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951.
952.
There has been no structural information about the core protein of salmon nasal cartilage proteoglycan although its physiological activities have been investigated. Internal amino acid sequencing using nano-LC/MS/MS revealed that the salmon proteoglycan was aggrecan. Primer walk sequencing based on the amino acid information determined that the salmon aggrecan cDNA is comprised of 4207 bp nucleotides predicted to encode 1324 amino acids with a molecular mass of 143,276. It exhibited significant similarities to predicted pufferfish aggrecan, zebrafish similar to aggrecan, zebrafish aggrecan, bovine aggrecan and human aggrecan isoform 2 precursor; whose amino acid identities were 56%, 55%, 49%, 31% and 30%, respectively. Salmon cartilage aggrecan had globular domains G1, G2 and G3 as in mammalian aggrecans. Neither the putative keratan sulfate attachment domain enriched with serine, glutamic acid and proline, nor the putative chondroitin sulfate attachment domain with repeating amino acid sequence containing serine–glycine, found in mammalian aggrecans were observed in salmon, however, random serine–glycine (or glycine–serine) sequences predicted to the sugar chain attachment sites were observed. Based on cDNA analysis and amino acid analysis after β-elimination, the ratio of serine attached to sugar chains was calculated to be approximately 37.7% of total serine, that is, 46 of 123 serine residues. 相似文献
953.
Chisato Fujimoto Yoshiro Ishimaru Yuka Katano Takumi Misaka Tatsuya Yamasoba Tomiko Asakura Keiko Abe 《Biochemical and biophysical research communications》2011,404(4):497
The polycystic kidney disease 1-like 3 (PKD1L3)–polycystic kidney disease 2-like 1 (PKD2L1) complex functions as a Ca2+-permeable, non-selective cation channel that is activated by acid and its subsequent removal; this is called an off-response. In this study, we identified a single aspartic residue in PKD2L1 that is responsible for the Ca2+ permeation of the PKD1L3/PKD2L1 complex. Calcium imaging analysis using point mutants of negatively charged amino acids present in the putative pore regions of PKD1L3 and PKD2L1 revealed that neutralization of the aspartic residue in PKD2L1 (D523N), which is conserved among PKD2 family members, abolished Ca2+ permeation, despite robust cell surface expression. In contrast, neutralization of the other negatively charged residues of PKD1L3 (D2049N and E2072Q) and PKD2L1 (D525N and D530N) as well as substitution of Asp523 with a glutamate residue (D523E) had little effect on Ca2+ permeation properties. These results demonstrate that Asp523 in PKD2L1 is a key determinant of Ca2+ permeation into the PKD1L3/PKD2L1 complex and that PKD2L1 contributes to forming the pore of the PKD1L3/PKD2L1 channel. 相似文献
954.
TMEM16E (GDD1) Exhibits Protein Instability and Distinct Characteristics in Chloride Channel/Pore Forming Ability 下载免费PDF全文
955.
Beak marks on butterfly wings have been used as an indicator of predation pressure. The relationship between butterflies and their predators in the field was examined to evaluate the beak mark rate as an indicator of predation pressure. Transect censuses were conducted to measure the beak mark rate on butterflies from May to November, 2010, in Shiga Prefecture, Japan. A total of 1216 butterflies of 42 species from five families were observed during the study period. The beak mark rate in the Papilionidae was significantly higher than those of all other families. Analysis of the monthly fluctuations in the beak mark rate and relative abundance of predators revealed that the higher beak mark rates observed for two butterfly families (Papilionidae and Nymphalidae) were significantly and positively related to predation pressure, while no significant relationship was found for other families (Lycaenidae, Pieridae and Hesperiidae). Beak marks in larger butterflies (Papilionidae and Nymphalidae) can be used as an indicator to evaluate the relative intensity of predation pressure in the field. 相似文献
956.
Ikumi Katano Ryoji Ito Tsutomu Kamisako Tomoo Eto Tomoyuki Ogura Kenji Kawai Hiroshi Suemizu Takeshi Takahashi Yutaka Kawakami Mamoru Ito 《Experimental Animals》2014,63(3):321-330
We have developed NOD-Rag2null IL-2Rγnull (NR2G)
mice similar to NOD-scidIL-2Rγnull (NOG) mice
that are known as an excellent host to generate humanized mice. To evaluate the usefulness
of NR2G mice as a host for humanized mice, the engraftment rates and differentiation of
human cells after human hematopoietic stem cell (HSC) transplantation were compared among
NR2G, NOG, and NOD-scid mice. For this purpose, the appropriate
irradiation doses to expand the niche for human stem cells in the bone marrow were first
determined. As a result, 8 and 2.5 Gy in adult, and 4 and 1 Gy in newborn NR2G and NOG
mice, respectively, were found to be appropriate. Next, 5 × 104 human umbilical
cord blood CD34+ cells were intravenously inoculated into irradiated adult or
newborn of the immunodeficient mice. These HSC transplantation experiments demonstrated
that both NR2G and NOG mice showed high engraftment rates compared with
NOD-scid mice, although NOG mice showed a slightly higher engraftment
rate than that for NR2G mice. However, no difference was found in the human cell
populations differentiated from HSCs between NR2G and NOG mice. The HSC transplantation
experiments to adults and newborns of two immunodeficient mice also revealed that the HSC
transplantation into newborn mice resulted in higher engraftment rate than those into
adults. These results showed that NR2G mice could be used as an alternative host to NOG
mice to generate humanized mice. 相似文献
957.
