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301.
Cajal bodies (CBs) and Gems are nuclear domains that contain factors responsible for spliceosomal small nuclear ribonucleoprotein
(snRNP) biogenesis. The marker protein for CBs is coilin. In addition to snRNPs, coilin and other factors, canonical CBs contain
the survivor of motor neuron protein (SMN). SMN can also localize to Gems. Considering the important role that coilin plays
in the formation and composition of CBs, we tested the splicing efficiency of several cell lines that vary in regards to coilin
level and modification using an artificial reporter substrate. We found that cells with both hypomethylated coilin and Gems
are more efficient at reporter splicing compared to cells in which SMN localizes to CBs. In contrast, coilin reduction, which
induces Gem formation, decreases cell proliferation and artificial reporter splicing. These findings demonstrate that coilin
modifications or levels impact artificial reporter splicing, possibly by influencing snRNP biogenesis.
Received 26 December 2007; received after revision 5 February 2008; accepted 7 February 2008 相似文献
302.
Richards JB Yuan X Geller F Waterworth D Bataille V Glass D Song K Waeber G Vollenweider P Aben KK Kiemeney LA Walters B Soranzo N Thorsteinsdottir U Kong A Rafnar T Deloukas P Sulem P Stefansson H Stefansson K Spector TD Mooser V 《Nature genetics》2008,40(11):1282-1284
We conducted a genome-wide association study for androgenic alopecia in 1,125 men and identified a newly associated locus at chromosome 20p11.22, confirmed in three independent cohorts (n = 1,650; OR = 1.60, P = 1.1 x 10(-14) for rs1160312). The one man in seven who harbors risk alleles at both 20p11.22 and AR (encoding the androgen receptor) has a sevenfold-increased odds of androgenic alopecia (OR = 7.12, P = 3.7 x 10(-15)). 相似文献
303.
Scott RH Douglas J Baskcomb L Huxter N Barker K Hanks S Craft A Gerrard M Kohler JA Levitt GA Picton S Pizer B Ronghe MD Williams D;Factors Associated with Childhood Tumours 《Nature genetics》2008,40(11):1329-1334
Constitutional abnormalities at the imprinted 11p15 growth regulatory region cause syndromes characterized by disordered growth, some of which include a risk of Wilms tumor. We explored their possible contribution to nonsyndromic Wilms tumor and identified constitutional 11p15 abnormalities in genomic lymphocyte DNA from 13 of 437 individuals (3%) with sporadic Wilms tumor without features of growth disorders, including 12% of bilateral cases (P = 0.001) and in one familial Wilms tumor pedigree. No abnormality was detected in 220 controls (P = 0.006). Abnormalities identified included H19 DMR epimutations, uniparental disomy 11p15 and H19 DMR imprinting center mutations (one microinsertion and one microdeletion), thus identifying microinsertion as a new class of imprinting center mutation. Our data identify constitutional 11p15 defects as one of the most common known causes of Wilms tumor, provide mechanistic insights into imprinting disruption and reveal clinically important epigenotype-phenotype associations. The impact on clinical management dictates that constitutional 11p15 analysis should be considered in all individuals with Wilms tumor. 相似文献
304.
Kao WH Klag MJ Meoni LA Reich D Berthier-Schaad Y Li M Coresh J Patterson N Tandon A Powe NR Fink NE Sadler JH Weir MR Abboud HE Adler SG Divers J Iyengar SK Freedman BI Kimmel PL Knowler WC Kohn OF Kramp K Leehey DJ Nicholas SB Pahl MV Schelling JR Sedor JR Thornley-Brown D Winkler CA Smith MW Parekh RS;Family Investigation of Nephropathy Diabetes Research Group 《Nature genetics》2008,40(10):1185-1192
As end-stage renal disease (ESRD) has a four times higher incidence in African Americans compared to European Americans, we hypothesized that susceptibility alleles for ESRD have a higher frequency in the West African than the European gene pool. We carried out a genome-wide admixture scan in 1,372 ESRD cases and 806 controls and found a highly significant association between excess African ancestry and nondiabetic ESRD (lod score = 5.70) but not diabetic ESRD (lod = 0.47) on chromosome 22q12. Each copy of the European ancestral allele conferred a relative risk of 0.50 (95% CI = 0.39-0.63) compared to African ancestry. Multiple common SNPs (allele frequencies ranging from 0.2 to 0.6) in the gene encoding nonmuscle myosin heavy chain type II isoform A (MYH9) were associated with two to four times greater risk of nondiabetic ESRD and accounted for a large proportion of the excess risk of ESRD observed in African compared to European Americans. 相似文献
305.
