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111.
Nicole YP Souren Pavlo Lutsik Gilles Gasparoni Sascha Tierling Jasmin Gries Matthias Riemenschneider Jean-Pierre Fryns Catherine Derom Maurice P Zeegers J?rn Walter 《Genome biology》2013,14(5):R44
Background
Low birth weight is associated with an increased adult metabolic disease risk. It is widely discussed that poor intra-uterine conditions could induce long-lasting epigenetic modifications, leading to systemic changes in regulation of metabolic genes. To address this, we acquire genome-wide DNA methylation profiles from saliva DNA in a unique cohort of 17 monozygotic monochorionic female twins very discordant for birth weight. We examine if adverse prenatal growth conditions experienced by the smaller co-twins lead to long-lasting DNA methylation changes.Results
Overall, co-twins show very similar genome-wide DNA methylation profiles. Since observed differences are almost exclusively caused by variable cellular composition, an original marker-based adjustment strategy was developed to eliminate such variation at affected CpGs. Among adjusted and unchanged CpGs 3,153 are differentially methylated between the heavy and light co-twins at nominal significance, of which 45 show sensible absolute mean β-value differences. Deep bisulfite sequencing of eight such loci reveals that differences remain in the range of technical variation, arguing against a reproducible biological effect. Analysis of methylation in repetitive elements using methylation-dependent primer extension assays also indicates no significant intra-pair differences.Conclusions
Severe intra-uterine growth differences observed within these monozygotic twins are not associated with long-lasting DNA methylation differences in cells composing saliva, detectable with up-to-date technologies. Additionally, our results indicate that uneven cell type composition can lead to spurious results and should be addressed in epigenomic studies. 相似文献112.
lysE24 is an allele of lysE encoding an L-lysine exporter of Corynebacterium glutamicum. The mutant gene is able to induce L-lysine production in Methylophilus methylotrophus. Although lysE24 has a mutation in the middle of lysE that results in chain termination, the entire lysE locus, including the region downstream of the short open reading frame, is necessary for L-lysine production. We propose that separate polypeptides are synthesized from the lysE24 locus due to reinitiation of translation utilizing an existing start codon beyond the site of the frameshift, and present evidence that translational coupling is required to form the functional lysE24 product. In addition, expression of lysE24 induces L-lysine production in another methylotroph, Methylobacillus glycogenes. These data suggest that the lysE24 product is a split protein and that this curious feature might be a structure necessary for its functioning in certain obligate gram-negative methylotrophs. 相似文献
113.
114.
Irie O Ehara T Iwasaki A Yokokawa F Sakaki J Hirao H Kanazawa T Teno N Horiuchi M Umemura I Gunji H Masuya K Hitomi Y Iwasaki G Nonomura K Tanabe K Fukaya H Kosaka T Snell CR Hallett A 《Bioorganic & medicinal chemistry letters》2008,18(14):3959-3962
Nonpeptidic, selective, and potent cathepsin S inhibitors were derived from an in-house pyrrolopyrimidine cathepsin K inhibitor by modification of the P2 and P3 moieties. The pyrrolopyrimidine-based inhibitors show nanomolar inhibition of cathepsin S with over 100-fold selectivity against other cysteine proteases, including cathepsin K and L. Some of the inhibitors showed cellular activities in mouse splenocytes as well as oral bioavailabilities in rats. 相似文献
115.
116.
There are several studies that estimate the emergent event from the time series of behavior in some organisms. However, they do not focus on the emergent event itself. Our aim is to detect the emergent event from the time series of individual's behavior, focusing on the transition from predictable machinery behavior to purpose-oriented behavior and vice versa. We recorded the behavior of larvae and adults of black larder beetle. To detect the emergent event of the beetle, we defined a forward- and backward-prediction model. In the forward-prediction, the next state in the time series of behavior was interpreted by precedent behavior. In the backward-prediction, the previous state in the time series of behavior was interpreted by subsequent behavior. The time step with conspicuous peak of the co-intensity of errors in the forward- and backward-prediction was regarded as the timing at which the emergent event occurs. At the same time, the time series of states was estimated to determine whether noise was stationary or non-stationary. The attribute of noise was estimated using the Allan variance. The time series of the larvae's velocity of walking showed stationary noise. But in the case of the adults, whole time series contained 1/f noise. And, when time series was divided before and after the detected event, the noise changed from stationary to non-stationary and vice versa. These results suggest that development enables an individual to change the internal mechanism of walk considering the slight change of environment. 相似文献
117.
Suzuki Y Igawa S Torikoshi S Gunji A 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2001,8(1):P77-P78
Researchers examined the relationship between changes in physiological function in space and aging in older females. The hypotheses were that some of the changes may be due to a decrease in gravitational stimulation, but that some could be caused by aging itself. Data are based on a mixed longitudinal research study performed in aged females since 1995. 相似文献
118.
Yukihiro Kitade Shohei Okino Wataru Gunji Kazumi Hiraga Masako Suda Nobuaki Suzuki Masayuki Inui Hideaki Yukawa 《Applied microbiology and biotechnology》2013,97(18):8219-8226
Expression plasmids that facilitate production of bio-based products are susceptible to toxic effects that frequently affect plasmid structural stability in recombinant microbial cells. In order to enhance plasmid stability in recombinant Corynebacterium glutamicum, an expression plasmid containing genes of the Clostridium acetobutylicum butyryl-CoA synthesis operon with high structural instability within wild-type C. glutamicum was employed. From a total of 133 mutants exhibiting disruptions in 265 suspect genes, only cgR_0322-deficient mutant was able to maintain the expression plasmid intact. The mutant exhibited normal growth under standard laboratory conditions but its transformation efficiency was about one order of magnitude lower than that of wild-type strain. The cgR_0322 gene encodes an endonuclease that is active against single- as well as double-stranded DNA substrates in the presence of Mg2+. The cgR_0322-deficient strain should therefore facilitate the development of more robust C. glutamicum strains to be used as microbial production hosts. 相似文献
119.
We propose a dialogue-based society model which explains how the transitive law of the causality is originated. Causality is, in general, formalized by using axiomatic approaches. Instead of using axiomatic methods, we, however, compose a model consisting of agents who have knowledge about causal relations among objects. The model society can reveal the transitive law through interactional dialogues among themselves. The agents are reciprocally influenced, if they have either completely same opinions, or a particular pattern of opinions, that are regarded as the extension of such exact accordance. In addition, we add some vagueness to the dialogue, which is closer to a real communication than the former model. A set of knowledge of each agent is expressed as a directed graph, hence the every model can be construed as mere transformations of directed graphs through the interactions among directed graphs themselves. Following this perspective, the models are the systems that connect local logic with global one, while the union of the directed graphs is regarded as the global. 相似文献
120.
Tomoko Yamazaki Mayumi Mori Satoko Arai Ryosuke Tateishi Masanori Abe Mihoko Ban Akemi Nishijima Maki Maeda Takeharu Asano Toshihiro Kai Kiyohiro Izumino Jun Takahashi Kayo Aoyama Sei Harada Toru Takebayashi Toshiaki Gunji Shin Ohnishi Shinji Seto Yukio Yoshida Yoichi Hiasa Kazuhiko Koike Ken-ichi Yamamura Ken-ichiro Inoue Toru Miyazaki 《PloS one》2014,9(10)