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121.
Phylogenetic analysis of two putative Nosema isolates from Cruciferous Lepidopteran pests in Taiwan 总被引:1,自引:0,他引:1
In this study, a new microsporidian, PX2, was isolated from the diamondback moth, Plutella xylostella, and then compared with another isolate (PX1), and with Nosema spodopterae and N. bombycis. Sequence data showed that the rRNA gene organizations of PX1 and PX2 exhibited a typical Nosema-specific organization: 5'-LSUrRNA (large subunit ribosomal RNA)-ITS (internal transcribed spacer)-SSUrRNA-IGS (intergenic spacer)-5S-3'. Phylogenetic analysis (maximum likelihood, neighbor joining, maximum parsimony, and Bayesian analysis) of the LSUrRNA and SSUrRNA gene sequences, and the sequences of the alpha-tubulin, beta-tubulin, and RPB1 (DNA dependent RNA polymerase II largest subunit) genes found that PX1 was closer to N. bombycis and N. spodopterae than to PX2. Comparison of the identities of the rRNA domains and of the other three genes showed a high divergence in the sequences of the rRNA spacer regions (ITS and IGS). This is consistent with the hypothesis that PX2, if not PX1, might represent a new Nosema species. 相似文献
122.
The selective RNA-binding protein quaking I (QKI) is necessary and sufficient for promoting oligodendroglia differentiation 总被引:1,自引:0,他引:1
Chen Y Tian D Ku L Osterhout DJ Feng Y 《The Journal of biological chemistry》2007,282(32):23553-23560
Quaking I (QKI) is a selective RNA-binding protein essential for myelination of the central nervous system. Three QKI isoforms with distinct C termini and subcellular localization, namely QKI-5, QKI-6, and QKI-7, are expressed in oligodendroglia progenitor cells (OPCs) prior to the initiation of myelin formation and implicated in promoting oligodendrocyte lineage development. However, the functional requirement for each QKI isoform and the mechanisms by which QKI isoforms govern OPC development still remain elusive. We report here that exogenous expression of each QKI isoform is sufficient to enhance differentiation of OPCs with different efficiency, which is abolished by a point mutation that abrogates the RNA binding activity of QKI. Reciprocally, small interfering RNA-mediated QKI knockdown blocks OPC differentiation, which can be partly rescued by QKI-5 and QKI-6 but not by QKI-7, indicating the differential requirement of QKI isoform function in advancing OPC differentiation. Furthermore, we found that abrogation of OPC differentiation, as a result of QKI deficiency, is not due to altered proliferation capacity or cell cycle progression. These results indicate that QKI isoforms are necessary and sufficient for promoting OPC development, which must involve direct influence of QKI on differentiation/maturation of OPCs independent of cell cycle exit, likely via regulating the expression of the target mRNAs of QKI that support OPC differentiation. 相似文献
123.
A fluorescent method was developed for the detection of unpaired and mismatched DNAs using a MutS-fluorophore conjugate. The fluorophore, 2-(4'-(iodoacetoamido)anilino) naphthalene-6-sulfonic acid (IAANS), was site-specifically attached to the 469 position of Thermus aquaticus (Taq.) MutS mutant (C42A/T469C). The fluorophore labeled residue located at the dimer interface of the protein undergoes a drastic conformational change upon binding with mismatched DNA. The close proximity of the two identical fluorescent molecules presumably causes the self-quenching of the fluorophore, since fluorescence emission of the biosensor decreases with increasing concentrations of mismatched DNA. The order of binding affinity for each unpaired and mismatched DNA obtained by this method was DeltaT (Kd=52 nM)>GT (62 nM)>DeltaC (130 nM)>CT (160 nM)>DeltaG (170 nM)>DeltaA (250 nM)>CC (720 nM)>AT (950 nM). This order is comparable to the previous results of the gel mobility shift assay. Thus, this method can be a simple, useful tool for elucidating the mechanism of DNA mismatch repair as well as a novel probe for detecting of genetic mutation. 相似文献
124.
Black LA Nersesian DL Sharma P Ku YY Bennani YL Marsh KC Miller TR Esbenshade TA Hancock AA Cowart M 《Bioorganic & medicinal chemistry letters》2007,17(5):1443-1446
4-[6-(2-Tertiaryaminoethyl)naphthalen-2-yl]benzonitriles are conformationally constrained histamine H3 receptor antagonists with high potency and selectivity. The analogs were designed around a naphthalene core, with the goal of enhancing lipophilicity and CNS penetration, as compared to a previously reported benzofuran series. The SAR of the tertiary amine moiety is similar to that reported for the benzofuran series, with analogs bearing a 2-methylpyrrolidine substituent possessing the greatest rat and human H3 receptor binding affinities. 相似文献
125.
126.
