生物谷報(bào)道：很多遺傳疾病是由一個(gè)信使RNA（mRNA）向蛋白質(zhì)內(nèi)轉(zhuǎn)錄過(guò)程中的過(guò)早終止造成的，肌營(yíng)養(yǎng)不良癥就是這樣一種疾病?，F(xiàn)在，Welch等人報(bào)告,，一個(gè)名為PTC124的小分子能使這一轉(zhuǎn)錄機(jī)器繞開(kāi)會(huì)引起過(guò)早終止的點(diǎn),，但仍會(huì)在mRNA的端點(diǎn)正常終止。在人體和小鼠細(xì)胞中,，該藥物能恢復(fù)在肌營(yíng)養(yǎng)不良癥中發(fā)生突變的基因的正常轉(zhuǎn)錄,，它在該人類(lèi)疾病的mdx小鼠模型中還能恢復(fù)肌肉功能。
該研究結(jié)果發(fā)表在最新一期的《nature》雜志上。這項(xiàng)工作為也許可用于以無(wú)用突變（nonsense mutations）為作用目標(biāo),、并在各種不同的疾病中恢復(fù)蛋白功能的類(lèi)似藥物提供了希望,。PTC124目前正在進(jìn)行治療肌營(yíng)養(yǎng)不良癥和囊性纖維瘤的臨床試驗(yàn)。
FIGURE 1. PTC124 suppresses premature nonsense codons.
a, b, Cultured HEK293 cells harbouring UAA, UAG or UGA LUC-190 nonsense alleles were treated with increasing concentrations of PTC124 (a) or gentamicin (b) for 16 h, and assayed for luciferase activity. c, d, Synthetic LUC mRNAs, each harbouring different premature termination codons, were incubated with HeLa cell-free extract supplemented with varying concentrations of PTC124 (c) or gentamicin (d), and assayed for luciferase activity after 4 h. Luminescence ratio, drug-treated:control; error bars ( s.d.) are derived from three independent experiments.
原文出處：
Nature Volume 447 Number 7140
PTC124 targets genetic disorders caused by nonsense mutations p87
Ellen M. Welch, Elisabeth R. Barton, Jin Zhuo, Yuki Tomizawa, Westley J. Friesen, Panayiota Trifillis, Sergey Paushkin, Meenal Patel, Christopher R. Trotta, Seongwoo Hwang, Richard G. Wilde, Gary Karp, James Takasugi, Guangming Chen, Stephen Jones, Hongyu Ren, Young-Choon Moon, Donald Corson, Anthony A. Turpoff, Jeffrey A. Campbell, M. Morgan Conn, Atiyya Khan, Neil G. Almstead, Jean Hedrick, Anna Mollin, Nicole Risher, Marla Weetall, Shirley Yeh, Arthur A. Branstrom, Joseph M. Colacino, John Babiak, William D. Ju, Samit Hirawat, Valerie J. Northcutt, Langdon L. Miller, Phyllis Spatrick, Feng He, Masataka Kawana, Huisheng Feng, Allan Jacobson, Stuart W. Peltz & H. Lee Sweeney
doi:10.1038/nature05756
First paragraph | Full Text | PDF (579K) | Supplementary information
See also: Editor's summary | News and Views by Schmitz & Famulok
作者簡(jiǎn)介：
H. LEE SWEENEY, PH.D.
William Maul Measey Professor and Chairman of Physiology
Department of Physiology
Other School of Medicine Affiliations
Pennsylvania Muscle Institute
Department of Medicine (Division of Cardiology)
Cell and Molecular Biology Graduate Program
Degrees
S.B., Massachusetts Institute of Technology, 1975
A.M., Harvard University, 1980
Ph.D., Harvard University, 1984
Honors
William Maul Measey Chair in Physiology
Fellow of the American Heart Association
Professional Affiliations
Biophysical Society
American Heart Association (Basic Research Council)
American Society for Biochemistry & Molecular Biology
Society of General Physiologists
American Society for Cell Biology
Research Interests
Molecular motors; muscle injury and disease; gene transfer into striated muscle; myofibrillogenesis
Research Description
Dr. Sweeney's research program addresses the molecular basis of cellular movement and force generation. His approach encompasses investigations on single molecules, single cells and whole organisms. At the level of the single molecule, the work examines the basic design and function of the molecular motor, myosin. These studies combine protein engineering with biochemical and structural analyses. At the level of isolated cells (cultured myocytes), the research program has two aspects: 1) investigation of the role of various proteins either in the generation of force, or in the transmission of force across the cell membrane, and 2) the process of assembly of the contractile apparatus. Studies at the whole animal level involve gene transfer into muscle (both germline and somatic cell). Somatic cell gene transfer (utilizing viruses) allows the assessment of acute alterations in cell structure and function following viral-driven expression of a single protein. In response to acute changes in properties, feedback pathways intrinsic and extrinsic to the muscle cell signal alterations in the muscle gene expression program that result in an adaptive response. This new approach allows critical evaluation of principles of muscle cell design as well as evaluation of possible causes of and treatments for muscle diseases. Currently, Dr. Sweeney is studying two diseases, Duchenne muscular dystrophy and hypertrophic cardiomyopathy, with this approach.
