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31.
32.
Takeuchi H Fujiyuki T Shirai K Matsuo Y Kamikouchi A Fujinawa Y Kato A Tsujimoto A Kubo T 《FEBS letters》2002,513(2-3):230-234
To clarify the molecular basis underlying the neural function of the honeybee mushroom bodies (MBs), we identified three genes preferentially expressed in MB using cDNA microarrays containing 480 differential display-positive candidate cDNAs expressed locally or differentially, dependent on caste/aggressive behavior in the honeybee brain. One of the cDNAs encodes a putative type I inositol 1,4,5-trisphosphate (IP(3)) 5-phosphatase and was expressed preferentially in one of two types of intrinsic MB neurons, the large-type Kenyon cells, suggesting that IP(3)-mediated Ca(2+) signaling is enhanced in these neurons. 相似文献
33.
34.
Yukari Suzuki Michiko Minami Miho Suzuki Keiko Abe Shuhei Zenno Masafumi Tsujimoto Ken Matsumoto Yasufumi Minami 《The Journal of biological chemistry》2009,284(51):35597-35604
The eukaryotic translation initiation factor eIF4E plays a critical role in the control of translation initiation through binding to the mRNA 5′ cap structure. eIF4E is also a component of processing bodies and stress granules, which are two types of cytoplasmic RNA granule in which translationally inactivated mRNAs accumulate. We found that treatment with the Hsp90 inhibitor geldanamycin leads to a substantial reduction in the number of HeLa cells that contain processing bodies. In contrast, stress granules are not disrupted but seem to be only partially affected by the inhibition of Hsp90. However, it is striking that eIF4E as well as its binding partner eIF4E transporter (4E-T), which mediates the import of eIF4E into the nucleus, are obviously lost from stress granules. Furthermore, the amount of eIF4G that is associated with the cap via eIF4E is reduced by geldanamycin treatment. Thus, the chaperone activity of Hsp90 probably contributes to the correct localization of eIF4E and 4E-T to stress granules and also to the interaction between eIF4E and eIF4G, both of which may be needed for eIF4E to acquire the physiological functionality that underlies the mechanism of translation initiation. 相似文献
35.
Objective
Low-carbohydrate diets and their combination with high-protein diets have been gaining widespread popularity to control weight. In addition to weight loss, they may have favorable short-term effects on the risk factors of cardiovascular disease (CVD). Our objective was to elucidate their long-term effects on mortality and CVD incidence.Data sources
MEDLINE, EMBASE, ISI Web of Science, Cochrane Library, and ClinicalTrials.gov for relevant articles published as of September 2012. Cohort studies of at least one year’s follow-up period were included.Review methods
Identified articles were systematically reviewed and those with pertinent data were selected for meta-analysis. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) for all-cause mortality, CVD mortality and CVD incidence were calculated using the random-effects model with inverse-variance weighting.Results
We included 17 studies for a systematic review, followed by a meta-analysis using pertinent data. Of the 272,216 people in 4 cohort studies using the low-carbohydrate score, 15,981 (5.9%) cases of death from all-cause were reported. The risk of all-cause mortality among those with high low-carbohydrate score was significantly elevated: the pooled RR (95% CI) was 1.31 (1.07–1.59). A total of 3,214 (1.3%) cases of CVD death among 249,272 subjects in 3 cohort studies and 5,081 (2.3%) incident CVD cases among 220,691 people in different 4 cohort studies were reported. The risks of CVD mortality and incidence were not statistically increased: the pooled RRs (95% CIs) were 1.10 (0.98–1.24) and 0.98 (0.78–1.24), respectively. Analyses using low-carbohydrate/high-protein score yielded similar results.Conclusion
Low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality and they were not significantly associated with a risk of CVD mortality and incidence. However, this analysis is based on limited observational studies and large-scale trials on the complex interactions between low-carbohydrate diets and long-term outcomes are needed. 相似文献36.
Larson SR Kishii M Tsujimoto H Qi L Chen P Lazo GR Jensen KB Wang RR 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(1):189-206
Allotetraploid (2n = 4x = 28) Leymus triticoides and Leymus cinereus are divergent perennial grasses, which form fertile hybrids. Genetic maps with n = 14 linkage groups (LG) comprised with 1,583 AFLP and 67 heterologous anchor markers were previously used for mapping quantitative
trait loci (QTLs) in these hybrids, and chromosomes of other Leymus wildryes have been transferred to wheat. However, identifications of the x = 7 homoeologous groups were tenuous and genetic research has been encumbered by a lack of functional, conserved gene marker
sequences. Herein, we mapped 350 simple sequence repeats and 26 putative lignin biosynthesis genes from a new Leymus EST library and constructed one integrated consensus map with 799 markers, including 375 AFLPs and 48 heterologous markers,
spanning 2,381 centiMorgans. LG1b and LG6b were reassigned as LG6b* and LG1b*, respectively, and LG4Ns and LG4Xm were inverted so that all 14 linkage groups are aligned to the x = 7 Triticeae chromosomes based on EST alignments to barley and other reference genomes. Amplification of 146 mapped Leymus ESTs representing six of the seven homoeologous groups was shown for 17 wheat-Leymus chromosome introgression lines. Reciprocal translocations between 4L and 5L in both Leymus and Triticum monococcum were aligned to the same regions of Brachypodium chromosome 1. A caffeic acid O-methyltransferase locus aligned to fiber QTL peaks on Leymus LG7a and brown midrib mutations of maize and sorghum. Glaucousness genes on Leymus and wheat chromosome 2 were aligned to the same region of Brachypodium chromosome 5. Markers linked to the S self-incompatibility gene on Leymus LG1a cosegregated with markers on LG2b, possibly cross-linked by gametophytic selection. Homoeologous chromosomes 1 and 2
harbor the S and Z gametophytic self-incompatibility genes of Phalaris, Secale, and Lolium, but the Leymus chromosome-2 self-incompatibility gene aligns to a different region on Brachypodium chromosome 5. Nevertheless, cosegregation of self-incompatibility genes on Leymus presents a powerful system for mapping these loci. 相似文献
37.
