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131.
Hirata H Lopes GS Jurkiewicz A Garcez-do-Carmo L Smaili SS 《Neurochemical research》2012,37(2):238-243
Endoplasmic reticulum (ER) and mitochondria are intracellular organelles and their interactions are directly involved in different
processes such as Ca2+ signaling in cell survival and death mechanisms. Bcl-2 is an anti-apoptotic protein intrinsically related to ER and mitochondria,
modulating Ca2+ content in these organelles. We investigated the effects of Bcl-2 overexpression on ER and mitochondrial Ca2+ dynamics in PC12 cells. Bcl-2 overexpressing and control cells were loaded with Fura 2/AM and stimulated with different drugs.
Results showed that in Bcl-2 cells, ACh induced a lower Ca2+ response compared to control. Ca2+ release induced by TG was decreased in Bcl-2 cells, however, it was greater in Caff induced Ca2+ rise. In addition, FCCP induced a higher Ca2+ release in Bcl-2 cells. These results suggest that Bcl-2 overexpression modulate the ER Ca2+ pools differently and the release of ER Ca2+ may increase mitochondrial Ca2+ accumulation. These alterations of intracellular Ca2+ stores are important mechanisms for the control of Ca2+ signaling. 相似文献
132.
It is important for the proper execution of cell division in both mitosis and meiosis that the chromosome segregation, cytokinesis, and partition of cell organelles progress in smooth coordination. We show here that the mitochondria inheritance is closely linked with microtubules during meiotic divisions in Drosophila males. They are first clustered in a cell equator at metaphase associated with astral microtubules and then distributed along central spindle microtubules after anaphase. The molecular mechanism for the microtubule-dependent inheritance of mitochondria in male meiosis has not been demonstrated yet. We first isolated mutations for a larp gene that is highly conserved among eukaryotes and showed that these mutant males exhibited multiple meiotic phenotypes such as a failure of chromosome segregation, cytokinesis, and mitochondrial partition. Our cytological examination revealed that the mutants showed defects in spindle pole organization and spindle formation. The larp encodes a Drosophila orthologue of a La-related protein containing a domain exhibiting an outstanding homology with a La type RNA-binding protein. Surprisingly, the dLarp protein is localized in the cytoplasm of the male germ line cells, as observed by its distinct co-localization with mitochondria in early spermatocytes and during meiotic divisions. We discuss here the essential role that dLarp plays in multiple processes in Drosophila male meiosis. 相似文献
133.
Yugo Kimura Tadamichi Akagi Masanori Hangai Kohei Takayama Tomoko Hasegawa Kenji Suda Munemitsu Yoshikawa Hiroshi Yamada Hideo Nakanishi Noriyuki Unoki Hanako Ohashi Ikeda Nagahisa Yoshimura 《PloS one》2014,9(12)
Purpose
To investigate whether lamina cribrosa (LC) defects are associated with optic disc morphology in primary open angle glaucoma (POAG) eyes with high myopia.Methods
A total of 129 POAG patients and 55 age-matched control subjects with high myopia were evaluated. Three-dimensional scan images obtained by swept source optical coherence tomography were used to detect LC defects. Radial B-scans and infrared images obtained by spectral domain optical coherence tomography were used to measure β-peripapillary atrophy (PPA) lengths with and without Bruch''s membrane (BM) (temporal, nasal, superior, and inferior), tilt angle (vertical and horizontal), and disc diameter (transverse and longitudinal). Peripapillary intrachoroidal cavitations (PICCs), disc area, ovality index, and cyclotorsion of the optic disc were analyzed as well.Results
LC defects were found in 70 of 129 (54.2%) POAG eyes and 1 of 55 (1.8%) control eyes (P<0.001). Age, sex, spherical equivalent, axial length, intraocular pressure, and central corneal thickness were not significantly different among POAG eyes with LC defects, POAG eyes without LC defects, and control eyes. Temporal PPA lengths without BM in all three groups correlated significantly with vertical and horizontal tilt angles, although no PPA length with BM correlated significantly with any tilt angle. PICCs were detected more frequently in POAG eyes with LC defects than those without LC defects (P = 0.01) and control eyes (P = 0.02). POAG eyes with LC defects showed a smaller ovality index (P = 0.004), longer temporal PPA without BM (P<0.001), and larger vertical/horizontal tilt angles (vertical, P<0.001; horizontal, P = 0.01), and transverse diameter (P = 0.01). In multivariate analysis for the presence of LC defects, presence of POAG (P<0.001) and vertical tilt angle (P<0.001) were identified as significant.Conclusions
The presence of LC defects was associated with myopic optic disc morphology in POAG eyes with high myopia. 相似文献134.
135.
