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271.
Liu ZM Chen GG Vlantis AC Tse GM Shum CK van Hasselt CA 《Cellular and molecular life sciences : CMLS》2007,64(11):1428-1436
The molecular mechanism responsible for cadmium-induced cell death in thyroid cancer cells (FRO) is unknown. We demonstrated
that apoptosis of FRO cells induced by cadmium was concentration and time dependent. Cadmium caused the rapid elevation of
intracellular calcium and induced phosphorylation of Akt, p53, JNK, ERK and p38. Inhibition of PI3K/Akt attenuated the cadmium-induced
apoptosis, but the inhibition of JNK inhibitor, ERK or p38 aggravated it, indicating that activation of PI3K/Akt was a pro-apoptosis
signal in response to cadmium treatment, whereas the activation of stress-activated protein kinase JNK, ERK and p38 functioned
as survival signals to counteract the cadmium-induced apoptosis. Buffering of the calcium response attenuated mitochondrial
impairment, recovered the cadmium-activated Akt, p53, JNK, ERK and p38, and subsequently blocked the apoptosis. These results
suggested that apoptosis induced by cadmium in FRO cells was initiated by the rapid elevation of intracellular calcium, followed
by calcium-mediated activation of PI3K/Akt and mitochondrial impairment.
Received 28 February 2007; received after revision 2 April 2007; accepted 23 April 2007 相似文献
272.
Vanin AF Bevers LM Slama-Schwok A van Faassen EE 《Cellular and molecular life sciences : CMLS》2007,64(1):96-103
Cultured bEND.3 endothelial cells show a marked increase in NO production when subjected to anoxia, even though the normal
arginine pathway of NO formation is blocked due to absence of oxygen. The rate of anoxic NO production exceeds basal unstimulated
NO synthesis in normoxic cells. The anoxic release of NO is mediated by endothelial nitric oxide synthase (eNOS), can be abolished
by inhibitors of NOS and is accompanied by consumption of intracellular nitrite. The anoxic NO release is unaffected by the
xanthine oxidase inhibitor oxypurinol. The phenomenon is attributed to anoxic reduction of intracellular nitrite by eNOS,
and its magnitude and duration suggests that the nitrite reductase activity of eNOS is relevant for fast NO delivery in hypoxic
vascular tissues.
Received 20 August 2006; received after revision 21 September 2006; accepted 8 November 2006 相似文献
273.
Reverse breeding in Arabidopsis thaliana generates homozygous parental lines from a heterozygous plant 总被引:1,自引:0,他引:1
Wijnker E van Dun K de Snoo CB Lelivelt CL Keurentjes JJ Naharudin NS Ravi M Chan SW de Jong H Dirks R 《Nature genetics》2012,44(4):467-470
Traditionally, hybrid seeds are produced by crossing selected inbred lines. Here we provide a proof of concept for reverse breeding, a new approach that simplifies meiosis such that homozygous parental lines can be generated from a vigorous hybrid individual. We silenced DMC1, which encodes the meiotic recombination protein DISRUPTED MEIOTIC cDNA1, in hybrids of A. thaliana, so that non-recombined parental chromosomes segregate during meiosis. We then converted the resulting gametes into adult haploid plants, and subsequently into homozygous diploids, so that each contained half the genome of the original hybrid. From 36 homozygous lines, we selected 3 (out of 6) complementing parental pairs that allowed us to recreate the original hybrid by intercrossing. In addition, this approach resulted in a complete set of chromosome-substitution lines. Our method allows the selection of a single choice offspring from a segregating population and preservation of its heterozygous genotype by generating homozygous founder lines. 相似文献
274.
Thye T Owusu-Dabo E Vannberg FO van Crevel R Curtis J Sahiratmadja E Balabanova Y Ehmen C Muntau B Ruge G Sievertsen J Gyapong J Nikolayevskyy V Hill PC Sirugo G Drobniewski F van de Vosse E Newport M Alisjahbana B Nejentsev S Ottenhoff TH Hill AV Horstmann RD Meyer CG 《Nature genetics》2012,44(3):257-259
After imputation of data from the 1000 Genomes Project into a genome-wide dataset of Ghanaian individuals with tuberculosis and controls, we identified a resistance locus on chromosome 11p13 downstream of the WT1 gene (encoding Wilms tumor 1). The strongest signal was obtained at the rs2057178 SNP (P = 2.63 × 10(-9)). Replication in Gambian, Indonesian and Russian tuberculosis case-control study cohorts increased the significance level for the association with this SNP to P = 2.57 × 10(-11). 相似文献
275.
