Journal of ultrastructure and molecular structure research最新文献_第9页

Spermiogenesis in the gall-midge Monarthropalpus buxi (Cecidomyiidae, Diptera) 布氏单肢瘿蚊精子发生的研究(蠓科，双翅目)

Journal of ultrastructure and molecular structure research Pub Date : 1988-08-01 DOI: 10.1016/0889-1605(88)90022-5

B.Jazdowska Zagrodzinska , R. Dallai

引用次数: 12

I-bands of striated muscle contain lateral struts 横纹肌的i型带包含侧支

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90055-9

Károly Trombitás, Peter H.W.W. Baatsen, Gerald H. Pollack

引用次数: 25

The cell wall structure of a magnesium-dependent Halobacterium, Halobacterium volcanii CD-2, from the Dead Sea 死海中依赖镁的盐杆菌，火山盐杆菌CD-2的细胞壁结构

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90062-6

Martin Kessel , E.Loren Buhle Jr. , Simone Cohen , Ueli Aebí

引用次数: 17

Three-dimensional structure of renal Na,K-ATPase determined from two-dimensional membrane crystals of the p1 form 肾Na, k - atp酶的三维结构由二维p1型膜晶体确定

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90061-4

Hans Hebert , Elisabeth Skriver , Margareta Söderholm , Arvid B. Maunsbach

{"title":"Three-dimensional structure of renal Na,K-ATPase determined from two-dimensional membrane crystals of the p1 form","authors":"Hans Hebert , Elisabeth Skriver , Margareta Söderholm , Arvid B. Maunsbach","doi":"10.1016/0889-1605(88)90061-4","DOIUrl":"10.1016/0889-1605(88)90061-4","url":null,"abstract":"<div><p>Electron microscopy and image processing were used to reconstruct a three-dimensional model of membrane-bound monomeric renal Na,K-ATPase from negatively stained two-dimensional crystals of the p1 type. Correlation methods were applied to obtain projection averages which were aligned by a phase difference minimization procedure. The self-consistency of the reconstruction process was high as determined by correlation between experimental projections and projections of the calculated model. The three-dimensional model of the Na,K-ATPase protomer in the p1 crystal form contains three characteristic domains, a protein dense ellipsoid, a small globular stain deficient domain, and a connecting low-contrast region. The latter is thought to correspond to the lipid-penetrating part of the Na,K-ATPase protomer. The location of this domain gives the protein an asymmetric distribution in the bilayer so that it is exposed primarily on one side proposed to correspond to the intracellular face.</p></div>","PeriodicalId":77743,"journal":{"name":"Journal of ultrastructure and molecular structure research","volume":"100 1","pages":"Pages 86-93"},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0889-1605(88)90061-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13988178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Ultrastructure of spinach thylakoids as seen in low-temperature and conventional embeddings 低温和常规包埋菠菜类囊体的超微结构

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90058-4

Claes Weibull , Per-Åke Alertsson

引用次数: 7

Bending of 9 + “1” axonemes of flatworm spermatozoa in hypotonic media: An experimental study 扁虫精子9 +“1”轴突在低渗介质中弯曲的实验研究

