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121.
Chan T Kondow A Hosoya A Hitachi K Yukita A Okabayashi K Nakamura H Ozawa H Kiyonari H Michiue T Ito Y Asashima M 《FEBS letters》2007,581(14):2691-2696
122.
The tiger pufferfish (fugu), Takifugu rubripes, is a model fish that has had its genome entirely sequenced. By performing genomewide linkage analyses, we show that the sex of fugu is determined by a single chromosomal region on linkage group 19 in an XX-XY system. 相似文献
123.
Synergism of accessory factors in functional expression of mammalian odorant receptors 总被引:1,自引:0,他引:1
The discovery of odorant receptors led to endeavors in matching them with their cognate ligands. Although it has been challenging to functionally express odorant receptors in heterologous cells, previous studies have linked efficient odorant receptor expression with N-terminal modifications and accessory proteins, including the receptor-transporting proteins (RTPs) and Ric8b. Here we have shown that a shorter form of RTP1, RTP1S, supports robust cell-surface and functional expression of representative odorant receptors. Using a combination of accessory proteins, including RTP1S, Ric8b, and G(alphaolf), a diverse set of untagged odorant receptors were successfully expressed heterologously due to the synergistic effects among the various accessory proteins. Furthermore, the addition of an N-terminal rhodopsin tag to the odorant receptors, along with the same set of accessory proteins, exhibits an additional level of synergism, inducing enhanced odorant receptor responses to odorants and thus defining a more efficient heterologous expression system. We then showed that the presence or absence of different N-terminal tags has little effect on the ligand specificity of odorant receptors, although the amount of receptor expressed can play a role in the ligand response profile. The accuracy of the odorant receptor heterologous expression system involving tagged odorant receptors and various accessory proteins promises success in high throughput de-orphaning of mammalian odorant receptors. 相似文献
124.
125.
M. Abdul Maleque Hiroaki T. Ishii Kaoru Maeto Shingo Taniguchi 《Arthropod-Plant Interactions》2007,1(3):175-185
We evaluated the effectiveness of line thinning, a new silvicultural technique, toward restoring diversity of Coleoptera in
overstocked Cryptomeria japonica D. Don plantations in central Japan. We compared the abundance of some common Coleoptera families between line-thinned stands
and adjacent unthinned stands in two plantations: low-elevation Sugi site (4 years since thinning) and high-elevation Kuchiotani
site (6 years since thinning). Many bettle families comprising various functional groups such as plant feeders, wood borers,
rotten wood feeders, root feeders, fungus feeders, dung feeders, and scavengers were more abundant in the line-thinned stands
than in the unthinned stands. Furthermore, some important families were missing from the unthinned stands. There were strong
positive relationships between Coleopteran abundance and understory vegetation. Our results suggest that line thinning may
potentially increase biodiversity in overstocked C. japonica plantations by restoring important ecological processes such as food-web interactions (pollination, predation, herbivory,
decomposition, parasitism, etc.), and habitat conditions. 相似文献
126.
Cooke PS Holsberger DR Cimafranca MA Meling DD Beals CM Nakayama K Nakayama KI Kiyokawa H 《Obesity (Silver Spring, Md.)》2007,15(6):1400-1408
Objective: The etiology of some obesity may involve adipocyte hyperplasia. However, the role of adipocyte number in establishing adipose mass is unclear. Cyclin‐dependent kinase inhibitor p27 regulates activity of cyclin/cyclin‐dependent kinase complexes responsible for cell cycle progression. This protein is critical for establishing adult adipocyte number, and p27 knockout increases adult adipocyte number. The SCF (for Skp1‐Cullin‐F‐box protein) complex targets proteins such as p27 for ubiquitin‐proteosome degradation; the F box protein S phase kinase‐associated protein 2 (Skp2), a component of the SCF complex, specifically recognizes p27 for degradation. We used Skp2 knockout (Skp2?/?) mice to test whether Skp2 loss decreased adipose mass and adipocyte number. Research Methods and Procedures: We measured body weight, adipose mass, adipocyte diameter and number, and glucose tolerance in wild‐type (WT), Skp2?/?, and p27?/?Skp2?/? mice. Mouse embryo fibroblasts (MEFs) from WT and Skp2?/? fetuses were differentiated to determine whether Skp2 directly affected adipogenesis. Results: Skp2?/? mice had a 50% decrease in both subcutaneous and visceral fat pad mass and adipocyte number; these decreases exceeded those in body weight, kidney, or muscle. To test the hypothesis that Skp2 effects on adipocyte number involved p27 accumulation, we used p27?/?Skp2?/? double knockout mice. The Skp2?/? decrements in adipocyte number and fat pad mass were totally reversed in p27?/?Skp2?/? mice. Adipogenesis was inhibited in MEFs from Skp2?/? vs. WT mice, and this inhibition was absent in MEFs from p27?/?Skp2?/? mice. Discussion: Our results indicate that Skp2 regulates adipogenesis and ultimate adipocyte number in vivo; thus, Skp2 may contribute to obesity involving adipocyte hyperplasia. 相似文献
127.
