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111.
112.
Yosuke Hiramuki Takahiko Sato Yasuhide Furuta M. Azim Surani Atsuko Sehara-Fujisawa 《PloS one》2015,10(6)
When skeletal muscle fibers are injured, they regenerate and grow until their sizes are adjusted to surrounding muscle fibers and other relevant organs. In this study, we examined whether Mest, one of paternally expressed imprinted genes that regulates body size during development, and miR-335 located in the second intron of the Mest gene play roles in muscle regeneration. We generated miR-335-deficient mice, and found that miR-335 is a paternally expressed imprinted microRNA. Although both Mest and miR-335 are highly expressed during muscle development and regeneration, only Mest+/- (maternal/paternal) mice show retardation of body growth. In addition to reduced body weight in Mest+/-; DMD-null mice, decreased muscle growth was observed in Mest+/- mice during cardiotoxin-induced regeneration, suggesting roles of Mest in muscle regeneration. Moreover, expressions of H19 and Igf2r, maternally expressed imprinted genes were affected in tibialis anterior muscle of Mest+/-; DMD-null mice compared to DMD-null mice. Thus, Mest likely mediates muscle regeneration through regulation of imprinted gene networks in skeletal muscle. 相似文献
113.
Eiichiro Ono Yu Homma Manabu Horikawa Satoshi Kunikane-Doi Haruna Imai Seiji Takahashi Yosuke Kawai Masaji Ishiguro Yuko Fukui Toru Nakayama 《The Plant cell》2010,22(8):2856-2871
We identified two glycosyltransferases that contribute to the structural diversification of flavonol glycosides in grapevine (Vitis vinifera): glycosyltransferase 5 (Vv GT5) and Vv GT6. Biochemical analyses showed that Vv GT5 is a UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase (GAT), and Vv GT6 is a bifunctional UDP-glucose/UDP-galactose:flavonol-3-O-glucosyltransferase/galactosyltransferase. The Vv GT5 and Vv GT6 genes have very high sequence similarity (91%) and are located in tandem on chromosome 11, suggesting that one of these genes arose from the other by gene duplication. Both of these enzymes were expressed in accordance with flavonol synthase gene expression and flavonoid distribution patterns in this plant, corroborating their significance in flavonol glycoside biosynthesis. The determinant of the specificity of Vv GT5 for UDP-glucuronic acid was found to be Arg-140, which corresponded to none of the determinants previously identified for other plant GATs in primary structures, providing another example of convergent evolution of plant GAT. We also analyzed the determinants of the sugar donor specificity of Vv GT6. Gln-373 and Pro-19 were found to play important roles in the bifunctional specificity of the enzyme. The results presented here suggest that the sugar donor specificities of these Vv GTs could be determined by a limited number of amino acid substitutions in the primary structures of protein duplicates, illustrating the plasticity of plant glycosyltransferases in acquiring new sugar donor specificities. 相似文献
114.
Functional and morphological responses of endothelial cells (ECs) to fluid shear stress are thought to be mediated by several mechanosensitive molecules. However, how the force due to fluid shear stress applied to the apical surface of ECs is transmitted to the mechanosensors is poorly understood. In the present paper, we performed an analysis of an intracellular mechanical field by observation of the deformation behaviors of living ECs exposed to shear stress with a novel experimental method. Lateral images of human umbilical vein ECs before and after the onset of flow were obtained by confocal microscopy, and image correlation and finite element analysis were performed for quantitative analyses of subcellular strain due to shear stress. The shear strain of the cells changed from 1.06 ± 1.09% (mean ± SD) to 4.67 ± 1.79% as the magnitude of the shear stress increased from 2 to 10 Pa. The nuclei of ECs also exhibited shear deformation, which was similar to that observed in cytoplasm, suggesting that nuclei transmit forces from apical to intracellular components, as well as cytoskeletons. The obtained strain-stress relation resulted in a mean shear modulus of 213 Pa for adherent ECs. These results provide a mechanical perspective on the investigation of flow-sensing mechanisms of ECs. 相似文献
115.
Yosuke Ichijima Ken-ichi Yoshioka Yoshiko Yoshioka Keitaro Shinohe Hiroaki Fujimori Junya Unno Masatoshi Takagi Hidemasa Goto Masaki Inagaki Shuki Mizutani Hirobumi Teraoka 《PloS one》2010,5(1)
During tumorigenesis, cells acquire immortality in association with the
development of genomic instability. However, it is still elusive how genomic
instability spontaneously generates during the process of tumorigenesis. Here,
we show that precancerous DNA lesions induced by oncogene acceleration, which
induce situations identical to the initial stages of cancer development, trigger
tetraploidy/aneuploidy generation in association with mitotic aberration.
Although oncogene acceleration primarily induces DNA replication stress and the
resulting lesions in the S phase, these lesions are carried over into the M
phase and cause cytokinesis failure and genomic instability. Unlike directly
induced DNA double-strand breaks, DNA replication stress-associated lesions are
cryptogenic and pass through cell-cycle checkpoints due to limited and
ineffective activation of checkpoint factors. Furthermore, since damaged M-phase
cells still progress in mitotic steps, these cells result in chromosomal
mis-segregation, cytokinesis failure and the resulting tetraploidy generation.
Thus, our results reveal a process of genomic instability generation triggered
by precancerous DNA replication stress. 相似文献
116.
