• 제목/요약/키워드: mitochondria

검색결과 1,652건 처리시간 0.027초

마이크로파 조사에 의한 세포 미세구조의 고정 효과 (Fixation of Cellular Ultrastructure by the Microwave Irradiation)

  • 신길상;김완종;전진석
    • Applied Microscopy
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    • 제26권4호
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    • pp.401-410
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    • 1996
  • The microwave fixator has recently been introduced in morphological research. The present study was carried out to investigate the ultrastructural effects of microwave fixation of rat brain. kidney, liver and skeletal muscle tissues. The results are as follows: In the case of microwave fixed cerebrum. the cytoplasmic processes of neurons and the various membranous organelles such as nuclear envelope, mitochondria, rough endoplasmic reticulum and Golgi apparatus were well preserved, The myelin sheath wrapping neuronal axon was prominent. Microwave fixed hepatocytes showed the microvilli on the free surface of bile canaliculus, the evident nucleolar components, and typical organelles. In nephron, ultrastructures of glomerulus and Bowman's capsule were preserved, and also tubular wall were structurally observed. Among the skeletal muscle cells, plentiful collagen fibers were appeared, myofibrils and mitochondria were typically observed. In conclusion, the microwave fixation procedures result in an good preservation of the tissues and would be time- and reagent-saving.

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CoMIC, the hidden dynamics of mitochondrial inner compartments

  • Cho, Bongki;Sun, Woong
    • BMB Reports
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    • 제50권12호
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    • pp.597-598
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    • 2017
  • Mitochondria have evolutionarily, functionally and structurally distinct outer- (OMM) and inner-membranes (IMM). Thus, mitochondrial morphology is controlled by independent but coordinated activity of fission and fusion of the OMM and IMM. Constriction and division of the OMM are mediated by endocytosis-like machineries, which include dynamin-related protein 1 with additional cytosolic vesicle scissoring machineries such as actin filament and Dynamin 2. However, structural alteration of the IMM during mitochondrial division has been poorly understood. Recently, we found that the IMM and the inner compartments undergo transient and reversible constriction prior to the OMM division, which we termed CoMIC, ${\underline{C}}onstriction$ ${\underline{o}}f$ ${\underline{M}}itochondrial$ ${\underline{I}}nner$ ${\underline{C}}ompartment$. In this short review, we further discuss the evolutionary perspective and the regulatory mechanism of CoMIC during mitochondrial division.

미국흰불나방(Hyphantria cunea Drury)에 대한 Bacillus thuringiensis 내독소단백질의 독성효과에 관한 연구 (Studies on the Toxicity of $\delta$-endotoxin of Bacillus thuringiensis to the Several Tissues of Hyphantria cunea Drury)

  • 전향미;조자향;강석권;서숙재
    • 한국잠사곤충학회지
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    • 제37권1호
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    • pp.62-67
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    • 1995
  • Bacillus thuringiensis(Bt) var, kurstaki의 내독소 단백질을 섭취한 미국천불나방(Hyphantria cunea)의 유충에서 중장과 지방체조직의 세포 미세구조변화를 투과전자현미경으로 조사하였다. Bt 내독소 단백질은 중장 원주상피세포에 있어서 미세융모의 파괴, 소포체 구형화, 기저층 소실, 리보솜 탈락, 세포내 소기관의 파괴 등을 초래하였다. 또한, 지방체 세포에서도 역시 소포체의 구형화와 미토콘드리아의 변형 등 세포미세구조의 변화를 유발시켰다.

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느타리버섯 중의 Light-Induced Mitochondrial ATPase에 관한 연구 -유기물 효과- (Studies on Light-Induced Mitochondrial ATPase in Pleurotus ostreatus -Effects of Organic Compounds-)

  • 이호연;민태진
    • 한국균학회지
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    • 제20권1호
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    • pp.51-57
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    • 1992
  • Mitochondria in Pleurotus ostreatus were isolated and purified by stepped sucrose density gradient centrifugation, to compare the effects of organic compound on the activities of mitochondrial ATPase in Basidiomycotina with those in mammalian cell. The effects of N, N'-dicycio-hexylcarbodiimide (DCCD), carbonyl cyanide m-chlorophenylhydrazone (CCCP), sodium azide and aurovertin known as compounds to be related to electron transfer system in mitochondria were studied. A activity of mitochondrial ATPase was inhibited by 64%, 57% and 53% in the presence of 0.25 mM DCCD, 0.02 mM sodium azide and 1.5 $({\mu}g/mg\;of\;protein)$ aurovertin B, respectively. It was stimulated by 22% in the presence of 0.15 ${\mu}M$ CCCP.