Manning AK Hivert MF Scott RA Grimsby JL Bouatia-Naji N Chen H Rybin D Liu CT Bielak LF Prokopenko I Amin N Barnes D Cadby G Hottenga JJ Ingelsson E Jackson AU Johnson T Kanoni S Ladenvall C Lagou V Lahti J Lecoeur C Liu Y Martinez-Larrad MT Montasser ME Navarro P Perry JR Rasmussen-Torvik LJ Salo P Sattar N Shungin D Strawbridge RJ Tanaka T van Duijn CM An P de Andrade M Andrews JS Aspelund T Atalay M Aulchenko Y Balkau B Bandinelli S Beckmann JS Beilby JP Bellis C Bergman RN Blangero J 《Nature genetics》2012,44(6):659-669
Recent genome-wide association studies have described many loci implicated in type 2 diabetes (T2D) pathophysiology and β-cell dysfunction but have contributed little to the understanding of the genetic basis of insulin resistance. We hypothesized that genes implicated in insulin resistance pathways might be uncovered by accounting for differences in body mass index (BMI) and potential interactions between BMI and genetic variants. We applied a joint meta-analysis approach to test associations with fasting insulin and glucose on a genome-wide scale. We present six previously unknown loci associated with fasting insulin at P < 5 × 10(-8) in combined discovery and follow-up analyses of 52 studies comprising up to 96,496 non-diabetic individuals. Risk variants were associated with higher triglyceride and lower high-density lipoprotein (HDL) cholesterol levels, suggesting a role for these loci in insulin resistance pathways. The discovery of these loci will aid further characterization of the role of insulin resistance in T2D pathophysiology. 相似文献
276.
Stolk L Perry JR Chasman DI He C Mangino M Sulem P Barbalic M Broer L Byrne EM Ernst F Esko T Franceschini N Gudbjartsson DF Hottenga JJ Kraft P McArdle PF Porcu E Shin SY Smith AV van Wingerden S Zhai G Zhuang WV Albrecht E Alizadeh BZ Aspelund T Bandinelli S Lauc LB Beckmann JS Boban M Boerwinkle E Broekmans FJ Burri A Campbell H Chanock SJ Chen C Cornelis MC Corre T Coviello AD d'Adamo P Davies G de Faire U de Geus EJ Deary IJ Dedoussis GV Deloukas P Ebrahim S Eiriksdottir G Emilsson V 《Nature genetics》2012,44(3):260-268
To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural menopause (at P < 5 × 10(-8)). Candidate genes located at these newly associated loci include genes implicated in DNA repair (EXO1, HELQ, UIMC1, FAM175A, FANCI, TLK1, POLG and PRIM1) and immune function (IL11, NLRP11 and PRRC2A (also known as BAT2)). Gene-set enrichment pathway analyses using the full GWAS data set identified exoDNase, NF-κB signaling and mitochondrial dysfunction as biological processes related to timing of menopause. 相似文献
277.
Hunt KA Smyth DJ Balschun T Ban M Mistry V Ahmad T Anand V Barrett JC Bhaw-Rosun L Bockett NA Brand OJ Brouwer E Concannon P Cooper JD Dias KR van Diemen CC Dubois PC Edkins S Fölster-Holst R Fransen K Glass DN Heap GA Hofmann S Huizinga TW Hunt S Langford C Lee J Mansfield J Marrosu MG Mathew CG Mein CA Müller-Quernheim J Nutland S Onengut-Gumuscu S Ouwehand W Pearce K Prescott NJ Posthumus MD Potter S Rosati G Sambrook J Satsangi J Schreiber S Shtir C Simmonds MJ Sudman M Thompson SD Toes R 《Nature genetics》2012,44(1):3-5
278.