Noriko Kohyama Makiko Chono Hiroyuki Nakagawa Yosuke Matsuo Hiroshi Ono Hitoshi Matsunaka 《Bioscience, biotechnology, and biochemistry》2017,81(11):2112-2118
In red wheat, reddish-brown pigments accumulate in testa of mature seeds. Half-cut wheat seeds were immersed in p-dimethylaminocinnamaldehyde (DMACA) reagent that stains flavanol structures blue. Testa of 10–40 days after flowering (DAF) in red wheat (“Norin 61” and “Satonosora”) seeds were stained blue and the reagent color changed to blue with 10–25 DAF seeds. No blue staining was observed in white wheat (“Tamaizumi”) seeds during maturation. “Norin 61” seed coats at 10 DAF contained dihydroquercetin, dihydromyricetin, (+)-catechin, procyanidin B3, and prodelphinidin B3, which were identified by HPLC-diode array detector and LC-MS/MS analyses. These five components began accumulating 7 DAF, reached maxima at 10 or 15 DAF, and then decreased in red wheat seeds, but were not detected in white wheat seeds. These results suggest that flavanol and proanthocyanidins are possible precursors of the reddish-brown pigments of red wheat seeds, and are converted to insoluble compounds as the seeds mature. 相似文献
117.
Sekine Y Furuya Y Nishii M Koike H Matsui H Suzuki K 《Biochemical and biophysical research communications》2008,372(2):356-361
Recently, statins have been being studied for their proapoptic and antimetastatic effects. However, the exact mechanisms of their anticancer action are still unclear. Dolichyl phosphate is a nonsterol isoprenoid derivative in the mevalonate pathway that affects the expression of the Insulin-like growth factor 1 receptor (IGF-1R). IGF-1R activation is required for prostate cell proliferation; therefore, IGF-1R inhibitory agents may be of preventive and/or therapeutic value. In this study, the effects of simvastatin on IGF-1R signaling in prostate cancer PC-3 cells were examined. Simvastatin suppressed proliferation and induced apoptosis of PC-3, and the expression of IGF-1R was suppressed by simvastatin. Knockdown of IGF-1R by siRNA led to inhibition of proliferation of PC-3. Simvastatin also inhibited IGF-1-induced activation of both ERK and Akt signaling and IGF-1-induced PC-3 cell proliferation. Our results suggest statins are potent inhibitors of the IGF-1/IGF-1R system in prostate cancer cells and may be beneficial in prostate cancer treatment. 相似文献
118.
119.
Fumihiro Fujiki Yoshihiro Oka Mai Kawakatsu Akihiro Tsuboi Hiroko Nakajima Olga A. Elisseeva Yukie Harada Zheyu Li Naoko Tatsumi Eriko Kamino Toshiaki Shirakata Sumiyuki Nishida Yuki Taniguchi Ichiro Kawase Yusuke Oji Haruo Sugiyama 《Microbiology and immunology》2008,52(12):591-600
The Wilms' tumor gene WT1 is overexpressed in various tumors, and the WT1 protein has been demonstrated to be an attractive target antigen for cancer immunotherapy. A WT1 protein‐derived 16‐mer peptide, WT1332 (KRYFKLSHLQMHSRKH), which was naturally generated through processing in cells and could elicit Th1‐type CD4+ helper T cell responses with an HLA‐DRB1*0405‐restriction has previously been identified by us. In the present study, it has been demonstrated that WT1332 can induce WT1332‐specific CD4+ T cell responses with the restriction of not only HLA‐DRB1*0405 but also HLA‐DRB1*1501, ‐DRB1*1502, or ‐DPB1*0901. These HLA class II‐restricted WT1332‐specific CD4+ T cell lines produced IFN‐γ but neither IL‐4 nor IL‐10 with WT1332 stimulation, thus showing a Th1‐type cytokine profile. Furthermore, HLA‐DRB1*1501 or ‐DRB1*1502‐restricted WT1332‐specific CD4+ T cell lines responded to WT1‐expressing transformed cells in an HLA‐DRB1‐restricted manner, which is consistent with our previous finding that WT1332 is a naturally processed peptide. These results indicate that the natural peptide, WT1332, is a promiscuous WT1‐specific helper epitope. WT1332 is expected to apply to cancer patients with various types of HLA class II as a WT1‐specific helper peptide in combination with HLA class I‐restricted WT1 peptides. 相似文献
120.
Iwata H Uga Y Yoshioka Y Ebana K Hayashi T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(8):1437-1449
One way to use a crop germplasm collection directly to map QTLs without using line-crossing experiments is the whole genome
association mapping. A major problem with association mapping is the presence of population structure, which can lead to both
false positives and failure to detect genuine associations (i.e., false negatives). Particularly in highly selfing species
such as Asian cultivated rice, high levels of population structure are expected and therefore the efficiency of association
mapping remains almost unknown. Here, we propose an approach that combines a Bayesian method for mapping multiple QTLs with
a regression method that directly incorporates estimates of population structure. That is, the effects due to both multiple
QTLs and population structure were included in our statistical model. We evaluated the efficiency of our approach in simulated-
and real-trait analyses of a rice germplasm collection. Simulation analyses based on real marker data showed that our model
could suppress both false-positive and false-negative rates and the error of estimation of genetic effects over single QTL
models, indicating that our model has statistically desirable attributes over single QTL models. As real traits, we analyzed
the size and shape of milled rice grains and found significant markers that may be linked to QTLs reported previously. Association
mapping should have good prospects in highly selfing species such as rice if proper methods are adopted. Our approach will
be useful for the whole genome association mapping of various selfing crop species. 相似文献