Representative Publications
Barton-Davis, E.R., Shoturma, D.I., Musaro, A., Rosenthal, N. and Sweeney, H.L. Viral mediated expression of IGF-I blocks the aging-related loss of skeletal muscle function, Proc. Natl. Acad. Sci. USA 95: 15603-15607, 1998.
Barton-Davis, E.R., Cordier, L.L., Shoturma, D.I., Leland, S.E. and Sweeney, H.L. Aminoglycoside antibiotics restore dystrophin function to skeletal muscles of mdx mice, J. Clin. Inves. 104: 375-381, 1999.
Wells, A.L.,, Lin, A.W., Chen, L.-Q., Safer, D., Cain, S.M., Hasson, T., Carragher, B.O., Milligan, R.A., and Sweeney, H.L., Myosin VI is an actin-based motor that moves backwards, Nature 401: 505-508, 1999.
De La Cruz, E.M., Wells, A.L., Safer, D., Ostap, E.M. and Sweeney, H.L. The kinetic mechanism of myosin V. Proc. Natl. Acad. Sci. USA 96: 13726-13731, 1999.
Rock, R.S., Rice, S.E., Wells, A.L., Purcell, T.J., Spudich, J.A. and Sweeney, H.L., Myosin VI is a processive, backwards motorwith a large step size, Proc. Natl. Acad. Sci. USA 98: 13655-13659, 2001.
Coureux, P.D., Wells, A.L., Menetrey, J., Yengo, C.M., Morris, C.A., Sweeney, H.L., Houdusse, A. A structural state of themyosin V motor without bound nucleotide. Nature 425: 419-423, 2003.
Click here for a full list of publications
(searches the National Library of Medicine's PubMed database.)
Stuart W. Peltz Professor
UMDNJ-RWJMS
Dept. Molecular Genetics. Microbiology
and Immunology - Rooms 810/813/823
Post transcriptional control mechanisms
To a first approximation. changes in the expression of specific genes are manifested by changes in the steady-state levels of individual mRNAs. Since the instantaneous concentration of any mRNA is a function of the rate constants for both synthesis and decay. differences in the decay rates of individual mRNAs can have profound effects on the overall levels of expression of specific genes. At a minimum. these effects will reflect the 50-100-fold differences in the decay rates of individual mRNAs within a given eukaryotic cell. However. decay rates can also be regulated. for example as a consequence of autogenous feedback mechanisms. the presence of iron or specific hormones. a particular stage of differentiation or the cell-cycle. heat-shock. or viral infection. Clearly. variations in mRNA decay rates offer the cell considerable flexibility in varying the concentrations of mRNAs and. ultimately. the concentrations of proteins. Altered control of mRNA stability can also lead to aberrant gene regulation and potentially to disease. Further. understanding the mechanisms that control mRNA turnover will lead to improvements in expressing proteins in heterologous systems and in advancing both the ribozyme and antisense RNA technologies for potential therapeutic use.
Our research goals are to understand the mechanisms which a cell utilizes to posttranscriptionally control its mRNA abundance. The following projects will be pursued in my laboratory: 1) The identification of sequence elements that determine mRNA half-lives. This will include defining sequence determinants that either stabilize or destabilize transcripts; 2) The identification and characterization of factors involved in regulating mRNA decay. This will include the identification of nucleases. RNA binding proteins. etc. that are involved in this process. Both biochemical and genetic approaches will be utilized to define these factors; 3) The establishment of an in vitro mRNA turnover system that accurately reflects the decay processes observed in cells. This will allow us to study biochemically these mechanisms; 4) Understanding how the processes of translation and mRNA decay are linked. The sequence elements and trans-acting factors involved in mRNA turnover are apparently intimately linked to the process of protein synthesis. We want to understand how these processes are related using the experimental approaches described above.
