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11.
Jin-Yuan Fan John C. Means Edward S. Bjes Jeffrey L. Price 《Molecular and cellular biology》2015,35(14):2414-2424
Drosophila DBT and vertebrate CKIε/δ phosphorylate the period protein (PER) to produce circadian rhythms. While the C termini of these orthologs are not conserved in amino acid sequence, they inhibit activity and become autophosphorylated in the fly and vertebrate kinases. Here, sites of C-terminal autophosphorylation were identified by mass spectrometry and analysis of DBT truncations. Mutation of 6 serines and threonines in the C terminus (DBTC/ala) prevented autophosphorylation-dependent DBT turnover and electrophoretic mobility shifts in S2 cells. Unlike the effect of autophosphorylation on CKIδ, DBT autophosphorylation in S2 cells did not reduce its in vitro activity. Moreover, overexpression of DBTC/ala did not affect circadian behavior differently from wild-type DBT (DBTWT), and neither exhibited daily electrophoretic mobility shifts, suggesting that DBT autophosphorylation is not required for clock function. While DBTWT protected S2 cells and larvae from UV-induced apoptosis and was phosphorylated and degraded by the proteasome, DBTC/ala did not protect and was not degraded. Finally, we show that the HSP-90 cochaperone spaghetti protein (SPAG) antagonizes DBT autophosphorylation in S2 cells. These results suggest that DBT autophosphorylation regulates cell death and suggest a potential mechanism by which the circadian clock might affect apoptosis. 相似文献
12.
Xiuling Li Songbai Yang Zhonglin Tang Kui Li Max F. Rothschild Bang Liu Bin Fan 《Animal genetics》2014,45(3):329-339
Due to the direction, intensity, duration and consistency of genetic selection, especially recent artificial selection, the production performance of domestic pigs has been greatly changed. Therefore, we reasoned that there must be footprints or selection signatures that had been left during domestication. In this study, with porcine 60K BeadChip genotyping data from both commercial Large White and local Chinese Tongcheng pigs, we calculated the extended haplotype homozygosity values of the two breeds using the long‐range haplotype method to detect selection signatures. We found 34 candidate regions, including 61 known genes, from Large White pigs and 25 regions comprising 57 known genes from Tongcheng pigs. Many selection signatures were found on SSC1, SSC4, SSC7 and SSC14 regions in both populations. According to quantitative trait loci and network pathway analyses, most of the regions and genes were linked to growth, reproduction and immune responses. In addition, the average genetic differentiation coefficient FST was 0.254, which means that there had already been a significant differentiation between the breeds. The findings from this study can contribute to further research on molecular mechanisms of pig evolution and domestication and also provide valuable references for improvement of their breeding and cultivation. 相似文献
13.
Yuhui He Makusu Tsutsui Ralph H. Scheicher Chun Fan Masateru Taniguchi Tomoji Kawai 《Biophysical journal》2013
Experiments using nanopores demonstrated that a salt gradient enhances the capture rate of DNA and reduces its translocation speed. These two effects can help to enable electrical DNA sequencing with nanopores. Here, we provide a quantitative theoretical evaluation that shows the positive net charges, which accumulate around the pore entrance due to the salt gradient, are responsible for the two observed effects: they reinforce the electric capture field, resulting in promoted molecule capture rate; and they induce cationic electroosmotic flow through the nanopore, thus significantly retarding the motion of the anionic DNA through the nanopore. Our multiphysical simulation results show that, during the polymer trapping stage, the former effect plays the major role, thus resulting in promoted DNA capture rate, while during the nanopore-penetrating stage the latter effect dominates and consequently reduces the DNA translocation speed significantly. Quantitative agreement with experimental results has been reached by further taking nanopore wall surface charges into account. 相似文献
14.
A comparative analysis of photosynthetic characteristics of hulless barley at two altitudes on the Tibetan Plateau 总被引:1,自引:0,他引:1
To determine the photosynthetic characteristics of C3 plants and their sensitivity to CO2 at different altitudes on the Tibetan Plateau, hulless barley (Hordeum vulgare L. ssp. vulgare) was grown at altitudes of 4,333 m and 3,688 m. Using gas-exchange measurements, photosynthetic parameters were simulated,
including the maximum net photosynthesis (P
max) and the apparent quantum efficiency (α). Plants growing at higher altitude had higher net photosynthetic rates (P
N), photosynthesis parameters (P
max and α) and sensitivities to CO2 enhancement than plants growing at lower altitude on the Tibetan Plateau. The enhancements of P
N, P
max, and α for plants growing at higher altitude, corresponding with 10 μmol(CO2) mol−1 increments, were approximately 0.20∼0.45%, 0.05∼0.20% and 0.12∼0.36% greater, respectively, than for plants growing at lower
altitude, respectively, where CO2 levels rose from 10 to 170 μmol(CO2) mol−1. Therefore, on the Tibetan Plateau, the changes in the photosynthetic capacities and the photosynthetic sensitivities to
CO2 observed in the C3 plants grown above 3,688 m are likely to increase with altitude despite the decreasing CO2 partial pressure. 相似文献
15.
