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71.
A Sequence-Tagged Site Map of Human Chromosome 11 总被引:1,自引:0,他引:1
Michael W. Smith Stephen P. Clark Jane S. Hutchinson Yalin H. Wei Allan C. Churukian Lori B. Daniels Karin L. Diggle Michael W. Gen Anthony J. Romo Ying Lin Licia Selleri David L. McElligott Glen A. Evans 《Genomics》1993,17(3)
We report the construction of 370 sequence-tagged sites (STSs) that are detectable by PCR amplification under sets of standardized conditions and that have been regionally mapped to human chromosome 11. DNA sequences were determined by sequencing directly from cosmid templates using primers complementary to T3 and T7 promoters present in the cloning vector. Oligonucleotide PCR primers were predicted by computer and tested using a battery of genomic DNAs. Cosmids were regionally localized on chromosome 11 by using fluorescence in situ hybridization or by analyzing a somatic cell hybrid panel. Additional STSs corresponding to known genes and markers on chromosome 11 were also produced under the same series of standardized conditions. The resulting STSs provide uniform coverage of chromosome 11 with an average spacing of 340 kb. The DNA sequence determined for use in STS production corresponds to about 0.1% (116 kb) of chromosome 11 and has been analyzed for the presence of repetitive sequences, similarities to known genes and motifs, and possible exons. Computer analysis of this sequence has identified and therefore mapped at least eight new genes on chromosome 11. 相似文献
72.
Microsporidia, amitochondrial protists, possess a 70-kDa heat shock protein gene of mitochondrial evolutionary origin 总被引:13,自引:3,他引:10
Peyretaillade E; Broussolle V; Peyret P; Metenier G; Gouy M; Vivares CP 《Molecular biology and evolution》1998,15(6):683-689
An intronless gene encoding a protein of 592 amino acid residues with
similarity to 70-kDa heat shock proteins (HSP70s) has been cloned and
sequenced from the amitochondrial protist Encephalitozoon cuniculi (phylum
Microsporidia). Southern blot analyses show the presence of a single gene
copy located on chromosome XI. The encoded protein exhibits an N-terminal
hydrophobic leader sequence and two motifs shared by proteobacterial and
mitochondrially expressed HSP70 homologs. Phylogenetic analysis using
maximum likelihood and evolutionary distances place the E. cuniculi
sequence in the cluster of mitochondrially expressed HSP70s, with a higher
evolutionary rate than those of homologous sequences. Similar results were
obtained after cloning a fragment of the homologous gene in the closely
related species E. hellem. The presence of a nuclear targeting signal-like
sequence supports a role of the Encephalitozoon HSP70 as a molecular
chaperone of nuclear proteins. No evidence for cytosolic or endoplasmic
reticulum forms of HSP70 was obtained through PCR amplification. These data
suggest that Encephalitozoon species have evolved from an ancestor bearing
mitochondria, which is in disagreement with the postulated presymbiotic
origin of Microsporidia. The specific role and intracellular localization
of the mitochondrial HSP70-like protein remain to be elucidated.
相似文献
73.
74.
P. E. Brown O. F. Christensen H. E. Clough P. J. Diggle C. A. Hart S. Hazel R. Kemp A. J. H. Leatherbarrow A. Moore J. Sutherst J. Turner N. J. Williams E. J. Wright N. P. French 《Applied microbiology》2004,70(11):6501-6511
Humans are exposed to Campylobacter spp. in a range of sources via both food and environmental pathways. For this study, we explored the frequency and distribution of thermophilic Campylobacter spp. in a 10- by 10-km square rural area of Cheshire, United Kingdom. The area contains approximately 70, mainly dairy, farms and is used extensively for outdoor recreational activities. Campylobacter spp. were isolated from a range of environmental samples by use of a systematic sampling grid. Livestock (mainly cattle) and wildlife feces and environmental water and soil samples were cultured, and isolates were presumptively identified by standard techniques. These isolates were further characterized by PCR. Campylobacter jejuni was the most prevalent species in all animal samples, ranging from 11% in samples from nonavian wildlife to 36% in cattle feces, and was isolated from 15% of water samples. Campylobacter coli was commonly found in water (17%) and sheep (21%) samples, but rarely in other samples. Campylobacter lari was recovered from all sample types, with the exception of sheep feces, and was found in moderate numbers in birds (7%) and water (5%). Campylobacter hyointestinalis was only recovered from cattle (7%) and birds (1%). The spatial distribution and determinants of C. jejuni in cattle feces were examined by the use of model-based spatial statistics. The distribution was consistent with very localized within-farm or within-field transmission and showed little evidence of any larger-scale spatial dependence. We concluded that there is a potentially high risk of human exposure to Campylobacter spp., particularly C. jejuni, in the environment of our study area. The prevalence and likely risk posed by C. jejuni-positive cattle feces in the environment diminished as the fecal material aged. After we took into account the age of the fecal material, the absence or presence of rain, and the presence of bird feces, there was evidence of significant variation in the prevalence of C. jejuni-positive cattle feces between grazing fields but no evidence of spatial clustering beyond this resolution. The spatial pattern of C. jejuni is therefore consistent with that for an organism that is ubiquitous in areas contaminated with cattle feces, with a short-scale variation in infection intensity that cannot be explained solely by variations in the age of the fecal material. The observed pattern is not consistent with large-scale transmission attributable to watercourses, wildlife territories, or other geographical features that transcend field and farm boundaries. 相似文献
75.
