembly of RNA polymerase II and other general factors into a functional transcription complex The structure of TBP in association with DNA and general factor TFIIB was solved in landmark studies by Professor Stephen Burley an HHMI investigator RNA polymerases and related accessory proteins like TFIID are general factors Roeder says All genes use them But their functions on individual genes are dependent upon and regulated by proteins called activators that are specific to certain genes In the late 1970s Roeder developed systems in test tubes in which individual genes cloned by recombinant DNA techniques were transcribed precisely as in the normal cellular environment Roeder identified and cloned the first gene specific transcriptional regulatory factor called TFIIIA TFIIIA and similar proteins stimulate the copying of the target gene by the RNA polymerases and accessory factors Hundreds of these transcription activators have

    Original URL path: http://newswire.rockefeller.edu/2000/02/15/rockefeller-receives-horwitz-prize-for-pioneering-work-on-how-genes-are-turned-on-and-off/ (2016-02-13)
    Open archived version from archive

  • gene activation | Newswire
    the wrong gene at the wrong time More Tags gene activation RNA Seth Darst August 1 2003 Science News Rockefeller University researchers identify protein modules that read distinct gene silencing codes Since the time when humans first learned to record their thoughts in written form codes have kept sensitive information from prying eyes But conveying information through a code requires someone who can read it as well as write it The same is true for one of nature s methods for transmitting information that activates or silences a gene the histone code More Tags C David Allis gene activation gene silencing histone code February 15 2000 Awards and Honors Rockefeller Receives Horwitz Prize for Pioneering Work on How Genes are Turned On and Off Rockefeller University biochemist Robert Roeder Ph D received the Louisa Gross Horwitz Prize from Columbia University on Thursday Feb 3 The prize which Roeder shares with Robert Tjian Ph D of the Howard Hughes Medical Institute at the University of California at Berkeley and Pierre Chambon M D of the Université Louis Pasteur and the College de France honors scientists for outstanding basic research in biology or biochemistry More Tags gene activation Horwitz Prize Robert G

    Original URL path: http://newswire.rockefeller.edu/tag/gene-activation/ (2016-02-13)
    Open archived version from archive

  • Horwitz Prize | Newswire
    on Thursday Feb 3 The prize which Roeder shares with Robert Tjian Ph D of the Howard Hughes Medical Institute at the University of California at Berkeley and Pierre Chambon M D of the Université Louis Pasteur and the College de France honors scientists for outstanding basic research in biology or biochemistry More Tags gene activation Horwitz Prize Robert G Roeder Search for Categories Science News Awards and Honors Campus

    Original URL path: http://newswire.rockefeller.edu/tag/horwitz-prize/ (2016-02-13)
    Open archived version from archive

  • Rockefeller University Scientists Receive Prestigious Awards for Cancer Research | Newswire
    against many forms of cancer Over the past decade scientists have determined that p53 abnormalities are associated with more than half of all human cancers As a result p53 is a major focus of research in laboratories around the world Dr Levine pointed out that pure scientific curiosity paved the way for his later accomplishments When I was a graduate student at the University of Pennsylvania in the late 1960s I wanted to understand what caused cancer in human beings he said At that time we knew very little but one of the wonderful things about science is that you follow the leads and see where they can take you He expects to continue along the path of trying to find drugs that affect the mutations of p53 and sees his position at Rockefeller as an ideal place to start At Rockefeller we re engaged in cutting edge research and graduate education of the highest quality he said And we re right across the street from Sloan Kettering and New York Presbyterian Hospital Together we ll see the applications of our research by working with people who need our help Sloan Prize recipient Dr Roeder is an equally accomplished scientist A member of the National Academy of Sciences Dr Roeder s many awards include the American Chemical Society Eli Lilly Award in Biological Chemistry the Outstanding Investigator Award of the National Cancer Institute and the National Academy of Sciences U S Steel Award in Molecular Biology In conjunction with Dr Tjian he has also received the Passano Award and the Lewis S Rosenstiel Award for Distinguished Work in Basic Medical Sciences I began my career in the early days of understanding what vertebrate genes were and how they function Dr Roeder said I first became interested in gene activation because this process is at the center of cell growth and differentiation As we become familiar with the fundamentals of how genes work we get closer to understanding cancer The normal growth and specialization of animal cells and changes in these processes in various disease states such as cancer or virus infection result from programmed changes in the patterns of gene expression Gene expression is in turn regulated mainly at the level of transcription the process of making messenger RNA copies of the DNA sequences which comprise the genes For the past 25 years Dr Roeder s laboratory has pioneered biochemical studies of and made fundamental discoveries regarding transcriptional regulatory mechanisms in animal cells This includes the discovery of the enzymes RNA polymerases which directly copy DNA their associated helper factors and the first of many hundreds or thousands of gene and cell specific activators that regulate their function on target genes Dr Roeder explained that over the years he has become increasingly interested in the applications of his research We need not only to understand the mechanisms underlying normal gene expression but to relate these to important medical problems at the same time he said There is none greater than

    Original URL path: http://newswire.rockefeller.edu/1999/04/30/rockefeller-university-scientists-receive-prestigious-awards-for-cancer-research/ (2016-02-13)
    Open archived version from archive

  • Alfred P. Sloan Prize | Newswire
    Robert G Roeder Ph D professor and head of the Laboratory of Biochemistry and Molecular Biology have been recognized by the General Motors Cancer Research Foundation for their major contributions to cancer research More Tags Alfred P Sloan Prize Arnold J Levine Charles S Mott Prize General Motors Cancer Research Foundation Robert G Roeder Search for Categories Science News Awards and Honors Campus News Grants Gifts Topics Video Archive 2015

    Original URL path: http://newswire.rockefeller.edu/tag/alfred-p-sloan-prize/ (2016-02-13)
    Open archived version from archive