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90056-0

Jean-Lou Justine , Xavier Mattei

{"title":"Bending of 9 + “1” axonemes of flatworm spermatozoa in hypotonic media: An experimental study","authors":"Jean-Lou Justine , Xavier Mattei","doi":"10.1016/0889-1605(88)90056-0","DOIUrl":"10.1016/0889-1605(88)90056-0","url":null,"abstract":"<div><p>Spermatozoa of the monogenan <em>Amphibdella paronaperugiae</em> are fundamentally straight-shaped and made up of an anterior centriole followed by a 9 + “1” axoneme, associated with a filiform mitochondrion and nucleus. Observations were made of individuals in male phase, parasitic in the heart cavity of the torpedo-ray <em>Torpedo marmorata</em>, the blood of which is known to display a high osmolarity (900–1200 mOsm) primarily due to the presence of urea and sodium chloride. Spermatozoa were studied in ultrathin sections of whole parasites. When submitted to a low osmotic pressure, the spermatozoa of <em>Amphibdella</em> folded or coiled on themselves. Experiments were performed to induce these folds with media of varying osmolarity containing urea, sodium chloride, or both. Media of osmolarity higher than 600 mOsm did not induce folding; media of osmolarity about 300 mOsm induced folds. It is hypothesized that the folds of the spermatozoa are produced by folds of the 9 + “1” axoneme, related to water permeability of the sperm cell membrane. Several fixatives (glutaraldehyde in sodium cacodylate buffer, with addition of varying proportions of sucrose, sodium chloride, and urea) were tested; the osmolarity of the fixative was found to have no influence on sperm folds, probably because these folds are physiological phenomena induced only in living sperm cells, not in cells killed by the fixative.</p></div>","PeriodicalId":77743,"journal":{"name":"Journal of ultrastructure and molecular structure research","volume":"100 1","pages":"Pages 31-38"},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0889-1605(88)90056-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"53917138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Changes in the distribution of intramembranous particles and filipin-sterol complexes during epididymal maturation of golden hamster spermatozoa 金仓鼠精子附睾成熟过程中膜内颗粒和菲比-甾醇复合物分布的变化

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90057-2

F. Suzuki

引用次数: 37

The ultrastructure of fiber cells in primate lenses: A model for studying membrane senescence 灵长类动物晶状体纤维细胞的超微结构:研究膜衰老的一个模型

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90059-6

J.R. Kuszak , C.A. Ennesser , J. Umlas , M.S. Macsai-Kaplan , R.S. Weinstein

{"title":"The ultrastructure of fiber cells in primate lenses: A model for studying membrane senescence","authors":"J.R. Kuszak , C.A. Ennesser , J. Umlas , M.S. Macsai-Kaplan , R.S. Weinstein","doi":"10.1016/0889-1605(88)90059-6","DOIUrl":"10.1016/0889-1605(88)90059-6","url":null,"abstract":"<div><p>We have compared the surface morphology of the youngest (cortical) fiber cells with that of the most senescent (nuclear) fiber cells in monkey and baboon crystalline lenses by stereo scanning electron microscopy (SEM) and thick-section stereo transmission electron microscopy (TEM). Both the broad and the narrow faces of the most senescent fiber cells featured distinctive, polygonal areas (domains) of furrowed cell membrane. The domains ranged n size from 2.42 to 8.78 μm<sup>2</sup>. Stereopair SEM and TEM micrographs demonstrated precisely oriented microvilli measuring approximately 0.14 μm in diameter and ranging in length from 1.27 to 4.65 μm overlying each ridge in the domains. Formation of microvilli on senescent cells has been noted in other types of aging cells but they are precisely arranged and their function is unknown. Since every fiber cell remains in a fixed location (relative to other fiber cells) throughout life, the lens provides a unique model to study structure-function relationships of senescent microvilli <em>in situ</em>. The discovery of an age-related elaboration of numerous microvilli on senescent fiber cells of noncataractous lenses invalidates the currently accepted theory that close, parallel apposition of the broad faces of lens fiber cells is necessary for the lens to be transparent.</p></div>","PeriodicalId":77743,"journal":{"name":"Journal of ultrastructure and molecular structure research","volume":"100 1","pages":"Pages 60-74"},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0889-1605(88)90059-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14338790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 50

Fine structure of the A-band in cryo-sections diversity of M-band structure in chicken breast muscle 鸡胸肌m波段结构的多样性

