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91.
Justo R Alcolea MP Colom B Riera AN Gianotti M García-Palmer FJ 《Cellular and molecular life sciences : CMLS》2002,59(12):2199-2209
To establish the role of mitochondrial subpopulations in the mitochondrial maturation process, we studied morphological and
functional changes in the mitochondria of different mammalian conceptus tissues during the organogenic and the placentation
processes. Mitochondrial subpopulations of three different conceptus tissues, embryo and visceral yolk sac placenta on gestational
days 11, 12 and 13 and placenta on days 12 and 13, were examined morphologically by transmission electron microscopy. Cytochrome
oxidase activity and protein levels were also measured in each mitochondrial subpopulation. The results indicate two different
mitochondrial subpopulation profiles: a homogeneous one, which corresponds to immature mitochondria, and a heterogeneous one,
which represents the mature mitochondria. The three tissues studied show different morphologic and metabolic patterns of mitochondrial
maturation during the placentation process, rendering them suitable as experimental models to establish the p
ossible relationship between mitochondrial maturation and the mitochondrial subpopulations.
Received 5 August 2002; received after revision 23 September 2002; accepted 8 October 2002
RID="*"
ID="*"Corresponding author. 相似文献
92.
To understand effect of (-stacking interactions between the side chain of aromatic amino acids and the porphyrin ring on structures and properties in cytochrome b5 (cyt b5), the Phe58 residue was mutated to tyrosine and tryptophan, respectively by site-directed mutagenesis. The denaturation of cyt b5 F58W and F58Y toward guanidine hydrochloride was examined by UV-visible and fluorescence spectroscopy. The kinetics of heme transfer reactions between apo-myoglobin and the mutants were studied. The results indicated that the mutation of F58 residue for Y58 or W58 reduced the interaction between of peptide and the heme group, resulting in decrease of the Tm and Cm values of the proteins, increase of the heme transfer reaction rate, and shifts of the redox potential. 相似文献
93.
合成并表征了3种在苯环上具有推电子或拉电子取代基的新的不对称四苯基卟啉衍生物及其铁配合物。研究了其铁配合物作为细胞色素P450模拟酶对环己烷的羟化作用,并与结构类似的对称卟啉进行了比较。结果进一步证明,与对称金属卟啉相似,苯环上取代基性质和空间位阻对于金属卟啉的催化活性是十分重要的。不对称金属卟啉的催化活性比结构类似的对称金属卟啉的稍大。 相似文献
94.
Mitochondrial response and calcium ion change in apoptotic insect cells induced by SfaMNPV 总被引:1,自引:0,他引:1
XlUMeihong PENGJianxin HONGHuazhu 《科学通报(英文版)》2005,50(12):1191-1198
Mitochondrial responses and changes of calcium ions in apoptotic insect SL-1 cells induced by Syngrapha falcifera multiple nuclear polyhedrosis virus (SfaMNPV) are reported in this paper. By using Rhodamine 123 as a fluorescent labeling probe, flow cytometry analysis and confocal laser scanning microscope observation we observed that the mitochondrial transmembrane potential (△ψm) began to decrease in SL-1 cells at 4 h post infection and △ψm reduced continuously with the extension of virus infection. Western blotting indicated that the Bcl-2 level in the mitochondria gradually declined and was down- regulated. Cells undergoing apoptosis were found to have an elevation of cytochrome c in the cytosol and a corresponding decrease in the mitochondria, which indicated that cytochrome c was released from mitochondria into cytosol. These results suggest that mitochondrion-mediated apoptotic signal transduction pathway exists in apoptotic insect cell induced by SfaMNPV. Cytosolic free calcium ([Ca^2 ]i) concentration rapidly increased after SfaMNPV infection and the elevated calcium was tested to come partly from extracelllular calcium ion influx. Flow cytometry analysis indicated that the apoptosis in SL-1 cells was not influenced by established cytosolic calcium clamped conditions and the EGTA inhibiting calcium influx. Therefore, neither the elevation of cytosolic calcium ion nor extracellular calcium entry was the inducing factor of apoptosis, which hinted that the depletion of ER Ca^2 store contributed to SL-1 cell apoptosis induced by SfaMNPV. 相似文献
95.