Pansuriya TC van Eijk R d'Adamo P van Ruler MA Kuijjer ML Oosting J Cleton-Jansen AM van Oosterwijk JG Verbeke SL Meijer D van Wezel T Nord KH Sangiorgi L Toker B Liegl-Atzwanger B San-Julian M Sciot R Limaye N Kindblom LG Daugaard S Godfraind C Boon LM Vikkula M Kurek KC Szuhai K French PJ Bovée JV 《Nature genetics》2011,43(12):1256-1261
Ollier disease and Maffucci syndrome are non-hereditary skeletal disorders characterized by multiple enchondromas (Ollier disease) combined with spindle cell hemangiomas (Maffucci syndrome). We report somatic heterozygous mutations in IDH1 (c.394C>T encoding an R132C substitution and c.395G>A encoding an R132H substitution) or IDH2 (c.516G>C encoding R172S) in 87% of enchondromas (benign cartilage tumors) and in 70% of spindle cell hemangiomas (benign vascular lesions). In total, 35 of 43 (81%) subjects with Ollier disease and 10 of 13 (77%) with Maffucci syndrome carried IDH1 (98%) or IDH2 (2%) mutations in their tumors. Fourteen of 16 subjects had identical mutations in separate lesions. Immunohistochemistry to detect mutant IDH1 R132H protein suggested intraneoplastic and somatic mosaicism. IDH1 mutations in cartilage tumors were associated with hypermethylation and downregulated expression of several genes. Mutations were also found in 40% of solitary central cartilaginous tumors and in four chondrosarcoma cell lines, which will enable functional studies to assess the role of IDH1 and IDH2 mutations in tumor formation. 相似文献
279.
Höglinger GU Melhem NM Dickson DW Sleiman PM Wang LS Klei L Rademakers R de Silva R Litvan I Riley DE van Swieten JC Heutink P Wszolek ZK Uitti RJ Vandrovcova J Hurtig HI Gross RG Maetzler W Goldwurm S Tolosa E Borroni B Pastor P;PSP Genetics Study Group Cantwell LB Han MR Dillman A van der Brug MP Gibbs JR Cookson MR Hernandez DG Singleton AB Farrer MJ Yu CE Golbe LI Revesz T Hardy J Lees AJ Devlin B Hakonarson H Müller U Schellenberg GD 《Nature genetics》2011,43(7):699-705
Progressive supranuclear palsy (PSP) is a movement disorder with prominent tau neuropathology. Brain diseases with abnormal tau deposits are called tauopathies, the most common of which is Alzheimer's disease. Environmental causes of tauopathies include repetitive head trauma associated with some sports. To identify common genetic variation contributing to risk for tauopathies, we carried out a genome-wide association study of 1,114 individuals with PSP (cases) and 3,247 controls (stage 1) followed by a second stage in which we genotyped 1,051 cases and 3,560 controls for the stage 1 SNPs that yielded P ≤ 10(-3). We found significant previously unidentified signals (P < 5 × 10(-8)) associated with PSP risk at STX6, EIF2AK3 and MOBP. We confirmed two independent variants in MAPT affecting risk for PSP, one of which influences MAPT brain expression. The genes implicated encode proteins for vesicle-membrane fusion at the Golgi-endosomal interface, for the endoplasmic reticulum unfolded protein response and for a myelin structural component. 相似文献
280.
Hoischen A van Bon BW Rodríguez-Santiago B Gilissen C Vissers LE de Vries P Janssen I van Lier B Hastings R Smithson SF Newbury-Ecob R Kjaergaard S Goodship J McGowan R Bartholdi D Rauch A Peippo M Cobben JM Wieczorek D Gillessen-Kaesbach G Veltman JA Brunner HG de Vries BB 《Nature genetics》2011,43(8):729-731
Bohring-Opitz syndrome is characterized by severe intellectual disability, distinctive facial features and multiple congenital malformations. We sequenced the exomes of three individuals with Bohring-Opitz syndrome and in each identified heterozygous de novo nonsense mutations in ASXL1, which is required for maintenance of both activation and silencing of Hox genes. In total, 7 out of 13 subjects with a Bohring-Opitz phenotype had de novo ASXL1 mutations, suggesting that the syndrome is genetically heterogeneous. 相似文献