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261.
Sayer JA Otto EA O'Toole JF Nurnberg G Kennedy MA Becker C Hennies HC Helou J Attanasio M Fausett BV Utsch B Khanna H Liu Y Drummond I Kawakami I Kusakabe T Tsuda M Ma L Lee H Larson RG Allen SJ Wilkinson CJ Nigg EA Shou C Lillo C Williams DS Hoppe B Kemper MJ Neuhaus T Parisi MA Glass IA Petry M Kispert A Gloy J Ganner A Walz G Zhu X Goldman D Nurnberg P Swaroop A Leroux MR Hildebrandt F 《Nature genetics》2006,38(6):674-681
262.
Truncating mutations in the Fanconi anemia J gene BRIP1 are low-penetrance breast cancer susceptibility alleles 总被引:21,自引:0,他引:21
Seal S Thompson D Renwick A Elliott A Kelly P Barfoot R Chagtai T Jayatilake H Ahmed M Spanova K North B McGuffog L Evans DG Eccles D;Breast Cancer Susceptibility Collaboration 《Nature genetics》2006,38(11):1239-1241
We identified constitutional truncating mutations of the BRCA1-interacting helicase BRIP1 in 9/1,212 individuals with breast cancer from BRCA1/BRCA2 mutation-negative families but in only 2/2,081 controls (P = 0.0030), and we estimate that BRIP1 mutations confer a relative risk of breast cancer of 2.0 (95% confidence interval = 1.2-3.2, P = 0.012). Biallelic BRIP1 mutations were recently shown to cause Fanconi anemia complementation group J. Thus, inactivating truncating mutations of BRIP1, similar to those in BRCA2, cause Fanconi anemia in biallelic carriers and confer susceptibility to breast cancer in monoallelic carriers. 相似文献
263.
Huntington’s disease: from huntingtin function and dysfunction to therapeutic strategies 总被引:3,自引:0,他引:3
Borrell-Pagès M Zala D Humbert S Saudou F 《Cellular and molecular life sciences : CMLS》2006,63(22):2642-2660
Huntington’s disease (HD) is a neurodegenerative disorder that usually starts in middle age and is characterized by involuntary
movements (chorea), personality changes and dementia, leading to death within 10–20 years. The defective gene in HD contains
a trinucleotide CAG repeat expansion within its coding region that expresses a polyglutamine repeat in the protein huntingtin.
Together with the characteristic formation of aggregates in HD, aberrant protein interactions and several post-translational
modifications affect huntingtin during disease progression and lead to the dysfunction and death of selective neurons in the
brains of patients. The exact molecular mechanisms by which mutant huntingtin induces cell death are not completely understood
but may involve the gain of new toxic functions and the loss of the beneficial properties of huntingtin. This review focuses
on the cellular functions in which huntingtin is involved and how a better understanding of pathogenic pathways can lead to
new therapeutic approaches.
Received 24 May 2006; received after revision 5 July 2006; accepted 23 August 2006 相似文献
264.
Lehmann F Tiralongo E Tiralongo J 《Cellular and molecular life sciences : CMLS》2006,63(12):1331-1354
Sialic acids consist of a family of acidic ninecarbon sugars that are typically located at the terminal positions of a variety
of glycoconjugates. Naturally occurring sialic acids show an immense diversity of structure, and this reflects their involvement
in a variety of biologically important processes. One such process involves the direct participation of sialic acids in recognition
events through specific interactions with lectins, a family of proteins that recognise and bind sugars. This review will present
a detailed overview of our current knowledge regarding the occurrence, specificity and function of sialic acid-specific lectins,
particularly those that occur in viruses, bacteria and non-vertebrate eukaryotes.
Received 13 December 2005; received after revision 9 February 2006; accepted 15 February 2006 相似文献
265.
5-Methylcytosine localised in mammalian constitutive heterochromatin 总被引:26,自引:0,他引:26
266.
Ethanol, 3 g/kg i.p., did not significantly alter the acute toxicity of amphetamine in the mouse. However, the urinary metabolite pattern was changed, suggesting that ethanol suppressed metabolism of the stimulant during the initial 6 h period. After 24 h, the mouse metabolized the same fraction of a given dose of amphetamine, whether it was given as amphetamine alone or amphetamine mixed with 2,3 or 4 g/kg ethanol. 相似文献
267.
桥梁结构在各种荷载作用下产生的内力和弯矩影响着桥梁的性能.桥梁弯曲、扭转和挠度等过大时会导致结构的破坏,这在结构设计阶段就应加以分析.本文提出一种有限条简化分析方法,可以较好地分析桥梁的挠度、弯曲和扭转变形.通过对一座简支板梁桥模型的分析,与现行有限元方法的分析结果进行了比较.结果表明,本方法能够较好地处理边界条件,只需要很少的输入工作就可以得到正确的分析结果,从而为结构工程师提供了一种用于分析板梁桥在交通荷载作用下行为的有效工具. 相似文献
268.
269.
Gene polymorphism in Netherton and common atopic disease. 总被引:13,自引:0,他引:13
A J Walley S Chavanas M F Moffatt R M Esnouf B Ubhi R Lawrence K Wong G R Abecasis E Y Jones J I Harper A Hovnanian W O Cookson 《Nature genetics》2001,29(2):175-178
Atopic dermatitis (AD) and asthma are characterized by IgE-mediated atopic (allergic) responses to common proteins (allergens), many of which are proteinases. Loci influencing atopy have been localized to a number of chromosomal regions, including the chromosome 5q31 cytokine cluster. Netherton disease is a rare recessive skin disorder in which atopy is a universal accompaniment. The gene underlying Netherton disease (SPINK5) encodes a 15-domain serine proteinase inhibitor (LEKTI) which is expressed in epithelial and mucosal surfaces and in the thymus. We have identified six coding polymorphisms in SPINK5 (Table 1) and found that a Glu420-->Lys variant shows significant association with atopy and AD in two independent panels of families. Our results implicate a previously unrecognized pathway for the development of common allergic illnesses. 相似文献
270.
The chromosomes of eukaryotic cells are separated from the cytoplasm by the nuclear envelope. The nuclear envelope includes two riveted membranes, plus embedded pore complexes that mediate nuclear import and export. In this sense, the nuclear envelope is truly a border zone. However, the envelope also links directly to chromosomes, and anchors two major infrastructures--the nuclear lamina and Tpr filaments--to the nuclear perimeter. Proteins of the nuclear envelope mediate a variety of fundamental activities, including DNA replication, gene expression and silencing, chromatin organization, cell division, apoptosis, sperm nuclear remodeling, the behavior of pronuclei, cell fate determination, nuclear migration and cell polarity. Furthermore, mutations in nuclear lamins and lamin-binding proteins cause tissue-specific inherited diseases. This special issue of Cell and Molecular Life Sciences is devoted to recent major advances in the characterization of nuclear envelope proteins and their roles. We offer here an overview of the topics covered in this issue of CMLS, and also discuss the emerging recognition that the nuclear envelope is an organelle critical for a wide range of genetic and developmental activity in multicellular organisms. 相似文献