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Quantitative trait loci (QTLs) for body weight and tail length are mapped in an F2 population of 927 C57BL/6J × DBA/2J mice. We test the concordance between the locations of the mapped QTLs with those detected
by changes of marker frequency under artificial selection in a previous experiment with the same base population. The directions
of effects of the QTLs are generally in agreement, and in many cases significant QTLs are found in similar map positions,
but there are also discrepancies between the two experiments. There are indications of age-specific QTL effects on growth.
For body weight traits, the genetic variation in the F2 appears to result from many loci with relatively small effects. For tail length at 10 weeks, however, a single QTL on Chromosome
(Chr) 1 with a peak LOD score of ∼33 contributes most of the genetic variation detected, changes the trait value by about
6%, and explains about 20% of the phenotypic variance of the trait.
Received: 4 August 1998 / Accepted: 17 November 1998 相似文献
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The itinerary of W. H. Camp and his assistants in Ecuador has been reconstructed from fieldbooks deposited in the archives of the library at The New York Botanical Garden. The visited localities are listed according to collection numbers, an alphabetical list of the localities with geographical coordinates or best approximation is provided, and a map is presented showing the area where most numbers were collected. 相似文献
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Clarissa C. Parker Riyan Cheng Greta Sokoloff Jackie E. Lim Andrew D. Skol Mark Abney Abraham A. Palmer 《Mammalian genome》2011,22(9-10):563-571
The present study measured variation in body weight using a combined analysis in an F2 intercross and an F34 advanced intercross line (AIL). Both crosses were derived from inbred LG/J and SM/J mice, which were selected for large and small body size prior to inbreeding. Body weight was measured at 62 (±5) days of age. Using an integrated GWAS and forward model selection approach, we identified 11 significant QTLs that affected body weight on ten different chromosomes. With these results we developed a full model that explained over 18% of the phenotypic variance. The median 1.5-LOD support interval was 5.55 Mb, which is a significant improvement over most prior body weight QTLs. We identified nonsynonymous coding SNPs between LG/J and SM/J mice in order to further narrow the list of candidate genes. Three of the genes with nonsynonymous coding SNPs (Rad23b, Stk33, and Anks1b) have been associated with adiposity, waist circumference, and body mass index in human GWAS, thus providing evidence that these genes may underlie our QTLs. Our results demonstrate that a relatively small number of loci contribute significantly to the phenotypic variance in body weight, which is in marked contrast to the situation in humans. This difference is likely to be the result of strong selective pressure and the simplified genetic architecture, both of which are important advantages of our system. 相似文献
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In this study we describe the contribution of matrilineal and patrilineal effects on the adiposity, body weight, and on the
weights of individual fat pads in F2 male mice derived from an SWR/J × AKR/J cross. AKR/J mice become obese after 12 weeks on a high-fat diet, whereas SWR/J mice
remain relatively lean. Here we report that mice with AKR maternal and AKR paternal grandmothers have significantly larger
epidydimal and retroperitoneal fat pads than those with SWR maternal and paternal grandmothers. However, grandparental strain
had no effect on the overall adiposity (AI) or the weights of the inguinal, subcutaneous or mesenteric fat pads. The strain
of the paternal grandparents had a small but significant effect on body weight. These effects can be attributed to in utero
effects, imprinting effects, cytoplasmic and/or Y chromosome transmission of factors controlling body fat. We also describe
the presence of a quantitative trait locus (QTL) on Chromosome X, close to DXMit174, which is linked to adiposity, body weight, and to the weights of the individual fat depots. However, this QTL is not responsible
for the grandparental strain effects described above.
Received: 3 March 1997 / Accepted: 5 May 1997 相似文献
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Robert Hitzemann Laura Cipp Kristin Demarest Elham Mahjubi James McCaughran Jr. 《Mammalian genome》1998,9(12):956-962
Moderate doses of ethanol (1–2 g/kg) markedly increase locomotor activity in some inbred mouse strains, for example, the
DBA/2J (D2), but have relatively little effect in other strains, for example, the C57BL/6J (B6). In the present study, we
conducted a genome-wide search in a B6D2 F2 intercross (N = 925) for quantitative trait loci (QTLs) associated with the locomotor response. A QTL with a LOD score of
8.4 was detected on Chromosome (Chr) 2; this QTL accounted for 11.4% of the phenotypic variance and approximately 30% of the
genetic variance. The QTL on Chr 2 is in the same general region as QTLs previously described for ethanol preference/consumption
(Rodriguez et al. Alcohol Clin Exp Res 19, 367, 1995; Melo et al. Nat Genet 13, 147, 1996; Phillips et al. Mamm Genome, in
press), acute ethanol withdrawal (Buck et al. J. Neurosci 17, 3946, 1997) and nitrous oxide withdrawal severity (Belknap et
al. Behav Genet 23, 213, 1993). A logical candidate gene in the region of interest is the enzyme which synthesizes GABA, glutamic
acid decarboxylase 1 (GadI).