Saktrakulkla P Toriumi S Tsujimoto M Patarapanich C Suwanborirux K Saito N 《Bioorganic & medicinal chemistry》2011,19(15):4421-4436
A three-step transformation of ecteinascidin 770 (1b) into 2'-N-indole-3-carbonyl derivative 3 via 18,6'-O-bisallyl-protected derivative 4a, which was shown to have higher cytotoxicity than 1b, is presented. In addition, a number of 2'-N amide derivatives of 1b have been prepared from 4a and their in vitro cytotoxicity were determined by measuring IC?? values against human cell lines HCT116, QG56, and DU145. Benzoyl amide derivatives 7a-c showed similar in vitro cytotoxicity to 1b, whereas the nitrogen-containing heterocyclic derivatives 7d-h and cinnamoyl derivatives 9a-b showed higher cytotoxicity than 1b. In contrast, the 18,6'-O-bisallyl protected derivatives 4a-c, 6a-h, and 8a-b showed dramatic decreases in cytotoxicity relative to 1b. 相似文献
38.
Induction of cytochrome P450 1A is required for circulation failure and edema by 2,3,7,8-tetrachlorodibenzo-p-dioxin in zebrafish 总被引:1,自引:0,他引:1
Teraoka H Dong W Tsujimoto Y Iwasa H Endoh D Ueno N Stegeman JJ Peterson RE Hiraga T 《Biochemical and biophysical research communications》2003,304(2):223-228
The mechanism of toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is thought to result from changes in gene expression via the aryl hydrocarbon receptor (AHR). The induction of cytochrome P450 1A (CYP1A) in various organs is a cardinal effect of TCDD. However, whether CYP1A is involved in endpoints of TCDD toxicity is controversial. We investigated the role of CYP1A in TCDD-induced developmental toxicities using gene knock-down with morpholino antisense oligos. Exposure of zebrafish embryos to TCDD, at concentrations eliciting the hallmark endpoints of developmental toxicity, induced CYP1A in the heart and vascular endothelium throughout the body. This induction by TCDD was markedly inhibited by morpholinos to zebrafish arylhydrocarbon receptor 2 (zfAHR2-MO) and to zebrafish CYP1A (zfCYP1A-MO). The zfAHR2-MO but not the zfCYP1A-MO inhibited zfCYP1A mRNA expression, indicating the specificities of these morpholinos. Injection of either zfAHR2-MO or zfCYP1A-MO blocked the representative signs of TCDD developmental toxicity in zebrafish, pericardial edema and trunk circulation failure. The morpholinos appeared do not affect normal development in TCDD-untreated embryos. These results suggest a mediatory role of zfCYP1A induction through zfAHR2 activation in causing circulation failure by TCDD in zebrafish. This is the first molecular evidence demonstrating an essential requirement for CYP1A induction in TCDD-evoked developmental toxicities in any vertebrate species. 相似文献
39.
Molecular monitoring of bleomycin-induced pulmonary fibrosis by cDNA microarray-based gene expression profiling. 总被引:5,自引:0,他引:5
S Katsuma K Nishi K Tanigawara H Ikawa S Shiojima K Takagaki Y Kaminishi Y Suzuki A Hirasawa T Ohgi J Yano Y Murakami G Tsujimoto 《Biochemical and biophysical research communications》2001,288(4):747-751
Pulmonary fibrosis is a progressive disorder whose molecular pathology is poorly understood. Here we developed an in-house cDNA microarray ("lung chip") originating from a lung-normalized cDNA library. By using this lung chip, we analyzed global gene expression in a murine model of bleomycin-induced fibrosis and selected 82 genes that differed by more than twofold intensity in at least one pairwise comparison with controls. Cluster analysis of these selected genes showed that the expression of genes associated with inflammation reached maximum levels at 5 days after bleomycin administration, while genes involved in the development of fibrosis increased gradually up to 14 days after bleomycin treatment. These changes in gene expression signature were well correlated with observed histopathological changes. The results show that microarray analysis of animal disease models is a powerful approach to understanding the gene expression programs that underlie these disorders. 相似文献
40.
Wheat (Triticum aestivum L.) haploids were produced by crossing with Job's tears (Coix lachryma-jobi L.) as the pollen parent. Pollination was followed by 2,4-D treatment, detached tiller culture, and embryo culture, as described for maize pollination. The frequency of embryo formation was similar to that obtained by crossing wheat with maize pollen. Job's tears is a perennial plant which forms several stalks and its pollen can be collected throughout the year when the plant is maintained in a controlled environment. Our results indicate that Job's tears can be used as the pollen parent for wheat crosses for haploid production without requiring synchronization of flowering dates. 相似文献