Subcellular localization of 241Am in structural components of submerged macrophyte of the River Yenisei Elodea canadensis

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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Freeze-fracture cytochemistry: A goal set by Russell Steere in 1957

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014614x ◽

1993 ◽

Vol 51 ◽

pp. 60-61

Author(s):

Nicholas J Severs

Keyword(s):

Chemical Nature ◽

Biological Systems ◽

Freeze Fracture ◽

Structural Components ◽

Major Goal ◽

Membrane Biology ◽

Routine Application ◽

The Future ◽

Freeze Etching

In his pioneering demonstration of the potential of freeze-etching in biological systems, Russell Steere assessed the future promise and limitations of the technique with remarkable foresight. Item 2 in his list of inherent difficulties as they then stood stated “The chemical nature of the objects seen in the replica cannot be determined”. This defined a major goal for practitioners of freeze-fracture which, for more than a decade, seemed unattainable. It was not until the introduction of the label-fracture-etch technique in the early 1970s that the mould was broken, and not until the following decade that the full scope of modern freeze-fracture cytochemistry took shape. The culmination of these developments in the 1990s now equips the researcher with a set of effective techniques for routine application in cell and membrane biology.Freeze-fracture cytochemical techniques are all designed to provide information on the chemical nature of structural components revealed by freeze-fracture, but differ in how this is achieved, in precisely what type of information is obtained, and in which types of specimen can be studied.

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Microtubule motors and other maps

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015753x ◽

1990 ◽

Vol 48 (3) ◽

pp. 1-1

Author(s):

Richard B. Vallee

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Cytoplasmic Dynein ◽

Organelle Transport ◽

Structural Components ◽

Microtubule Associated Proteins ◽

Microtubule Motors ◽

Associated Proteins ◽

The Subject ◽

Intracellular Motility

Microtubules are involved in a number of forms of intracellular motility, including mitosis and bidirectional organelle transport. Purified microtubules from brain and other sources contain tubulin and a diversity of microtubule associated proteins (MAPs). Some of the high molecular weight MAPs - MAP 1A, 1B, 2A, and 2B - are long, fibrous molecules that serve as structural components of the cytamatrix. Three MAPs have recently been identified that show microtubule activated ATPase activity and produce force in association with microtubules. These proteins - kinesin, cytoplasmic dynein, and dynamin - are referred to as cytoplasmic motors. The latter two will be the subject of this talk.Cytoplasmic dynein was first identified as one of the high molecular weight brain MAPs, MAP 1C. It was determined to be structurally equivalent to ciliary and flagellar dynein, and to produce force toward the minus ends of microtubules, opposite to kinesin.

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Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180045 ◽

1990 ◽

Vol 48 (1) ◽

pp. 258-259

Author(s):

J.L. Carrascosa ◽

G. Abella ◽

S. Marco ◽

M. Muyal ◽

J.M. Carazo

Keyword(s):

Three Dimensional ◽

The Other ◽

Two Dimensional ◽

Series Method ◽

Three Dimensional Reconstruction ◽

Structural Components ◽

E Coli ◽

Dimensional Reconstruction ◽

Morphogenetic Factors ◽

Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

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Investigating the functional link between TMEM165 and SPCA1

Biochemical Journal ◽

10.1042/bcj20190488 ◽

2019 ◽

Vol 476 (21) ◽

pp. 3281-3293 ◽

Cited By ~ 2

Author(s):

Elodie Lebredonchel ◽

Marine Houdou ◽

Hans-Heinrich Hoffmann ◽

Kateryna Kondratska ◽

Marie-Ange Krzewinski ◽

...

Keyword(s):

Subcellular Localization ◽

Complete Loss ◽

Protein Family ◽

Uncharacterized Protein ◽

Functional Link ◽

P Type

TMEM165 was highlighted in 2012 as the first member of the Uncharacterized Protein Family 0016 (UPF0016) related to human glycosylation diseases. Defects in TMEM165 are associated with strong Golgi glycosylation abnormalities. Our previous work has shown that TMEM165 rapidly degrades with supraphysiological manganese supplementation. In this paper, we establish a functional link between TMEM165 and SPCA1, the Golgi Ca2+/Mn2+ P-type ATPase pump. A nearly complete loss of TMEM165 was observed in SPCA1-deficient Hap1 cells. We demonstrate that TMEM165 was constitutively degraded in lysosomes in the absence of SPCA1. Complementation studies showed that TMEM165 abundance was directly dependent on SPCA1's function and more specifically its capacity to pump Mn2+ from the cytosol into the Golgi lumen. Among SPCA1 mutants that differentially impair Mn2+ and Ca2+ transport, only the Q747A mutant that favors Mn2+ pumping rescues the abundance and Golgi subcellular localization of TMEM165. Interestingly, the overexpression of SERCA2b also rescues the expression of TMEM165. Finally, this paper highlights that TMEM165 expression is linked to the function of SPCA1.

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Subcellular localization and light-dark control of ornithine decarboxylase in the unicellular green alga Chlamydomonas reinhardtii

Physiologia Plantarum ◽

10.1034/j.1399-3054.2000.108004353.x ◽

2000 ◽

Vol 108 (4) ◽

pp. 353-360 ◽

Cited By ~ 16

Author(s):

Jürgen Voigt ◽

Bernd Deinert ◽

Peter Bohley

Keyword(s):

Subcellular Localization ◽

Chlamydomonas Reinhardtii ◽

Ornithine Decarboxylase ◽

Green Alga ◽

Dark Control ◽

Unicellular Green Alga

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The formation of information security culture of college students

Informatics and Education ◽

10.32517/0234-0453-2019-34-9-29-36 ◽

2019 ◽

pp. 29-36

Author(s):

I. D. Rudinskiy ◽

D. Ya. Okolot

Keyword(s):

College Students ◽

Information Security ◽

Information Society ◽

Technical Aspect ◽

Data Sources ◽

Structural Components ◽

Security Culture ◽

The Individual ◽

Information Security Culture ◽

Ability And Willingness

The article discusses aspects of the formation of information security culture of college students. The relevance of the work is due to the increasing threats to the information security of the individual and society due to the rapid increase in the number of information services used. Based on this, one of the important problems of the development of the information society is the formation of a culture of information security of the individual as part of the general culture in its socio-technical aspect and as part of the professional culture of the individual. The study revealed the structural components of the phenomenon of information security culture, identified the reasons for the interest in the target group of students. It justifies the need for future mid-level specialists to form an additional universal competency that ensures the individual’s ability and willingness to recognize the need for certain information, to identify and evaluate the reliability and reliability of data sources. As a result of the study, recommendations were formulated on the basis of which a culture of information security for college students can be formed and developed and a decomposition of this process into enlarged stages is proposed. The proposals on the list of disciplines are formulated, within the framework of the study of which a culture of information security can develop. The authors believe that the recommendations developed will help future mid-level specialists to master the universal competency, consisting in the ability and willingness to recognize the need for certain information, to identify and evaluate the reliability and reliability of data sources, as well as to correctly access the necessary information and its further legitimate use, which ultimately forms a culture of information security.

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