Received: 15 September 1998 / Accepted: 8 October 1998 相似文献
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Antonella Gradogna Paola Imbrici Giovanni Zifarelli Antonella Liantonio Diana Conte Camerino Michael Pusch 《生物化学与生物物理学报:生物膜》2014
CLC-K chloride channels and their subunit, barttin, are crucial for renal NaCl reabsorption and for inner ear endolymph production. Mutations in CLC-Kb and barttin cause Bartter syndrome. Here, we identified two adjacent residues, F256 and N257, that when mutated hugely alter in Xenopus oocytes CLC-Ka's biphasic response to niflumic acid, a drug belonging to the fenamate class, with F256A being potentiated 37-fold and N257A being potently blocked with a KD ~ 1 μM. These residues are localized in the same extracellular I–J loop which harbors a regulatory Ca2 + binding site. This loop thus can represent an ideal and CLC-K specific target for extracellular ligands able to modulate channel activity. Furthermore, we demonstrated the involvement of the barttin subunit in the NFA potentiation. Indeed the F256A mutation confers onto CLC-K1 a transient potentiation induced by NFA which is found only when CLC-K1/F256A is co-expressed with barttin. Thus, in addition to the role of barttin in targeting and gating, the subunit participates in the pharmacological modulation of CLC-K channels and thus represents a further target for potential drugs. 相似文献
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Jay Shendure Justine A. Melo Kara Pociask Rachel Derr Lee M. Silver 《Mammalian genome》1998,9(10):812-815
We report on the observation of sex-restricted, non-Mendelian inheritance over a region of mouse Chromosome (Chr) 11, occurring
in the offspring of crosses between two commonly used Mus musculus-derived inbred strains, C57BL/6J and DBA/2J. In the surviving backcross progeny of reciprocal matings between (C57BL/6J ×
DBA/2J)F1 hybrids and the C57BL/6J parental strain, we observed the preferential appearance of C57BL/6J alleles along a region of Chr
11. The deviation from Mendelian predictions was observed only in female offspring from both reciprocal backcrosses, and not
in males from either cross. The sex-specificity of the observed non-Mendelian inheritance points to an explanation based on
embryonic or neonatal lethality. Our data add to previously obtained evidence for a Chr 11 locus or loci with sex-specific
and allele-specific effects on viability.
Received: 19 December 1997 / Accepted: 10 June 1998 相似文献
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Sahotra Sarkar 《Biology & philosophy》1992,7(4):385-409
This paper analyzes the interaction between science, philosophy and politics (including ideology) in the early work of J. B. S. Haldane (from 1922 to 1937). This period is particularly important, not only because it is the period of Haldane's most significant biological work (both in biochemistry and genetics), but also because it is during this period that his philosophical and political views underwent their most significant transformation. His philosophical stance first changed from a radical organicism to a position far more compatible with mechanical materialism. The primary intellectual influence that was responsible for this shift was that of F. G. Hopkins. Later, Haldane came to accept Marxism and its official metaphysics, dialectical materialism, a move that let him accept the materialist conception of the world while still maintaining a resolute distance from mechanism. Throughout all these changes, what is most obvious is the influence of science on Haldane's philosophical views. An influence in the opposite direction is far less apparent.Parts of this paper are extracted from a longer work which concerns the interactions between philosophy and science throughout Haldane's scientific career (Sarkar forthcoming). The general conclusions reached here, from a consideration of Haldane's work only from 1922 to 1937 (see Section 6), remain the same for the rest of his life, as is detailed in the longer work. Thanks are due to R. S. Cohen, J. F. Crow, A. R. Fersht, J. Maynard Smith, R. C. Olby, D. Paul, M. Ruse, J. Stachel and S. Sturdy for helpful discussions and comments and criticism of the positions outlined in this paper. This is Contribution No. BTBG-92-4 from the Theoretical Biology Group, Boston University. 相似文献
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P. Burtin Christian Jay-Allemand Jean-Paul Charpentier Gérard Janin 《Trees - Structure and Function》1998,12(5):258-264
Radial distribution of soluble phenolics was investigated at different heights in stems of Juglans nigra, J. regia and hybrids J. nigra 23 × J. regia. Four major phenolic compounds were studied: hydrojuglone glucoside (HJG), quercitrin (QUER) and two unknown compounds
characterized as two ellagic acid derivatives E1 and E2. HJG and E1 content increased gradually in the sapwood, peaked in
the sapwood-heartwood transition zone, and decreased drastically in the heartwood. QUER was accumulated preferentially around
the transition zone, and its content was relatively low in the outer part of the sapwood and in the inner part of the heartwood.
E2 content was low in the sapwood and increased in the heartwood. The heartwood formation was marked by the accumulation of
new soluble compounds. The relationship between wood extractives and wood colour were evaluated and discussed. HJG was considered
to be a major precursor of heartwood colour providing chromophores through hydrolysis (deglucosylation), oxidation and polymerization
processes.
Received: 2 September 1997 / Accepted: 23 November 1997 相似文献
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