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Refolding of Acid-Unfolded Globin to Hemoglobin

  • 이종우
    • 대한의생명과학회지
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    • 제11권1호
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    • pp.85-88
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    • 2005
  • Hemoglobin is oxygen carrier protein within erythrocyte in blood. Apoprotein of this, globin, is synthesized in the cytosol but it's cofactor, heme, is synthesized in the mitochondria. It has not been known very well how globin receives the heme from mitochondria and folds to hemoglobin. In this folding process, the initial structure of globin seems to be very important. A small volume of globin at acid pH was added rapidly into the bulk of an egg phosphatidylcholine $60\%$ liposome, containing hemins, at neutral pH according to the Rapid Dilution method. It was observed that an acid-induced unfolding structure of globin is initially needed to receive hemins from the lipid bilayer of liposomes. Also, this conclusion was confirmed with the absorption spectrum of the refolded globin separated by centrifugation.

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오리와 거위의 정자완성과 정자에 관한 전자현미경적 연구 (Electron-Microscopic Studies on the Spermiogenesis and the Spermatozoa of the Drake and the Gander)

  • 배대식;김종욱
    • 한국가축번식학회지
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    • 제11권3호
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    • pp.206-217
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    • 1987
  • Testes from the drake and the gander have been examined by the electron microscopy in thin sections in order to examine the spermiogenesis and the structure of spermatozoa. The spermiogenesis can be divided into three stages: early spermatid, nuclear elongation, and matured spermatid. In the early spermatid of the drake, there are thread-like material in the nucleus, a prominent nuclear envelope around the nucleus, and big lumens in the cytoplasm. The shape of the gander's mitochondria in the early spermatid is slender compared to that of the drake, and the inner membrane of the mitochondria is thicker than the outer membrane. The distal centriole of the drake and the gander in the early spermatid is a long hollow cylinder form. In the nuclear elongation stage, elongated nucleus forms two or three cross sections in one spermatid cell and it is surrounded by the amorphous sheath. The nucleus of the matured spermatid is compact and its apical end is covered with acrosome cap and acrosome spine. The axoneme is surrounded by the amorphous material.

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Acacetin의 HeLa 세포 Apoptosis 유도 효과 (Effect of Acacetin on the Apoptosis Induction of HeLa Cells)

  • 한수정;김안근
    • 약학회지
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    • 제59권1호
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    • pp.17-22
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    • 2015
  • In this study, we examined the effect of acacetin on the apoptosis induction of HeLa human cervical cancer cells. The results showed that acacetin inhibited the cell viability and induced apoptosis, leading to PARP cleavage and activation of caspase-9, -3, and -7. Moreover, acacetin-induced apoptosis was attenuated by a broad caspase inhibitor, z-VAD-fmk. Also, acacetin resulted in a loss of mitochondria membrane potential. Taken together, our results demonstrate that the induction of apoptosis by acacetin in HeLa cells is associated with caspase activation via the mitochondria pathway.

Apoptotic Signaling Pathways: Caspases and Stress-Activated Protein Kinases

  • Cho, Ssang-Goo;Choi, Eui-Ju
    • BMB Reports
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    • 제35권1호
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    • pp.24-27
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    • 2002
  • Apoptotic cell death is an active process mediated by various signaling pathways, which include the caspase cascade and the stress-activated protein kinase pathways. The caspase cascade is activated by two distinct routes: one from cell surface and the other from mitochondria. Activation of the route from cell surface requires the cellular components that include membrane receptors, adaptor proteins such as TRADD and FADD, and caspase-8, while activation of the other from mitochondria requires Apaf-1, caspase-9, and cytosolic cytochrome c. On the other hand, persistent stimulation of the stress-activated protein kinase pathway is also shown to mediate apoptosis in many cell types. Gene-targeting studies with jnk- or jip-null mice, in particular, strongly suggest that this signaling pathway plays a pivotal role in the cellular machinery for apoptosis.