Shin-ichi Takenaka Tomotaka Kawayama Haruki Imaoka Yuki Sakazaki Hanako Oda Yoichiro Kaku Masanobu Matsuoka Masaki Okamoto Seiya Kato Kentaro Yamada Tomoaki Hoshino 《Biochemical and biophysical research communications》2014
Patients with severe COPD are known to have comorbidities such as emaciation, cor pulmonale and right heart failure, muscle weakness, hyperlipemia, diabetes mellitus, osteoporosis, muscle atrophy, arterial sclerosis, hypertension, and depression. Therefore, treatment for COPD needs to focus on these comorbidities as well as the lungs. We previously reported a new mouse model of COPD utilizing the human surfactant protein C promoter SP-C to drive the expression of mature mouse IL-18 cDNA; constitutive IL-18 overproduction in the lungs of transgenic (Tg) mice induces severe emphysematous change, dilatation of the right ventricle, and mild pulmonary hypertension with aging. In the present study, we evaluated the progression of comorbidity in our COPD model. In female Tg mice, significant weight loss was observed at 16 weeks and beyond, when compared with control wild-type (WT) mice. This weight loss was suppressed in IL-13-deficient (knockout; KO) Tg mice. Muscle weight and bone mineral density were significantly decreased in aged Tg mice relative to control WT and IL-13 KO Tg mice. The aged Tg mice also showed impaired glucose tolerance. IL-18 and IL-13 may play important roles in the pathogenesis of comorbidity in COPD patients. 相似文献
136.
Ikeda Y Shimura H Kitahara R Masuta C Ezawa T 《Molecular plant-microbe interactions : MPMI》2012,25(7):1005-1012
Arbuscular mycorrhizal (AM) fungi form mutualistic associations with most land plants and enhance phosphorus uptake of the host plants. Fungal viruses (mycoviruses) that possess a double-stranded RNA (dsRNA) genome often affect plant-fungal interactions via altering phenotypic expression of their host fungi. The present study demonstrates, for the first time, the presence of dsRNAs, which are highly likely to be mycoviruses, in AM fungi. dsRNA was extracted from mycelia of Glomus sp. strain RF1, purified, and subjected to electrophoresis. The fungus was found to harbor various dsRNA segments that differed in size. Among them, a 4.5-kbp segment was termed Glomus sp. strain RF1 virus-like medium dsRNA (GRF1V-M) and characterized in detail. The GRF1V-M genome segment was 4,557 nucleotides in length and encoded RNA-dependent RNA polymerase and a structural protein. GRF1V-M was phylogenetically distinct and could not be assigned to known genera of mycovirus. The GRF1V-M-free culture line of Glomus sp. strain RF1, which was raised by single-spore isolation, produced twofold greater number of spores and promoted plant growth more efficiently than the GRF1V-M-positive lines. These observations suggest that mycoviruses in AM fungi, at least some of them, have evolved under unique selection pressures and are a biologically active component in the symbiosis. 相似文献
137.
138.
Subseafloor microbial communities associated with rapid turbidite deposition in the Gulf of Mexico continental slope (IODP Expedition 308) 总被引:1,自引:0,他引:1
Takuro Nunoura Bruno Soffientino Anna Blazejak Jungo Kakuta Hanako Oida Axel Schippers & Ken Takai 《FEMS microbiology ecology》2009,69(3):410-424
The subseafloor microbial communities in the turbidite depositional basins Brazos-Trinity Basin IV (BT Basin) and the Mars-Ursa Basin (Ursa Basin) on the Gulf of Mexico continental slope (IODP holes U1319A, U1320A, U1322B and U1324B) were investigated by PCR-dependent molecular analyses targeted to the small subunit (SSU) rRNA genes, dsrA and mcrA , and hydrogenase activity measurements. Biomass at both basins was very low, with the maximum cell or the SSU rRNA gene copy number <1 × 107 cells mL−1 or copies g−1 sediments, respectively. Hydrogenase activity correlated with biomass estimated by SSU rRNA gene copy number when all data sets were combined. We detected differences in the SSU rRNA gene community structures and SSU rRNA gene copy numbers between the basin-fill and basement sediments in the BT Basin. Examination of microbial communities and hydrogenase activity in the context of geochemical and geophysical parameters and sediment depositional environments revealed that differences in microbial community composition between the basin-fill and basement sediments in the BT Basin were associated with sedimentation regimes tied to the sea-level change. This may also explain the distributions of relatively similar archaeal communities in the Ursa Basin sediments and basement sediments in the BT Basin. 相似文献
139.
Lawrence Kurowski Andrew L. Krause Hanako Mizuguchi Peter Grindrod Robert A. Van Gorder 《Bulletin of mathematical biology》2017,79(10):2302-2333
We extend two-species models of individual aggregation or clustering to two-dimensional spatial domains, allowing for more realistic movement of the populations compared with one spatial dimension. We assume that the domain is bounded and that there is no flux into or out of the domain. The motion of the species is along fitness gradients which allow the species to seek out a resource. In the case of competition, species which exploit the resource alone will disperse while avoiding one another. In the case where one of the species is a predator or generalist predator which exploits the other species, that species will tend to move toward the prey species, while the prey will tend to avoid the predator. We focus on three primary types of interspecies interactions: competition, generalist predator–prey, and predator–prey. We discuss the existence and stability of uniform steady states. While transient behaviors including clustering and colony formation occur, our stability results and numerical evidence lead us to believe that the long-time behavior of these models is dominated by spatially homogeneous steady states when the spatial domain is convex. Motivated by this, we investigate heterogeneous resources and hazards and demonstrate how the advective dispersal of species in these environments leads to asymptotic steady states that retain spatial aggregation or clustering in regions of resource abundance and away from hazards or regions or resource scarcity. 相似文献
140.
Hanako Shimura Mai Sadamoto Mayumi Matsuura Takayuki Kawahara Shigeo Naito Yasunori Koda 《Mycorrhiza》2009,19(7):515-515