76.
Epidermal growth factor, but not insulin, stimulates tyrosine phosphorylation of an endogenous protein of Mr 95,000 in triton extracts of human placental syncytiotrophoblast membranes. 总被引:1,自引:1,他引:0 下载免费PDF全文
1. Triton extracts of syncytiotrophoblast membranes were incubated with [gamma-32P]ATP, MgCl2 and MnCl2. Addition of epidermal growth factor (EGF) resulted in increased phosphorylation not only of the EGF receptor and a Mr-35,000 protein as previously described, but also a protein of Mr 95,000 on both tyrosine and serine residues. In addition, a small increase in the phosphorylation of a protein of Mr 105,000 was observed. Spermine had a similar effect on the phosphorylation of the Mr-95,000 protein, without affecting the phosphorylation of the other proteins. In the absence of MnCl2, the effect of spermine on the phosphorylation of Mr-95,000 protein was still evident, whereas that of EGF was greatly diminished. 2. The Mr-95,000 protein bound poorly to wheat-germ-lectin-Sepharose and was not precipitated by antisera specific for insulin and EGF receptors. The protein continued to exhibit serine and tyrosine phosphorylation on addition of [gamma-32P]ATP, MgCl2 and MnCl2 to a glycoprotein-depleted fraction prepared by chromatography on wheat-germ-lectin-Sepharose. The extent of phosphorylation was no longer increased by spermine or EGF, but was inhibited by heparin. 3. It is suggested that the Mr-95,000 protein not only is a possible direct substrate for the EGF-receptor (but not the insulin receptor) tyrosine kinase but is a substrate for other endogenous kinases, including a protein tyrosine kinase which is probably not a glycoprotein, and a protein serine kinase with properties similar to those of casein kinase II. 相似文献
77.
Collier SR Diggle MD Heffernan KS Kelly EE Tobin MM Fernhall B 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(10):2846-2852
Previous research has shown significantly lower arterial distensibility (AD) after resistance exercise (RE) yet higher AD after aerobic exercise (AE). These changes may be related to exercise-induced differences in vasodilatory capacity. The purpose of this study was to investigate the vasodilatory and AD responses to acute AE and RE. Forearm blood flow (FBF) during reactive hyperemia (RH) was assessed before and 60 minutes after exercise, whereas aortic and femoral pulse wave velocity was measured as an index of arterial stiffness pre, 40, and 60 minutes after an acute bout of AE (30-minute leg ergometry at 65% of VO2peak) and RE (3 sets, 10 reps; upper and lower body at 65% 1 repetition maximum) in 10 male subjects (24.9 ± 0.86 years). Area under the curve (AUC) was employed to determine differences in flow. After the intervention, we found that central pulse wave velocity decreased 8% after AE and remained depressed at this level through 60 minutes of observation, whereas RE increased central pulse wave velocity 9.8% from pre to 40 and 60 minutes postexercise. Area under the curve for FBF-RH significantly increased 38% after RE, yet there was no significant change after AE. Forearm vasodilatory capacity increased after acute RE but not after acute AE. This suggests that changes in AD may be disassociated from changes in vasodilatory capacity after acute exercise. Further, in a direct comparison of RE vs. AE, we have shown that RE has greater increases in limb blood flow and augments postexercise hypotension greater at 40 minutes postexercise when compared to AE. 相似文献
78.
P. K. Diggle N. J. Abrahamson R. L. Baker M. G. Barnes T. L. Koontz C. R. Lay J. S. Medeiros J. L. Murgel M. G. M. Shaner H. L. Simpson C. C. Wu D. L. Marshall 《Annals of botany》2010,106(2):309-319
Background and Aims
Variability in embryo development can influence the rate of seed maturation and seed size, which may have an impact on offspring fitness. While it is expected that embryo development will be under maternal control, more controversial hypotheses suggest that the pollen donor and the embryo itself may influence development. These latter possibilities are, however, poorly studied. Characteristics of 10-d-old embryos and seeds of wild radish (Raphanus sativus) were examined to address: (a) the effects of maternal plant and pollen donor on development; (b) the effects of earlier reproductive events (pollen tube growth and fertilization) on embryos and seeds, and the influence of embryo size on mature seed mass; (c) the effect of water stress on embryos and seeds; (d) the effect of stress on correlations of embryo and seed characteristics with earlier and later reproductive events and stages; and (e) changes in maternal and paternal effects on embryo and seed characteristics during development.Methods
Eight maternal plants (two each from four families) and four pollen donors were crossed and developing gynoecia were collected at 10 d post-pollination. Half of the maternal plants experienced water stress. Characteristics of embryos and seeds were summarized and also compared with earlier and later developmental stages.Key Results
In addition to the expected effects of the maternal plants, all embryo characters differed among pollen donors. Paternal effects varied over time, suggesting that there are windows of opportunity for pollen donors to influence embryo development. Water-stress treatment altered embryo characteristics; embryos were smaller and less developed. In addition, correlations of embryo characteristics with earlier and later stages changed dramatically with water stress.Conclusions
The expected maternal effects on embryo development were observed, but there was also evidence for an early paternal role. The relative effects of these controls may change over time. Thus, there may be times in development when selection on the maternal, paternal or embryo contributions to development are more and less likely. 相似文献79.
