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41.
Rollmann SM Magwire MM Morgan TJ Ozsoy ED Yamamoto A Mackay TF Anholt RR 《Nature genetics》2006,38(7):824-829
The abundance of transposable elements and DNA repeat sequences in mammalian genomes raises the question of whether such insertions represent passive evolutionary baggage or may influence the expression of complex traits. We addressed this question in Drosophila melanogaster, in which the effects of single transposable elements on complex traits can be assessed in genetically identical individuals reared in controlled environments. Here we demonstrate that single P-element insertions in the intergenic region between the gustatory receptor 5a (Gr5a, also known as Tre) and trapped in endoderm 1 (Tre1), which encodes an orphan receptor, exert complex pleiotropic effects on fitness traits, including selective nutrient intake, life span, and resistance to starvation and heat stress. Mutations in this region interact epistatically with downstream components of the insulin signaling pathway. Transposon-induced sex-specific and sex-antagonistic effects further accentuate the complex influences that intergenic transposable elements can contribute to quantitative trait phenotypes. 相似文献
42.
Mailman MD Feolo M Jin Y Kimura M Tryka K Bagoutdinov R Hao L Kiang A Paschall J Phan L Popova N Pretel S Ziyabari L Lee M Shao Y Wang ZY Sirotkin K Ward M Kholodov M Zbicz K Beck J Kimelman M Shevelev S Preuss D Yaschenko E Graeff A Ostell J Sherry ST 《Nature genetics》2007,39(10):1181-1186
The National Center for Biotechnology Information has created the dbGaP public repository for individual-level phenotype, exposure, genotype and sequence data and the associations between them. dbGaP assigns stable, unique identifiers to studies and subsets of information from those studies, including documents, individual phenotypic variables, tables of trait data, sets of genotype data, computed phenotype-genotype associations, and groups of study subjects who have given similar consents for use of their data. 相似文献
43.
DMP1 mutations in autosomal recessive hypophosphatemia implicate a bone matrix protein in the regulation of phosphate homeostasis 总被引:14,自引:0,他引:14
Lorenz-Depiereux B Bastepe M Benet-Pagès A Amyere M Wagenstaller J Müller-Barth U Badenhoop K Kaiser SM Rittmaster RS Shlossberg AH Olivares JL Loris C Ramos FJ Glorieux F Vikkula M Jüppner H Strom TM 《Nature genetics》2006,38(11):1248-1250
Hypophosphatemia is a genetically heterogeneous disease. Here, we mapped an autosomal recessive form (designated ARHP) to chromosome 4q21 and identified homozygous mutations in DMP1 (dentin matrix protein 1), which encodes a non-collagenous bone matrix protein expressed in osteoblasts and osteocytes. Intact plasma levels of the phosphaturic protein FGF23 were clearly elevated in two of four affected individuals, providing a possible explanation for the phosphaturia and inappropriately normal 1,25(OH)2D levels and suggesting that DMP1 may regulate FGF23 expression. 相似文献
44.
Eubrachyurans not only exhibit a crab-like body shape, consisting of a mostly wide cephalothorax and a thin, shield-like pleon folded underneath it, but reportedly hold the pleon in this position with the use of specialized holding structures. To further our knowledge of the variability of these holding structures, and investigate their functionality, male and female crabs from five primary freshwater crab and five selected thoracotreme families were examined with stereomicroscopy. Exemplary specimens of each group were documented photographically and with micro-computed tomography to illustrate the holding structures in situ. The results show a press-button mechanism of variable shape in freshwater crabs, where divergent structures possibly support pleon attachment of different effectiveness. The press-button is present in the majority of basal heterotreme lineages, and is therefore regarded as an ancestral character of the Heterotremata. In the Thoracotremata, multiple holding mechanisms are identified: press-button, clasping apparatus, overhanging edge, and increased setae cover on sternal plates, with the last system probably only effective in terrestrial species, due to wet adhesion effects. The ancestral character state in the Thoracotremata is debatable, but most likely also a functional press-button was present. Each holding mechanism requires different pleon movements to engage and disengage. Additionally, in contrast to the most common press-button mechanism, divergent holding mechanisms tend to be present, and likely functional, in adult males and females. 相似文献
45.
