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91.
92.
Novel locus for autosomal dominant hereditary spastic paraplegia, on chromosome 8q. 总被引:11,自引:2,他引:9
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P Hedera S Rainier D Alvarado X Zhao J Williamson B Otterud M Leppert J K Fink 《American journal of human genetics》1999,64(2):563-569
Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous group of disorders characterized by insidiously progressive spastic weakness in the legs. Genetic loci for autosomal dominant HSP exist on chromosomes 2p, 14q, and 15q. These loci are excluded in 45% of autosomal dominant HSP kindreds, indicating the presence of additional loci for autosomal dominant HSP. We analyzed a Caucasian kindred with autosomal dominant HSP and identified tight linkage between the disorder and microsatellite markers on chromosome 8q (maximum two-point LOD score 5.51 at recombination fraction 0). Our results clearly establish the existence of a locus for autosomal dominant HSP on chromosome 8q23-24. Currently this locus spans 6.2 cM between D8S1804 and D8S1774 and includes several potential candidate genes. Identifying this novel HSP locus on chromosome 8q23-24 will facilitate discovery of this HSP gene, improve genetic counseling for families with linkage to this locus, and extend our ability to correlate clinical features with different HSP loci. 相似文献
93.
Michael S. Engel Diying Huang Abdulaziz S. Alqarni Chenyang Cai Mabel Alvarado Laura C.V. Breitkreuz Dany Azar 《Comptes Rendus Palevol》2017,16(1):5-11
A remarkably specialized parasitoid wasp of the family Scelionidae (Platygastroidea) is described and figured from mid-Cretaceous (Cenomanian) amber of the Hukawng Valley in northern Myanmar. Geoscelio mckellari Engel and Huang, gen. et sp. nov., is unique for its combination of a compact body, 12 antennal flagellomeres, a 1-2-2 tibial spur formula, a distinct malar sulcus, deeply impressed notauli, complete reduction of the wings, and basal crenulae on the metasomal terga and sterna, among many other features, and is placed within a separate tribe, Geoscelionini Engel and Huang, trib. nov. This is the first flightless species of Platygastroidea known from the Mesozoic, and its affinities with other Mesozoic and extant lineages are discussed. 相似文献
94.
J.R. Alvarado Bremer J. Mejuto F. Boán J.M. Rodríguez T.W. Greig 《Journal of experimental marine biology and ecology》2005,327(2):167-182
In species with high migratory potential, the genetic signal revealing population differentiation is often obscured by population admixture. To our knowledge, the explicit comparison of genetic samples from known spawning and feeding areas has not been conducted for any highly migratory pelagic fish species. This study examines the geographic heterogeneity of swordfish mitochondrial DNA (mtDNA) lineages within the Atlantic Ocean using 330 base pairs of sequence of the control region from 480 individuals. Hierarchical analyses of sequence variation were conducted to test whether samples from areas identified as the corresponding spawning and feeding grounds for the northwest (NW) Atlantic (Caribbean and Georges Banks-US northeast) and the South Atlantic (Brazil-Uruguay and Gulf of Guinea), were more closely related to each other than to samples from any other region, including the Mediterranean Sea, the Indian Ocean, and the Pacific Ocean. Phylogeographic analyses reveal that swordfish mtDNA phylogeny is characterized by incomplete lineage sorting and secondary contact of two highly divergent clades. However, despite this complex phylogenetic signature, results from an analysis of nucleotide diversity and from an analysis of molecular variance (AMOVA) were for the most part concordant and indicate that NW Atlantic and South Atlantic swordfish belong to separate populations. The mtDNA distinctiveness of NW Atlantic and South Atlantic swordfish populations is indicative of philopatric behavior in swordfish towards breeding and feeding areas. 相似文献
95.
Tito A. Wibowo Charles T. Gaskins Ruth C. Newberry Gary H. Thorgaard Jennifer J. Michal Zhihua Jiang 《International journal of biological sciences》2008,4(6):406-414
Bovine chromosome 14 (BTA14) has been widely explored for quantitative trait loci (QTL) and genes related to economically important traits in both dairy and beef cattle. We reviewed more than 40 investigations and anchored 126 QTL to the current genome assembly (Btau 4_0). Using this anchored QTL map, we observed that, in dairy cattle, the region spanning 0 – 10 Mb on BTA14 has the highest density QTL map with a total of 56 QTL, mainly for milk production traits. It is very likely that both somatic cell score (SCS) and clinical mastitis share some common QTL in two regions: 61.48 Mb - 73.84 Mb and 7.86 Mb – 39.55 Mb, respectively. As well, both ovulation rate and twinning rate might share a common QTL region from 34.16 Mb to 65.38 Mb. However, there are no common QTL locations in three pregnancy related phenotypes: non-return rate, pregnancy rate and daughter pregnancy rate. In beef cattle, the majority of QTL are located in a broad region of 15 Mb – 45 Mb on the chromosome. Functional genes, such as CRH, CYP11B1, DGAT1, FABP4 and TG, as potential candidates for some of these QTL, were also reviewed. Therefore, our review provides a standardized QTL map anchored within the current genome assembly, which would enhance the process of selecting positional and physiological candidate genes for many important traits in cattle. 相似文献
96.