Stacey SN Gudbjartsson DF Sulem P Bergthorsson JT Kumar R Thorleifsson G Sigurdsson A Jakobsdottir M Sigurgeirsson B Benediktsdottir KR Thorisdottir K Ragnarsson R Scherer D Rudnai P Gurzau E Koppova K Höiom V Botella-Estrada R Soriano V Juberías P Grasa M Carapeto FJ Tabuenca P Gilaberte Y Gudmundsson J Thorlacius S Helgason A Thorlacius T Jonasdottir A Blondal T Gudjonsson SA Jonsson GF Saemundsdottir J Kristjansson K Bjornsdottir G Sveinsdottir SG Mouy M Geller F Nagore E Mayordomo JI 《Nature genetics》2008,40(11):1313-1318
To search for new sequence variants that confer risk of cutaneous basal cell carcinoma (BCC), we conducted a genome-wide SNP association study of 930 Icelanders with BCC and 33,117 controls. After analyzing 304,083 SNPs, we observed signals from loci at 1p36 and 1q42, and replicated these associations in additional sample sets from Iceland and Eastern Europe. Overall, the most significant signals were from rs7538876 on 1p36 (OR = 1.28, P = 4.4 x 10(-12)) and rs801114 on 1q42 (OR = 1.28, P = 5.9 x 10(-12)). The 1p36 locus contains the candidate genes PADI4, PADI6, RCC2 and ARHGEF10L, and the gene nearest to the 1q42 locus is the ras-homolog RHOU. Neither locus was associated with fair pigmentation traits that are known risk factors for BCC, and no risk was observed for melanoma. Approximately 1.6% of individuals of European ancestry are homozygous for both variants, and their estimated risk of BCC is 2.68 times that of noncarriers. 相似文献
306.
Zinc binding to peptide analogs of the structural zinc site in alcohol dehydrogenase: Implications for an entatic state 总被引:1,自引:0,他引:1
Bergman T Zhang K Palmberg C Jörnvall H Auld DS 《Cellular and molecular life sciences : CMLS》2008,65(24):4019-4027
Zinc binding to the peptide replica and analogs to residues 93–115 of horse liver alcohol dehydrogenase (ADH) was examined
by competition of the peptides and the chromophoric chelator 4-(2- pyridylazo)resorcinol for zinc and X-ray absorption fine
structure analysis of the zinc ligands. In the enzyme, zinc is coordinated by four Cys residues. In the peptide replica, zinc
is bound to three Cys and one His residue. A four-Cys zinc coordination is observed only when His is removed, leading to increased
zinc stability. ADH crystal structures reveal that the ε-amino group of the conserved residue Lys323 is within H-bond distance
of the backbone amide oxygens of residues 103, 105 and 108, likely stabilizing the zinc coordination in the enzyme. The peptide
data thus indicate structural strain and increased energy in the zinc-binding site in the protein, characteristic of an entatic
state, implying a functional nature for this zinc site.
Received 3 July 2008; received after revision 11 August 2008; accepted 1 September 2008 相似文献
307.
Cardiolipin, the heart of mitochondrial metabolism 总被引:5,自引:0,他引:5
Cardiolipin is a unique phospholipid, which is almost exclusively localized in the mitochondrial inner membrane where it is
synthesized from phosphatidylglycerol and cytidinediphosphate-diacylglycerol. After primary synthesis, the mature acyl chain
composition of cardiolipin is achieved by at least two remodeling mechanisms. In the mitochondrial membrane cardiolipin plays
an important role in energy metabolism, mainly by providing stability for the individual enzymes and enzyme complexes involved
in energy production. Moreover, cardiolipin is involved in different stages of the mitochondrial apoptotic process and in
mitochondrial membrane dynamics. Cardiolipin alterations have been described in various pathological conditions. Patients
suffering from Barth syndrome have an altered cardiolipin homeostasis caused by a primary deficiency in cardiolipin remodeling.
Alterations in cardiolipin content or composition have also been reported in more frequent diseases such as diabetes and heart
failure. In this review we provide an overview of cardiolipin metabolism, function and its role in different pathological
states.
Received 16 January 2008; received after revision 26 February 2008; accepted 26 March 2008 相似文献
308.
Uppal S Diggle CP Carr IM Fishwick CW Ahmed M Ibrahim GH Helliwell PS Latos-Bieleńska A Phillips SE Markham AF Bennett CP Bonthron DT 《Nature genetics》2008,40(6):789-793
Digital clubbing, recognized by Hippocrates in the fifth century BC, is the outward hallmark of pulmonary hypertrophic osteoarthropathy, a clinical constellation that develops secondary to various acquired diseases, especially intrathoracic neoplasm. The pathogenesis of clubbing and hypertrophic osteoarthropathy has hitherto been poorly understood, but a clinically indistinguishable primary (idiopathic) form of hypertrophic osteoarthropathy (PHO) is recognized. This familial disorder can cause diagnostic confusion, as well as significant disability. By autozygosity methods, we mapped PHO to chromosome 4q33-q34 and identified mutations in HPGD, encoding 15-hydroxyprostaglandin dehydrogenase, the main enzyme of prostaglandin degradation. Homozygous individuals develop PHO secondary to chronically elevated prostaglandin E(2) levels. Heterozygous relatives also show milder biochemical and clinical manifestations. These findings not only suggest therapies for PHO, but also imply that clubbing secondary to other pathologies may be prostaglandin mediated. Testing for HPGD mutations and biochemical testing for HPGD deficiency in patients with unexplained clubbing might help to obviate extensive searches for occult pathology. 相似文献
309.
310.