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90054-7

Anne-Christine Edman , John M. Squire , Michael Sjöström

{"title":"Fine structure of the A-band in cryo-sections diversity of M-band structure in chicken breast muscle","authors":"Anne-Christine Edman , John M. Squire , Michael Sjöström","doi":"10.1016/0889-1605(88)90054-7","DOIUrl":"10.1016/0889-1605(88)90054-7","url":null,"abstract":"<div><p>Electron micrographs of longitudinal ultrathin cryo-sections and plastic sections of chicken pectoralis muscle together with their average images have been used to study in detail the axial structure of the M-band. It was found that M-band structure could vary markedly in different fibres, even within the white part of the muscle. Strong M-band density (“M-bridges”) could be seen at M4 and M4′ in all fibres. On the other hand the density at M1 or M6 could vary systematically. Some fibres (probably fast) had M1 strong, M6 weak (a “3-line” M-band), and the Z-band was narrow. Other fibres, especially (but not exclusively) in the red part of the muscle and probably slow, had M6 strong, M1 weak (a “4-line” M-band), and the Z0band was broad. However, the majority of fibres ranged in structure between those two extremes and had a more or less “5-line” M-band with M1 and M6 both strong and a Z-band of intermediate width. Since they were such a constant feature, the M4 lines may be the sites of the primarily structural component of the M-band, whereas the different proteins at M1 and M6 may vary in quantity according to the physiological needs of the fibre. Finally, detailed analysis sometimes revealed substructure within the strong M-bridge lines. This substructure may represent additional unknown M-band proteins or may be an indication of the shape of single proteins at these positions.</p></div>","PeriodicalId":77743,"journal":{"name":"Journal of ultrastructure and molecular structure research","volume":"100 1","pages":"Pages 1-12"},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0889-1605(88)90054-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14337452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 25

La spermiogenèse de Myzostomum sp. (Procoelomata, Myzostomida) 粘虫属（Procoelomata，Myzostomida）

Journal of ultrastructure and molecular structure research Pub Date : 1988-07-01 DOI: 10.1016/0889-1605(88)90060-2

Xavier Mattei, Bernard Marchand

{"title":"La spermiogenèse de Myzostomum sp. (Procoelomata, Myzostomida)","authors":"Xavier Mattei, Bernard Marchand","doi":"10.1016/0889-1605(88)90060-2","DOIUrl":"10.1016/0889-1605(88)90060-2","url":null,"abstract":"<div><p>The nucleus of the <em>Myzostomum</em> spermatid contains chromatin and protein granules. The single centriole gives rise to a 9 + 0 type flagellum and then migrates in the cytoplasm of the spermatid. A cytoplasmic canal is thus constituted toward which the mitochondria migrate. The nucleus becomes longer and 16 to 18 microtubules appear on its periphery, forming a rudimentary manchette. The cytoplasmic canal then opens along almost its whole length. The flagellum is thus in an extracellular position. The nuclear envelope breaks open, bringing the nuclear and cytoplasmic elements into direct contact. A nucleocytoplasmic derivative in which the chromatin is peripheral and the protein granules are in a central position is thus formed. The centriole, capped by a vesicle, undergoes a second forward migration which does not end until the distal extremity of the flagellum has gone past the posterior extremity of the nucleocytoplasmic derivative. The free-swimming part of the flagellum now constitutes the anterior portion of the spermatozoon. The vesicle attached to the centriole turns into a rod which protrudes at the front of the gamete. The microtubules of the manchette persist in the spermatozoon where they are arranged against the plasma membrane. The spermatozoon in propelled by two types of motion. The first, which is not very effective, causes a forward movement, with the flagellum in front. We suppose it is due to undulations which go from the centriole toward the extremity of the flagellum. The second, which is rapid and effective, produces a backward movement, with the flagellum behind. It appears to be due to the intervention of the microtubules which deform the nucleocytoplasmic derivative and transmit undulations to the flagellum, going from its distal extremity toward the centriole.</p></div>","PeriodicalId":77743,"journal":{"name":"Journal of ultrastructure and molecular structure research","volume":"100 1","pages":"Pages 75-85"},"PeriodicalIF":0.0,"publicationDate":"1988-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0889-1605(88)90060-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"53917219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11