Nonsyndromic orofacial clefting (NS-OFC) is a common complex multifactorial trait with a considerable genetic component and a number of candidate genes suggested by various approaches. Twenty biallelic and microsatellite DNA markers in the strong candidate loci TGFA, TGFB3, GABRB3, RARA, and BCL3 were analysed for allelic association with the NS-OFC phenotype in 112 nuclear families (proband + both parents) from Lithuania by using the transmission disequilibrium test (TDT). Associations were found between the TGFA gene marker rs2166975 and nonsyndromic cleft palate only (CPO) phenotype (p = 0.045, df 1) as well as between the D2S292 marker and the cleft lip with or without cleft palate (CL/CP) phenotype in allele-wise TDT (P = 0.005, df 9) and genotype-wise TDT (P = 0.021, df 24). A weak association (P = 0.085, df 3) of the BCL3 marker (BCL3 gene) with the risk of CPO was also found. Thus our initial results support the contribution of allelic variation in the TGFA locus to the aetiology of CL/CP in the population of Lithuania but they do not point to TGFA as a major causal gene. Different roles of the TGFA and BCL3 genes in the susceptibility to NS-OFC phenotypes are suggested. 相似文献
127.
Kim JD Kang SM Park MY Jung TY Choi HY Ku SK 《Bioscience, biotechnology, and biochemistry》2007,71(6):1527-1534
The preventive anti-diabetic effect of dangnyosoko (DNSK), a Chinese herbal medicine, was evaluated in STZ-induced diabetic rats. DNSK was orally administered once a day from 3 d after STZ-induction at 100, 200, and 500 mg/kg for 4 weeks, and the results were compared to those for glibenclamide. Dramatic decreases in body weight and plasma insulin levels and increases in blood and urine glucose levels were detected in STZ-induced diabetic animals with disruption and disappearance of pancreatic islets and increases in glucagon- and decreases in insulin-producing cells. However, these diabetic changes were significantly and dose-dependently inhibited by treatment with DNSK, and DNSK at 100 mg/kg showed more favorable effects than glibenclamide at 5 mg/kg. Based on these results, it is thought that DNSK has favorable effects in ameliorating changes in blood and urine glucose levels and body weight, and that histopathological changes in the pancreas in STZ induce diabetes. 相似文献
128.
Kuşçu Gökçe Ceren Gürel Çevik Buhur Aylin Oltulu Fatih Akman Levent Köse Timur Yavaşoğlu Nefise Ülkü Karabay Yavaşoğlu Altuğ 《Molecular biology reports》2022,49(3):1721-1729
Molecular Biology Reports - Polycystic ovary syndrome (PCOS) is a metabolic disease that causes infertility due to anovulation in women in reproductive age. It is known that clomiphene citrate (CC)... 相似文献
129.
Piotr Szweda Katarzyna Gucwa Ewelina Kurzyk Ewa Romanowska Katarzyna Dzier?anowska-Fangrat Anna Zielińska Jurek Piotr Marek Ku? S?awomir Milewski 《Indian journal of microbiology》2015,55(2):175-183
Development of effective and safe therapeutic treatment of fungal infections remains one of the major challenge for modern medicine. The aim of presented investigation was to analyze the in vitro antifungal activity of selected essential oils, ethanolic extracts of propolis and silver nanoparticles dropped on TiO2 against azole-resistant C. albicans (n = 20), C. glabrata (n = 14) and C. krusei (n = 10) clinical isolates. Among tested essential oils, the highest activity has definitely been found in the case of the oil isolated from the bark of Cinnamomum cassia, with MIC and MFC values for all tested strains in the range of 0.0006–0.0097 % (v/v) and 0.0012–0.019 % (v/v), respectively. High activity was also observed for the Lemon, Basil, Thyme, Geranium and Clove (from buds) essential oils. Significant differences in fungicidal activity have been observed in the case of four tested propolis samples. Only one of them revealed high activity, with MFC values in the range from 0.156 to 1.25 % (v/v). Satisfactory fungicidal activity, against C. albicans and C. glabrata isolates, was also observed in the case of silver nanoparticles, however C. krusei isolates were mostly resistant. We also revealed that constituents of most of essential oils and propolis as well as silver nanoparticles are not substrates for drug transporters, which belong to the most important factors affecting resistance of Candida spp. clinical isolates to many of conventional antimycotics. To conclude, the results of our investigation revealed that essential oils, propolis and silver nanoparticles represent high potential for controlling and prevention candidiasis. 相似文献
130.
Day length is an important environmental factor affecting the growth and development of maize (Zea mays), a short day (SD) plant grown in different latitudes. Leaf has been recognized as the light perceiving and signal producing organ. Under long day (LD) conditions, photoperiod-sensitive induction phase in maize begins at the fourth fully expanded leaf stage. However, the changes of maize leaf proteome in response to LD are largely unknown. To reveal maize proteome response to LD, proteins extracted from newly expanded fifth, sixth and seventh leaves from maize inbred line 496-10 (photoperiod sensitive) and Huangzao4 (HZ4, photoperiod insensitive) under LD treatments were compared via gel-based proteomic approach. As a result, eleven differentially expressed proteins were identified between 496-10 and HZ4 by mass spectrometry. This difference in protein accumulation was highly reproducible during the fifth to seventh leaf stages and most obvious at the seventh leaf stage. The identified proteins are mainly involved in circadian clock or iron metabolism, light harvesting and photosynthesis, nucleic acid metabolism and carbon fixation or energy metabolism. This study provides new insight into the influences of LD treatment on SD plants, such as maize, at proteome level. 相似文献