测定了鱼巴亚科云南光唇鱼(Acrossocheilus yunnanensis)、宽头四须鱼巴(Barbodes laticeps)、抚仙金线鱼巴(Sinocyclocheilus tingi)和滇池金线鱼巴(Sinocyclocheilus grahami)4种鱼类线粒体细胞色素b基因DNA序列402bp,结合已知的云南倒刺鱼巴(Spinibarb denticulatus yunnanensis)和细尾长臀鱼巴(Mystacoleucus lepturus)的同源序列,组成1个6种代表鱼巴亚科5属鱼类的数据集.选用已知的云南鲴(Xenocypris yunnanensis)作为外群,采用邻接法、最大简约法和最大似然法构建了分子系统树.结果显示:倒刺鱼巴属(Spinibarbus)和光唇鱼属(Acrossocheilus)有较近的亲缘关系,四须鱼巴属(Barbodes)和长臀鱼巴属(Mystacoleucus)有较近的亲缘关系,而金线鱼巴属(Sinocyclocheilus)和它们的关系不能确定.上述结果与它们的地理分布基本吻合. 相似文献
96.
An apoptotic cell-free system containing cytosol and nuclei from normally cultured tobacco suspension cells was used to show that a spinach chloroplast preparation can induce apoptosis in nuclei, evidenced by DNA electrophoresis and fluorescence microscopy observations, Further study showed that the chloroplast preparation or its pellet (thylakoid membrane) after hypoosmotic or supersonic treatment still exhibited the apoptosis-inducing activity, but the supernatant had no effect, which indicates that the apoptosisinducing effector in the chloroplast preparation is water-insoluble. The induction of apoptosis by chloroplast preparation could be attenuated by Ac-DEVD-CHO, the specific inhibitor of Caspase-3, implying involvement of a Caspase-3-1ike protease during the process. Furthermore, extensive apoptosis in nuclei was induced by cytochrome b6/f on the thylakoid membrane, indicating that this important cytochrome complex may have an important role in the chloroplast-related apoptotic pathway. 相似文献
97.
The sequences of mitochondrial cytochrome b gene of cyprinid subfamily Leuciscinae are analyzed. Phylogenetic trees generated with methods of neighbor-joining, maximum likelihood and maximum parsimony with Phenacogrammus as an outgroup indicate that Leuciscinae is not a monophyletic group but includes two discrete subgroups. The East Asian group of the subfamily Leuciscinae, including the genera Ctenopharyngodon, Elopichthys, Luciobrama, Mylopharyngodon, Ochetobius, and Squaliobarbus, is close to Aristichthys and Hypophthalmichthys, and they form a monophyletic group which is distant from the leuciscine genera in Europe, Siberia and North America, such as Phoxinus, Leuciscus, Abramis, Rutilus, Chondrostoma, Alburnus, Opsopoedus, Lythrurus, and Pimephales. Our study suggests that the diversified East Asian group of the subfamily Leuciscinae should have an independent origination. 相似文献
98.
用AOT/异辛烷反胶团系统萃取了添加不同浓度镁离子的猪心提取液中的细胞包素C.其结果为:添加0.025mol/LMg2+的萃取率E.R,(ExtractRatio)为96.5%(氧化型和还原型平均值).添加0.3mol/LMg2+的萃取率为28.3%。萃取后水相的吸收光谱中,还原型细胞色素C在520nm、550nm的吸收峰值消失。120nm的吸收峰值显著降低。萃取有机相的吸收光谱中,还原型细胞包素C在420nm、520nm和550nm处的特征吸收峰值显著。经反萃取后水相的吸收光谱与提取液以及萃取有机相的吸收光谱相同。说明添WMg2+后,经AOT/异辛烷萃取和反萃取过程能将细胞包素C从猪心提取液中萃取分离出来。 相似文献
99.
The presence of phosphorylation form of D1 protein in its cross-linked aggregates in high light treated spinach leaves in vivo 总被引:5,自引:0,他引:5
Photosystem Ⅱ (PS Ⅱ ) is a pigment-protein com-plex that catalyses the primary photochemistry leading to oxygen evolution and electron flow in oxygenic phototrophs. The reaction center of PSⅡ is composed of the D1 and D2 proteins to which all the redox… 相似文献
100.
Ming Li Yuanguang Li Helin Sheng H. Tamate R. Masuda J. Nagata N. Ohtaishi 《科学通报(英文版)》1999,44(8):719-719
Since the musk deer distributed in the Dabie Mountains, Anhui was defined asMoschus moschiferus anhuiensis, its status has been disputed based on researches of morphology and ecology. This study further probed into its taxonomic
status with principal components analysis (PCA) on skull measurements and mtDNA cytochrome b sequences (367 bp) analysis so
as to clear its status. It is concluded that the figure and skull in Anhui musk deer are different from other species, and
DNA divergence between it and other species is 6.24%–7.90%, which belongs to inter-specific difference. Thus, the study defines
this musk deer as one distinct species,Moschus anhuiensis (Wang, Huet al.) 相似文献