From 1974 to 1989, a total of 24,500 aborigines at 67 villages in ten mountainous districts/towns in Taiwan were examined for the Taiwan Taenia infection and 12% were found to be infected. In order to define the clinical manifestations of taeniasis caused by the Taiwan Taenia, 1661 aborigines in ten mountainous districts were surveyed. The overall clinical rate was 76%. The clinical rate was highest among Atayal aborigines (81%), followed by Bunun (66%) and Yami (61%) aborgines and lowest among Ami aborigines (40%). Among 1153 infected people, 10% had passed gravid segments in the faeces for less than 1 year, 24% for 1-3 years, 17% for 4-5 years, 23% for 6-10 years, 16% for 11-20 years, 7% for 21-30 years, and 3% over 30 years. Twenty-six occurrences of gastrointestinal and neurological symptoms were reported by 1258 infected persons. Passing proglottides in the faeces (95%) was the most frequent sign, followed by pruritis ani (77%), nausea (46%), abdominal pain (45%), dizziness (42%), increased appetite (30%), headache (26%), etc. 相似文献
16.
Production and characterization of antibodies against HT-2 toxin and T-2 tetraol tetraacetate. 总被引:1,自引:1,他引:0 下载免费PDF全文
Three new immunogens which were prepared by conjugation of the carboxymethyl oxime (CMO) derivatives of HT-2 toxin, T-2 tetraol (T-2 4ol), and T-2 tetraol tetraacetate (T-2 4Ac) to bovine serum albumin (BSA) were tested for the production of antibodies against the major metabolites of T-2 toxin. Antibodies against HT-2 toxin and T-2 4Ac were obtained from rabbits 5 to 10 weeks after immunizing the animals with CMO-HT-2-BSA and CMO-T-2 4Ac-BSA conjugates. Immunization with CMO-T-2 4ol-BSA resulted in no antibody against T-2 4ol. The antibody produced against HT-2 toxin had great affinity for HT-2 toxin as well as good cross-reactivity with T-2 toxin. The relative cross-reactivities of anti-HT-2 toxin antibody with HT-2 toxin, T-2 toxin, iso-T-2 toxin, acetyl-T-2 toxin, 3'-OH HT-2, 3'-OH T-2, T-2 triol, and 3'-OH acetyl-T-2, were 100, 25, 10, 3.3, 0.25, 0.15, 0.12 and 0.08%, respectively. Antibody against CMO-T-2 4Ac was very specific for T-2 4Ac and had less than 0.1% cross-reactivity with T-2 toxin, HT-2 toxin, acetyl-T-2 toxin, diacetoxyscirpenol, deoxynivalenol, and deoxynivalenol triacetate as compared with T-2 4Ac. The detection limits for HT-2 toxin and T-2 4ol by radioimmunoassay were approximately 0.1 and 0.5 ng per assay, respectively. 相似文献
17.
An electrophoretic karyotype for Schizosaccharomyces pombe by pulsed field gel electrophoresis. 总被引:44,自引:25,他引:19 下载免费PDF全文
C L Smith T Matsumoto O Niwa S Klco J B Fan M Yanagida C R Cantor 《Nucleic acids research》1987,15(11):4481-4489
The three chromosomal DNAs of S. pombe have been fractionated by pulsed field gel electrophoresis. The resulting molecular karyotype will greatly speed gene mapping in this organism, and it indicates that the separation range of the technique extends to DNA molecules as large as 9,000,000 base pairs. 相似文献
18.
记辽宁东部新鳞齿鱼属一新种 总被引:1,自引:0,他引:1
本文记述了产自辽宁东部红庙子盆地下桦皮甸子组的新鳞齿鱼属—新种——Neolepidotes liaodongensis sp. nov..根据新材料,将 Neolepidotes 与 Lepidotes 等属作了补充比较,增订了新鳞齿鱼属的特征. 相似文献
19.
The mutagenic potencies of 3 purine analogs were determined in the ad-3 forward-mutation test in growing cultures of heterokaryon 59 (H-59), a nucleotide excision repair-deficient (uvs-2/uvs-2) 2-component heterokaryon of Neurospora crassa. Two N-hydroxylaminopurines, 2-amino-6-N-hydroxylaminopurine (AHA) and 6-N-hydroxylaminopurine (HAP), were potent and strong mutagens, respectively, whereas 2-aminopurine (AP) was a moderate mutagen. Dose-response curves showed that AHA and HAP were about equally mutagenic at low doses but that AHA was more mutagenic than HAP at high doses. Comparison of these results in H-59 with our earlier results in heterokaryon 12 (H-12) of N. crassa, which is identical to H-59 except for being DNA-repair-proficient (uvs-2+/uvs-2+), shows that the defect in nucleotide excision repair due to uvs-2 has little or no effect on the mutagenic potencies of these 3 purine analogs. Therefore, the nucleotide excision-repair pathway in N. crassa that is deficient in H-59 does not appear to have a major role in the repair of pre-mutational lesions induced by these 3 purine analogs. On the other hand, based on the controls of these experiments, the frequency of spontaneous ad-3 mutants was 4 greater in H-59 than in H-12. This result suggests that the nucleotide excision-repair pathway in N. crassa that is inactivated by the uvs-2 mutation has a major role in the repair of lesions that would lead to spontaneous mutation at the ad-3+ region if they were not repaired. 相似文献
20.
Level of protein kinase C activity correlates directly with resistance to adriamycin in murine fibrosarcoma cells 总被引:3,自引:0,他引:3
In this report, we demonstrate a direct correlation between protein kinase C (PKC) activity and adriamycin (ADR) resistance in mouse fibrosarcoma cells. PKC activity was measured in four murine UV-2237M fibrosarcoma cell lines that differed in the degrees to which they expressed resistance to ADR, which is an inhibitor of PKC. A comparison of the four cell lines revealed a positive correlation between the level of PKC activity and resistance to ADR. Incubation of the cells with the PKC inhibitor H-7 produced a partial reversal of ADR resistance. Taken together, these results suggest a role for PKC in the mechanism of ADR resistance. 相似文献