Porco CC Baker E Barbara J Beurle K Brahic A Burns JA Charnoz S Cooper N Dawson DD Del Genio AD Denk T Dones L Dyudina U Evans MW Fussner S Giese B Grazier K Helfenstein P Ingersoll AP Jacobson RA Johnson TV McEwen A Murray CD Neukum G Owen WM Perry J Roatsch T Spitale J Squyres S Thomas P Tiscareno M Turtle EP Vasavada AR Veverka J Wagner R West R 《Nature》2005,434(7030):159-168
Titan, the largest moon of Saturn, is the only satellite in the Solar System with a substantial atmosphere. The atmosphere is poorly understood and obscures the surface, leading to intense speculation about Titan's nature. Here we present observations of Titan from the imaging science experiment onboard the Cassini spacecraft that address some of these issues. The images reveal intricate surface albedo features that suggest aeolian, tectonic and fluvial processes; they also show a few circular features that could be impact structures. These observations imply that substantial surface modification has occurred over Titan's history. We have not directly detected liquids on the surface to date. Convective clouds are found to be common near the south pole, and the motion of mid-latitude clouds consistently indicates eastward winds, from which we infer that the troposphere is rotating faster than the surface. A detached haze at an altitude of 500 km is 150-200 km higher than that observed by Voyager, and more tenuous haze layers are also resolved. 相似文献
46.
Larsson P Oyston PC Chain P Chu MC Duffield M Fuxelius HH Garcia E Hälltorp G Johansson D Isherwood KE Karp PD Larsson E Liu Y Michell S Prior J Prior R Malfatti S Sjöstedt A Svensson K Thompson N Vergez L Wagg JK Wren BW Lindler LE Andersson SG Forsman M Titball RW 《Nature genetics》2005,37(2):153-159
Francisella tularensis is one of the most infectious human pathogens known. In the past, both the former Soviet Union and the US had programs to develop weapons containing the bacterium. We report the complete genome sequence of a highly virulent isolate of F. tularensis (1,892,819 bp). The sequence uncovers previously uncharacterized genes encoding type IV pili, a surface polysaccharide and iron-acquisition systems. Several virulence-associated genes were located in a putative pathogenicity island, which was duplicated in the genome. More than 10% of the putative coding sequences contained insertion-deletion or substitution mutations and seemed to be deteriorating. The genome is rich in IS elements, including IS630 Tc-1 mariner family transposons, which are not expected in a prokaryote. We used a computational method for predicting metabolic pathways and found an unexpectedly high proportion of disrupted pathways, explaining the fastidious nutritional requirements of the bacterium. The loss of biosynthetic pathways indicates that F. tularensis is an obligate host-dependent bacterium in its natural life cycle. Our results have implications for our understanding of how highly virulent human pathogens evolve and will expedite strategies to combat them. 相似文献
47.
The seismologically defined boundary between the transition zone in the Earth's mantle (410-660 km depth) and the underlying lower mantle is generally interpreted to result from the breakdown of the gamma-spinel phase of olivine to magnesium-perovskite and magnesiowustite. Laboratory measurements of these transformations of olivine have determined that the phase boundary has a negative Clapeyron slope and does indeed occur near pressures corresponding to the base of the transition zone. But a computational study has indicated that, because of the presence of garnet minerals, multiple seismic discontinuities might exist near a depth of 660 km (ref. 4), which would alter the simple negative correlation of changes in temperature with changes in the depth of the phase boundary. In particular, garnet minerals undergo exothermic transformations near this depth, acting to complicate the phase relations and possibly effecting mantle convection processes in some regions. Here we present seismic evidence that supports the existence of such multiple transitions near a depth of 660 km beneath southern California. The observations are consistent with having been generated by garnet transformations coupling with the dissociation of the gamma-spinel phase of olivine. Temperature anomalies calculated from the imaged discontinuity depths--using Clapeyron slopes determined for the various transformations--generally match those predicted from an independent P-wave velocity model of the region. 相似文献
48.
M. Goldstein A. J. Friedhoff C. Simmons 《Cellular and molecular life sciences : CMLS》1959,15(2):80-81
Zusammenfassung Es wird eine neue Methode zur Bestimmung der Katecholamine im Harn beschrieben. Die Katecholamine werden im Harn acetyliert
und die Acetylderivate papierchromatographisch im Bush-?C?-System getrennt. Nach erfolgter Trennung werden die einzelnen Katecholamine
mit ?thylendiamin kondensiert und fluorimetrisch untersucht. Eine Spezifit?tserh?hung der Methode durch Anwendung doppelt
markierter Isotopen wird in Betracht gezogen.
相似文献
49.
Tasneem A. Khwaja Janet C. Varven Stephanie Pentecost Hema Pande 《Cellular and molecular life sciences : CMLS》1980,36(5):599-600
Summary Anticancer activity of certain highly cytotoxic alkaloids present in Korean mistletoe has been demonstrated in experimental animals. Unlike European mistletoe, no cytotoxic proteins were found in the Korean mistletoe.This work was presented at ACS/CSJ Chemical Congress, Honolulu, Hawaii, April 1–6, 1979.We are thankful to Jerome Foundation, Los Angeles, California for a generous grant for the support of this work. 相似文献
50.