Selected Publications
Trotta CR. Paushkin SV. Patel M. Li H. Peltz SW. (2006) Cleavage of pre-tRNAs by the splicing endonuclease requires a composite active site. Nature. 441(7091):375-7.
Wang W. Cajigas IJ. Peltz SW. Wilkinson MF. Gonzalez CI. (2006) Role for Upf2p phosphorylation in Saccharomyces cerevisiae nonsense-mediated mRNA decay. Mol Cell Biol. 26(9):3390-400.
Mehta A. Trotta CR. Peltz SW. (2006) Derepression of the Her-2 uORF is mediated by a novel post-transcriptional control mechanism in cancer cells. Genes Dev. 20(8):939-53.
Micheva-Viteva S. Pacchia AL. Ron Y. Peltz SW. Dougherty JP. (2005) Human immunodeficiency virus type 1 latency model for high-throughput screening. Antimicrob Agents Chemother. 49(12):5185-8.
Vasudevan S. Garneau N. Tu Khounh D. Peltz SW. (2005) p38 mitogen-activated protein kinase/Hog1p regulates translation of the AU-rich-element-bearing MFA2 transcript. Mol Cell Biol. 5(22):9753-63.
Duttagupta R. Tian B. Wilusz CJ. Khounh DT. Soteropoulos P. Ouyang M. Dougherty JP. Peltz SW. (2005) Global analysis of Pub1p targets reveals a coordinate control of gene expression through modulation of binding and stability. Mol Cell Biol. 25(13):5499-513.
Le Roy F. Salehzada T. Bisbal C. Dougherty JP. Peltz SW. (2005) A newly discovered function for RNase L in regulating translation termination. Nat Struct Mol Biol. 12(6):505-12. E
Paushkin SV. Patel M. Furia BS. Peltz SW. Trotta CR. (2004) Identification of a human endonuclease complex reveals a link between tRNA splicing and pre-mRNA 3' end formation. Cell. 117(3):311-21.
Biswas P. Jiang X. Pacchia AL. Dougherty JP. Peltz SW. (2004) The human immunodeficiency virus type 1 ribosomal frameshifting site is an invariant sequence determinant and an important target for antiviral therapy. J Virol. 78(4):2082-7.
Vasudevan S. Peltz SW. Nuclear mRNA surveillance. Curr Opin Cell Biol. (2003) 15(3):332-7.
Duttagupta R. Vasudevan S. Wilusz CJ. Peltz SW. (2003) A yeast homologue of Hsp70. Ssa1p. regulates turnover of the MFA2 transcript through its AU-rich 3' untranslated region. Mol Cell Biol. 23(8):2623-32.
Adelson ME. Pacchia AL. Kaul M. Rando RF. Ron Y. Peltz SW. Dougherty JP. (2003) Toward the development of a virus-cell-based assay for the discovery of novel compounds against human immunodeficiency virus type 1. Antimicrob Agents Chemother. 47(2):501-8.
Vasudevan S. Peltz SW. Wilusz CJ. (2002) Non-stop decay--a new mRNA surveillance pathway. Bioessays. 24:785-8.
Wilusz CJ. Gao M. Jones CL. Wilusz J. Peltz SW (2001). Poly(A) binding proteins regulate both mRNA deadenylation and decapping in yeast cytoplasmic extracts. RNA 7:1416-24.
Vasudevan S. Peltz SW (2001). Regulated ARE-mediated mRNA decay in Saccharomyces cerevisiae. Mol Cell. 7:1191-200.
Ruiz-Echevarria MJ. Munshi R. Tomback J. Kinzy TG. Peltz SW(2001). Characterization of a general stabilizer element that blocks deadenylation-dependent mRNA decay. J Biol Chem. 276:30995-1003.
Wilusz CJ. Wormington M. Peltz SW (2001). The cap-to-tail guide to mRNA turnover. Nat Rev Mol Cell Biol. 2:237-46.
Wang W. Czaplinski K. Rao Y. Peltz SW (2001). The role of Upf proteins in modulating the translation read-through of nonsense-containing transcripts. EMBO J. 20:880-90.
Bhattacharya A. Czaplinski K. Trifillis P. He F. Jacobson A. Peltz SW (2000). Characterization of the biochemical properties of the human Upf1 gene product that is involved in nonsense-mediated mRNA decay. RNA. 6:1226-35.
