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41.
Gissen P Johnson CA Morgan NV Stapelbroek JM Forshew T Cooper WN McKiernan PJ Klomp LW Morris AA Wraith JE McClean P Lynch SA Thompson RJ Lo B Quarrell OW Di Rocco M Trembath RC Mandel H Wali S Karet FE Knisely AS Houwen RH Kelly DA Maher ER 《Nature genetics》2004,36(4):400-404
ARC syndrome (OMIM 208085) is an autosomal recessive multisystem disorder characterized by neurogenic arthrogryposis multiplex congenita, renal tubular dysfunction and neonatal cholestasis with bile duct hypoplasia and low gamma glutamyl transpeptidase (gGT) activity. Platelet dysfunction is common. Affected infants do not thrive and usually die in the first year of life. To elucidate the molecular basis of ARC, we mapped the disease to a 7-cM interval on 15q26.1 and then identified germline mutations in the gene VPS33B in 14 kindreds with ARC. VPS33B encodes a homolog of the class C yeast vacuolar protein sorting gene, Vps33, that contains a Sec1-like domain important in the regulation of vesicle-to-target SNARE complex formation and subsequent membrane fusion. 相似文献
42.
Oncogenic protein tyrosine kinases 总被引:6,自引:0,他引:6
Pulford K Lamant L Espinos E Jiang Q Xue L Turturro F Delsol G Morris SW 《Cellular and molecular life sciences : CMLS》2004,61(23):2939-2953
Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase, the normal role of which remains to be completely elucidated. Although work carried out in mammals suggests a function in neural development, results from studies in Drosophila indicate an additional role in visceral muscle differentiation. The aberrant expression of full-length ALK receptor proteins has been reported in neuroblastomas and glioblastomas, while the occurrence of ALK fusion proteins in anaplastic large cell lymphoma (ALCL) has resulted in the identification of the new tumor entity, ALK-positive ALCL. ALK represents one of few examples of a receptor tyrosine kinase implicated in oncogenesis in both haematopoietic and non-haematopoietic tumors, given that ALK fusions also occur in the mesenchymal tumor known as inflammatory myofibroblastic tumor (IMT). The study of ALK fusion proteins, besides demonstrating their importance in tumor development, has also raised the possibility of new therapeutic treatments for patients with ALK-positive malignancies. 相似文献
43.
Yalcin B Willis-Owen SA Fullerton J Meesaq A Deacon RM Rawlins JN Copley RR Morris AP Flint J Mott R 《Nature genetics》2004,36(11):1197-1202
Here we present a strategy to determine the genetic basis of variance in complex phenotypes that arise from natural, as opposed to induced, genetic variation in mice. We show that a commercially available strain of outbred mice, MF1, can be treated as an ultrafine mosaic of standard inbred strains and accordingly used to dissect a known quantitative trait locus influencing anxiety. We also show that this locus can be subdivided into three regions, one of which contains Rgs2, which encodes a regulator of G protein signaling. We then use quantitative complementation to show that Rgs2 is a quantitative trait gene. This combined genetic and functional approach should be applicable to the analysis of any quantitative trait. 相似文献
44.
The herbivorous insects of tropical forests constitute some of the most diverse communities of living organisms. For this reason it has been difficult to discover the degree to which these communities are structured, and by what processes. Interspecific competition for resources does occur, but its contemporary importance is limited because most pairs of potentially competing insects feed on different host plants. An alternative way in which species can interact is through shared natural enemies, a process called apparent competition. Despite extensive theoretical discussion there are few field demonstrations of apparent competition, and none in hyper-diverse tropical communities. Here, we experimentally removed two species of herbivore from a community of leaf-mining insects in a tropical forest. We predicted that other species that share natural enemies with the two removed species would experience lower parasitism and have higher population densities in treatment compared with control sites. In both cases (on removal of a dipteran and a coleopteran leaf-miner species) we found significantly lower parasitism, and in one case (removal of the dipteran) we found significantly higher abundance a year after the manipulation. Our results suggest that apparent competition may be important in structuring tropical insect communities. 相似文献
45.
Ionic liquids and eutectic mixtures as solvent and template in synthesis of zeolite analogues 总被引:3,自引:0,他引:3
The challenges associated with synthesizing porous materials mean that new classes of zeolites (zeotypes)-such as aluminosilicate zeolites and zeolite analogues-together with new methods of preparing known zeotypes, continue to be of great importance. Normally these materials are prepared hydrothermally with water as the solvent in a sealed autoclave under autogenous pressure. The reaction mixture usually includes an organic template or 'structure-directing agent' that guides the synthesis pathway towards particular structures. Here we report the preparation of aluminophosphate zeolite analogues by using ionic liquids and eutectic mixtures. An imidazolium-based ionic liquid acts as both solvent and template, leading to four zeotype frameworks under different experimental conditions. The structural characteristics of the materials can be traced back to the solvent chemistry used. Because of the vanishingly low vapour pressure of ionic liquids, synthesis takes place at ambient pressure, eliminating safety concerns associated with high hydrothermal pressures. The ionic liquid can also be recycled for further use. A choline chloride/urea eutectic mixture is also used in the preparation of a new zeotype framework. 相似文献
46.