Matute C 《Molecular neurobiology》2008,38(2):123-128
Intense ATP signaling through P2X7 purinergic receptors can lead to excitotoxicity, a feature which initiates neuronal demise
in experimental paradigms relevant to ischemia and to traumatic injury. In addition, recent data provide evidence that oligodendrocytes
also express P2X7 receptors that are activated under experimental pathological conditions involving white matter demise. Thus,
this receptor subtype is a promising target for the development of new drugs to prevent white matter damage in acute and chronic
diseases. 相似文献
97.
Daniel R. Matute Caroline J. Novak Jerry A. Coyne 《Evolution; international journal of organic evolution》2009,63(3):595-612
Drosophila santomea and D. yakuba are sister species that live on the African volcanic island of São Tomé, where they are ecologically isolated: D. yakuba inhabits low-altitude open and semiopen habitats while D. santomea lives in higher-elevation rain and mist forest. To determine whether this spatial isolation reflected differential preference for and tolerance of temperature, we estimated fitness components of both species at different temperatures as well as their behavioral preference for certain temperatures. At higher temperatures, especially 28°C, D. santomea was markedly inferior to D. yakuba in larval survival, egg hatchability, and longevity. Moreover, D. santomea females, unlike those of D. yakuba , become almost completely sterile after exposure to a temperature of 28°C, and conspecific males become semisterile. Drosophila santomea adults prefer temperatures 2–3°C lower than do adults of D. yakuba . Drosophila santomea , then, is poorly adapted to high temperature, partially explaining its restriction to cool, high habitats, which leads to extrinsic premating isolation and immigrant inviability. Rudimentary genetic analysis of the interspecific difference in egg hatchability and larval survival showed that these differences are due largely to cytoplasmic effects and to autosomal genes, with sex chromosomes playing little or no role. 相似文献
98.
Luís Cunha-Silva Filipe A. Almeida Paz Michaele J. Hardie Tito Trindade 《Inorganica chimica acta》2009,362(1):263-270
The crystalline compounds (Hbipy)2[Ge(C2O4)3] (1) and (Hphen)2[Ge(C2O4)3] · 2(H2O) (2) [Hbipy+ is the 2,2′-bipyridinium cation (C10H9N2), and Hphen+ is the 1,10′-phenathrolinium cation (C12H9N2)] were isolated from mild hydrothermal syntheses and their structures were elucidated from single-crystal X-ray diffraction. The two compounds were further characterised by vibrational spectroscopy (FT-IR and FT-Raman), thermogravimetric analysis (TGA) and CHN elemental composition. Compounds 1 and 2 comprise the tris(oxalato-O,O′)germanate dianion complex, [Ge(C2O4)3]2−, which co-crystallises with Hbipy+ (in 1), or Hphen+ and water molecules (in 2). In 1, the germanium oxalate anionic complex, [Ge(C2O4)3]2−, and the Hbipy+ organic residues interact mutually via N-H?O hydrogen bonding interactions, leading to supramolecular discrete hydrogen-bonded units which are further interconnected via π-π stacking. Compound 2, on the other hand, exhibits a more complex hydrogen bonding network due to the presence of the water molecules of crystallisation which, along with π-π stacking between neighbouring Hphen+ residues, mediate the crystal packing. 相似文献
99.
100.
Katia C. S. Figueiredo Helen C. Ferraz Cristiano P. Borges Tito L. M. Alves 《The protein journal》2009,28(5):224-232
The structural stability of metmyoglobin in organic solvents and cosolvents was investigated aiming the choice of a suitable
medium to perform its dissolution with maintenance of the native folding. The spectroscopic behavior of metmyoglobin solution
in UV–Visible and circular dichroism was used to evaluate the solubility and the secondary structure. The results were dependable
of the chemical structure of the organic compounds, their polarity and content, in the case of cosolvents. Protic solvents
showed better ability than the aprotic ones for the biomolecule dissolution, since they are able to establish hydrogen bonds.
Solvents with high polarity usually damage the secondary structure of the protein. Myoglobin was dissolved in pure methanol,
ethylene glycol and glycerol. The secondary structure was retained in some extent. The controlled addition of sodium dodecyl
sulfate to myoglobin aqueous solution changed the surface moiety of the protein. The complex was extracted to hexane with
efficiency of 77%. 相似文献