Michinori Tanaka Shinya Oishi Hiroaki Ohno Nobutaka Fujii 《International journal of peptide research and therapeutics》2007,13(1-2):271-279
A reliable method for solid-phase synthesis of peptide aldehydes by using a new oxazolidine linker is described. Based on
a comparative study using the usual cleavage protocol as is used for the Fmoc-based peptide synthesis, we found that this
new linker is more appropriate for the synthesis of peptide aldehydes compared with the precedent acetal, semicarbazone or
threonine linker. Whereas N-Acylated oxazolidines might be partially deprotected to non-N-acylated intermediates in the TFA cocktail containing several soft nucleophiles which cause significant side reactions, the
new oxazolidine linker could produce the desired peptide aldehydes by simple Et2O washing and subsequent aqueous workup in high chemical yields and purity. We demonstrate the new method is useful especially
for the preparation of highly functionalized long-chain peptide aldehydes which require several scavenger chemicals in the
final deprotection step.
This paper is dedicated to the memory of the late Prof. R. Bruce Merrifield, who passed away May 14, 2006. 相似文献
128.
Applicability of a segmental bioelectrical impedance analysis for predicting the whole body skeletal muscle volume. 总被引:1,自引:0,他引:1
Noriko I Tanaka Masae Miyatani Yoshihisa Masuo Tetsuo Fukunaga Hiroaki Kanehisa 《Journal of applied physiology》2007,103(5):1688-1695
This study aimed to test the hypothesis that a segmental bioelectrical impedance (BI) analysis can predict whole body skeletal muscle (SM) volume more accurately than a whole body BI analysis. Thirty males (19-34 yr) participated in this study. They were divided into validation (n = 20) and cross-validation groups (n = 10). The BI values were obtained using two methods: whole body BI analysis, which determines impedance between the wrist and ankle; and segmental BI analysis, which determines the impedance of every body segment in both sides of the upper arm, lower arm, upper leg and lower leg, and five parts of the trunk. Using a magnetic resonance imaging method, whole body SM volume was determined as a reference (SMV(MRI)). Simple and multiple regression analyses were applied to (length)(2)/Z (BI index) for the whole body and for every body segment, respectively, to develop the prediction equations of SMV(MRI). In the validation group, there were no significant differences between the measured and estimated SMV and no systematic errors in either BI analysis. In the cross-validation group, the whole body BI analysis produced systematic errors and resulted in the overestimation of SMV(MRI), but the segmental BI analysis was cross-validated. In the pooled data, the segmental BI analysis produced a prediction equation, which involves the BI indexes of the trunk and upper thigh as independent variables, with a SE of estimation of 1,693.8 cm(3) (6.1%). Thus the findings obtained here indicated that the segmental BI analysis is superior to the whole body BI analysis for estimating SMV(MRI). 相似文献
129.
130.
Akihiro Kuno Yoshihisa Ikeda Shinya Ayabe Kanako Kato Kotaro Sakamoto Sayaka R. Suzuki Kento Morimoto Arata Wakimoto Natsuki Mikami Miyuki Ishida Natsumi Iki Yuko Hamada Megumi Takemura Yoko Daitoku Yoko Tanimoto Tra Thi Huong Dinh Kazuya Murata Michito Hamada Masafumi Muratani Atsushi Yoshiki Fumihiro Sugiyama Satoru Takahashi Seiya Mizuno 《PLoS biology》2022,20(1)
Genome editing can introduce designed mutations into a target genomic site. Recent research has revealed that it can also induce various unintended events such as structural variations, small indels, and substitutions at, and in some cases, away from the target site. These rearrangements may result in confounding phenotypes in biomedical research samples and cause a concern in clinical or agricultural applications. However, current genotyping methods do not allow a comprehensive analysis of diverse mutations for phasing and mosaic variant detection. Here, we developed a genotyping method with an on-target site analysis software named Determine Allele mutations and Judge Intended genotype by Nanopore sequencer (DAJIN) that can automatically identify and classify both intended and unintended diverse mutations, including point mutations, deletions, inversions, and cis double knock-in at single-nucleotide resolution. Our approach with DAJIN can handle approximately 100 samples under different editing conditions in a single run. With its high versatility, scalability, and convenience, DAJIN-assisted multiplex genotyping may become a new standard for validating genome editing outcomes.Genome editing can introduce designed mutations into a target genomic site, but also into unintended off-target sites. DAJIN, a novel nanopore sequencing data analysis tool, identifies and quantifies allele numbers and their mutation patterns, reporting consensus sequences and visualizing mutations in alleles at single-nucleotide resolution. 相似文献