Junya Sato Mitsuo Kinugasa Seimi Satomi-Kobayashi Kinta Hatakeyama Aaron J. Knox Yujiro Asada Margaret E. Wierman Ken-ichi Hirata Yoshiyuki Rikitake 《PloS one》2014,9(9)
Identification of the regulators of vascular inflammation is important if we are to understand the molecular mechanisms leading to atherosclerosis and consequent ischemic heart disease, including acute myocardial infarction. Gene polymorphisms in family with sequence similarity 5, member C (FAM5C) are associated with an increased risk of acute myocardial infarction, but little is known about the function of this gene product in blood vessels. Here, we report that the regulation of the expression and function of FAM5C in endothelial cells. We show here that FAM5C is expressed in endothelial cells in vitro and in vivo. Immunofluorescence microcopy showed localization of FAM5C in the Golgi in cultured human endothelial cells. Immunohistochemistry on serial sections of human coronary artery showed that FAM5C-positive endothelium expressed intercellular adhesion molecule-1 (ICAM-1) or vascular cell adhesion molecule-1 (VCAM-1). In cultured human endothelial cells, the overexpression of FAM5C increased the reactive oxygen species (ROS) production, nuclear factor-κB (NF-κB) activity and the expression of ICAM-1, VCAM-1 and E-selectin mRNAs, resulting in enhanced monocyte adhesion. FAM5C was upregulated in response to inflammatory stimuli, such as TNF-α, in an NF-κB- and JNK-dependent manner. Knockdown of FAM5C by small interfering RNA inhibited the increase in the TNF-α-induced production of ROS, NF-κB activity and expression of these leukocyte adhesion molecule mRNAs, resulting in reduced monocyte adhesion. These results suggest that in endothelial cells, when FAM5C is upregulated in response to inflammatory stimuli, it increases the expression of leukocyte adhesion molecules by increasing ROS production and NF-κB activity. 相似文献
958.
Tomomitsu Tahara Tomoyuki Shibata Masaaki Okubo Takamitsu Ishizuka Masakatsu Nakamura Mitsuo Nagasaka Yoshihito Nakagawa Naoki Ohmiya Tomiyasu Arisawa Ichiro Hirata 《PloS one》2014,9(10)
Background
Epithelial-to-mesenchymal transition (EMT) is a phenomenon that allows the conversion of adherent epithelial cells to a mesenchymal cell phenotype, which enhances migratory capacity and invasiveness. Recent studies have suggested that EMT contributes to the pathogenesis of ulcerative colitis (UC). We investigated the promoter DNA methylation status of EMT-related genes in the colonic mucosa in UC.Methods
Colonic biopsies were obtained from the rectal inflammatory mucosa of 86 UC patients and the non-inflammatory proximal colonic mucosa of 10 paired patients. Bisulfite pyrosequencing was used to quantify the methylation of 5 candidate CpG island promoters (NEUROG1, CDX1, miR-1247, CDH1, and CDH13) and LINE1.Results
Using an unsupervised hierarchical clustering analysis, inflamed rectal mucosa was well separated from mucosa that appeared normal. The CDH1 and CDH13 promoters were significantly associated with patient age (p = 0.04, 0.03, respectively). A similar trend was found between those genes and the duration of disease (CDH1: p = 0.07, CDH13: p = 0.0002, mean of both: p<0.00001). Several positive associations were found between hypermethylation and severe clinical phenotypes (CDX1 and miR-1247 and a refractory phenotype: p = 0.04 and 0.006, respectively. miR-1247 and CDH1 hyper methylation and a more severe Mayo endoscopic subscore: miR-1247: p = 0.0008, CDH1: p = 0.03, mean of both: p = 0.003). When the severe clinical phenotype was defined as having any of five phenotypes (hospitalized more than twice, highest Mayo endoscopic subscore, steroid dependence, refractory, or a history of surgery) miR-1247 hypermethylation was associated with the same phenotype (p = 0.008).Conclusions
Our data suggest that variability in the methylation status of EMT-related genes is associated with more severe clinical phenotypes in UC. 相似文献959.
Tae-Jun Kwon Se-Kyung Oh Hong-Joon Park Osamu Sato Hanka Venselaar Soo Young Choi SungHee Kim Kyu-Yup Lee Jinwoong Bok Sang-Heun Lee Gert Vriend Mitsuo Ikebe Un-Kyung Kim Jae Young Choi 《Open biology》2014,4(7)
Mutations in five unconventional myosin genes have been associated with genetic hearing loss (HL). These genes encode the motor proteins myosin IA, IIIA, VI, VIIA and XVA. To date, most mutations in myosin genes have been found in the Caucasian population. In addition, only a few functional studies have been performed on the previously reported myosin mutations. We performed screening and functional studies for mutations in the MYO1A and MYO6 genes in Korean cases of autosomal dominant non-syndromic HL. We identified four novel heterozygous mutations in MYO6. Three mutations (p.R825X, p.R991X and Q918fsX941) produce a premature truncation of the myosin VI protein. Another mutation, p.R205Q, was associated with diminished actin-activated ATPase activity and actin gliding velocity of myosin VI in an in vitro analysis. This finding is consistent with the results of protein modelling studies and corroborates the pathogenicity of this mutation in the MYO6 gene. One missense variant, p.R544W, was found in the MYO1A gene, and in silico analysis suggested that this variant has deleterious effects on protein function. This finding is consistent with the results of protein modelling studies and corroborates the pathogenic effect of this mutation in the MYO6 gene. 相似文献
960.
Hushna Ara Naznin Daigo Kiyohara Minako Kimura Mitsuo Miyazawa Masafumi Shimizu Mitsuro Hyakumachi 《PloS one》2014,9(1)
Volatile organic compounds (VOC) were extracted and identified from plant growth-promoting fungi (PGPF), Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography–mass spectrometry (GC-MS). Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp.) significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst). Subsequently, m-cresol and methyl benzoate (MeBA) were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR) against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA) or Jasmonic acid (JA)/ethylene (ET) signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases. 相似文献