Weedon MN Lettre G Freathy RM Lindgren CM Voight BF Perry JR Elliott KS Hackett R Guiducci C Shields B Zeggini E Lango H Lyssenko V Timpson NJ Burtt NP Rayner NW Saxena R Ardlie K Tobias JH Ness AR Ring SM Palmer CN Morris AD Peltonen L Salomaa V;Diabetes Genetics Initiative;Wellcome Trust Case Control Consortium Davey Smith G Groop LC Hattersley AT McCarthy MI Hirschhorn JN Frayling TM 《Nature genetics》2007,39(10):1245-1250
Human height is a classic, highly heritable quantitative trait. To begin to identify genetic variants influencing height, we examined genome-wide association data from 4,921 individuals. Common variants in the HMGA2 oncogene, exemplified by rs1042725, were associated with height (P = 4 x 10(-8)). HMGA2 is also a strong biological candidate for height, as rare, severe mutations in this gene alter body size in mice and humans, so we tested rs1042725 in additional samples. We confirmed the association in 19,064 adults from four further studies (P = 3 x 10(-11), overall P = 4 x 10(-16), including the genome-wide association data). We also observed the association in children (P = 1 x 10(-6), N = 6,827) and a tall/short case-control study (P = 4 x 10(-6), N = 3,207). We estimate that rs1042725 explains approximately 0.3% of population variation in height (approximately 0.4 cm increased adult height per C allele). There are few examples of common genetic variants reproducibly associated with human quantitativetraits; these results represent, to our knowledge, the first consistently replicated association with adult and childhood height. 相似文献
47.
R. Yarom G. E. Morris R. Froede J. Schaper 《Cellular and molecular life sciences : CMLS》1992,48(6):614-616
Using monoclonal antibodies against two different regions of the helical rod part of dystrophin1, we have localized dystrophin on both plasma membrane and transverse tubules in cardiac muscle of man and several animal species. The staining persisted after experimental ischaemia, and was observed in long-standing heart disease. No immunostaining was seen at the intercalated discs. In skeletal muscle the same two antibodies stained only the plasma membrane. 相似文献
48.
C T Jones S Morris C M Yates A Moffoot C Sharpe D J Brock D St Clair 《Nature genetics》1992,1(4):306-309
Following reports of mutations of codon 717 in exon 17 of the amyloid precursor protein (APP) gene in early-onset familial Alzheimer's disease, we screened exon 17 for new mutations in presenile dementia. The majority of the 105 patients screened had definite or probable Alzheimer's disease, but we also included atypical cases and some chronic schizophrenics. We identified a single abnormal case--a chronic schizophrenic with cognitive defects. Sequencing revealed a C to T nucleotide substitution which produces an alanine to valine change at codon 713. We were unable to detect the mutation in the remaining members of the original cohort nor in a further 100 chronic schizophrenics and 100 non-demented controls. Nonetheless, the position of the mutation in a critical portion of the APP gene suggests that it may well prove to be pathogenic. 相似文献
49.
J. E. Morris 《Cellular and molecular life sciences : CMLS》1962,18(12):567-568
Zusammenfassung Im Ei der AscidieHerdmania momus hebt sich nach der Besamung die Befruchtungsmembran von der äusseren Haut ab. Die Korrelationen, die bestehen zwischen Membranabhebung und Befruchtung, sowie ihrem Unterbleiben und der Sterilität, stützen wiederum die Chorionblocktheorie der Autosterilität. 相似文献
50.
Fairhurst RM Baruch DI Brittain NJ Ostera GR Wallach JS Hoang HL Hayton K Guindo A Makobongo MO Schwartz OM Tounkara A Doumbo OK Diallo DA Fujioka H Ho M Wellems TE 《Nature》2005,435(7045):1117-1121
Haemoglobin C, which carries a glutamate-to-lysine mutation in the beta-globin chain, protects West African children against Plasmodium falciparum malaria. Mechanisms of protection are not established for the heterozygous (haemoglobin AC) or homozygous (haemoglobin CC) states. Here we report a marked effect of haemoglobin C on the cell-surface properties of P. falciparum-infected erythrocytes involved in pathogenesis. Relative to parasite-infected normal erythrocytes (haemoglobin AA), parasitized AC and CC erythrocytes show reduced adhesion to endothelial monolayers expressing CD36 and intercellular adhesion molecule-1 (ICAM-1). They also show impaired rosetting interactions with non-parasitized erythrocytes, and reduced agglutination in the presence of pooled sera from malaria-immune adults. Abnormal cell-surface display of the main variable cytoadherence ligand, PfEMP-1 (P. falciparum erythrocyte membrane protein-1), correlates with these findings. The abnormalities in PfEMP-1 display are associated with markers of erythrocyte senescence, and are greater in CC than in AC erythrocytes. Haemoglobin C might protect against malaria by reducing PfEMP-1-mediated adherence of parasitized erythrocytes, thereby mitigating the effects of their sequestration in the microvasculature. 相似文献