Lucas A Smolders Bj?rn P Meij David Onis Frank M Riemers Niklas Bergknut Richard Wubbolts Guy CM Grinwis Martin Houweling Marian JA Groot Koerkamp Dik van Leenen Frank CP Holstege Herman AW Hazewinkel Laura B Creemers Louis C Penning Marianna A Tryfonidou 《Arthritis research & therapy》2013,15(1):R23
Introduction
Early degeneration of the intervertebral disc (IVD) involves a change in cellular differentiation from notochordal cells (NCs) in the nucleus pulposus (NP) to chondrocyte-like cells (CLCs). The purpose of this study was to investigate the gene expression profiles involved in this process using NP tissue from non-chondrodystrophic and chondrodystrophic dogs, a species with naturally occurring IVD degeneration.Methods
Dual channel DNA microarrays were used to compare 1) healthy NP tissue containing only NCs (NC-rich), 2) NP tissue with a mixed population of NCs and CLCs (Mixed), and 3) NP tissue containing solely CLCs (CLC-rich) in both non-chondrodystrophic and chondrodystrophic dogs. Based on previous reports and the findings of the microarray analyses, canonical Wnt signaling was further evaluated using qPCR of relevant Wnt target genes. We hypothesized that caveolin-1, a regulator of Wnt signaling that showed significant changes in gene expression in the microarray analyses, played a significant role in early IVD degeneration. Caveolin-1 expression was investigated in IVD tissue sections and in cultured NCs. To investigate the significance of Caveolin-1 in IVD health and degeneration, the NP of 3-month-old Caveolin-1 knock-out mice was histopathologically evaluated and compared with the NP of wild-type mice of the same age.Results
Early IVD degeneration involved significant changes in numerous pathways, including Wnt/β-catenin signaling. With regard to Wnt/β-catenin signaling, axin2 gene expression was significantly higher in chondrodystrophic dogs compared with non-chondrodystrophic dogs. IVD degeneration involved significant down-regulation of axin2 gene expression. IVD degeneration involved significant down-regulation in Caveolin-1 gene and protein expression. NCs showed abundant caveolin-1 expression in vivo and in vitro, whereas CLCs did not. The NP of wild-type mice was rich in viable NCs, whereas the NP of Caveolin-1 knock-out mice contained chondroid-like matrix with mainly apoptotic, small, rounded cells.Conclusions
Early IVD degeneration involves down-regulation of canonical Wnt signaling and Caveolin-1 expression, which appears to be essential to the physiology and preservation of NCs. Therefore, Caveolin-1 may be regarded an exciting target for developing strategies for IVD regeneration. 相似文献80.
Eyal Goldstein Joseph J. Erinjery Gerardo Martin Anuradhani Kasturiratne Dileepa Senajith Ediriweera Hithanadura Janaka de Silva Peter Diggle David Griffith Lalloo Kris A. Murray Takuya Iwamura 《PLoS neglected tropical diseases》2021,15(1)
Snakebite causes more than 1.8 million envenoming cases annually and is a major cause of death in the tropics especially for poor farmers. While both social and ecological factors influence the chance encounter between snakes and people, the spatio-temporal processes underlying snakebites remain poorly explored. Previous research has focused on statistical correlates between snakebites and ecological, sociological, or environmental factors, but the human and snake behavioral patterns that drive the spatio-temporal process have not yet been integrated into a single model. Here we use a bottom-up simulation approach using agent-based modelling (ABM) parameterized with datasets from Sri Lanka, a snakebite hotspot, to characterise the mechanisms of snakebite and identify risk factors. Spatio-temporal dynamics of snakebite risks are examined through the model incorporating six snake species and three farmer types (rice, tea, and rubber). We find that snakebites are mainly climatically driven, but the risks also depend on farmer types due to working schedules as well as species present in landscapes. Snake species are differentiated by both distribution and by habitat preference, and farmers are differentiated by working patterns that are climatically driven, and the combination of these factors leads to unique encounter rates for different landcover types as well as locations. Validation using epidemiological studies demonstrated that our model can explain observed patterns, including temporal patterns of snakebite incidence, and relative contribution of bites by each snake species. Our predictions can be used to generate hypotheses and inform future studies and decision makers. Additionally, our model is transferable to other locations with high snakebite burden as well. 相似文献