scholarly journals Mitochondrial Protein Network: From Biogenesis to Bioenergetics in Health and Disease

2020 ◽  
Vol 22 (1) ◽  
pp. 1
Author(s):  
Alessandra Ferramosca
Keyword(s):  
Crucial Role ◽  
Mitochondrial Protein ◽  
Protein Network ◽  
Eukaryotic Cells ◽  
Double Membrane ◽  
Health And Disease ◽  
Membrane Bound

Mitochondria are double membrane-bound organelles which are essential for the viability of eukaryotic cells, because they play a crucial role in bioenergetics, metabolism and signaling [...]

scholarly journals Innenarchitektur der Zellkraftwerke — Membranfalten in Hochauflösung

BIOspektrum ◽  
2021 ◽  
Vol 27 (2) ◽  
pp. 161-164
Author(s):  
Till Stephan ◽  
Peter Ilgen ◽  
Stefan Jakobs
Keyword(s):  
Electron Microscopy ◽  
Protein Complex ◽  
Mitochondrial Protein ◽  
Light And Electron Microscopy ◽  
Super Resolution ◽  
Eukaryotic Cells ◽  
Inner Membrane ◽  
Double Membrane ◽  
Cellular Organelles

AbstractMitochondria are essential cellular organelles, which supply eukaryotic cells with the universal energy carrier adenosine triphosphate. These organelles feature a unique double-membrane architecture, which is formed by a smooth outer membrane and a highly folded inner membrane. Harnessing super-resolution light and electron microscopy, we investigate the role of MICOS, a large mitochondrial protein complex, in determining the complex folding of the inner membrane.

The ultrastructure of the double membrane-bound bodies and endoplasmic reticulum in serial sections of wheat spot mosaic-affected wheat plants

1990 ◽  
Vol 48 (3) ◽  
pp. 694-695
Author(s):  
M. H. Chen ◽  
C. Hiruki
Keyword(s):  
Endoplasmic Reticulum ◽  
High Resolution ◽  
Membrane Structure ◽  
Mosaic Disease ◽  
Serial Sections ◽  
Thin Sections ◽  
Double Membrane ◽  
Southern Alberta ◽  
Membrane Bound ◽  
Scanning Em

Wheat spot mosaic disease was first discovered in southern Alberta, Canada, in 1956. A hitherto unidentified disease-causing agent, transmitted by the eriophyid mite, caused chlorosis, stunting and finally severe necrosis resulting in the death of the affected plants. Double membrane-bound bodies (DMBB), 0.1-0.2 μm in diameter were found to be associated with the disease.Young tissues of leaf and root from 4-wk-old infected wheat plants were fixed, dehydrated, and embedded in Spurr’s resin. Serial sections were collected on slot copper grids and stained. The thin sections were then examined with a Hitachi H-7000 TEM at 75 kV. The membrane structure of the DMBBs was studied by numbering them individually and tracing along the sections to see any physical connection with endoplasmic reticulum (ER) membranes. For high resolution scanning EM, a modification of Tanaka’s method was used. The specimens were examined with a Hitachi Model S-570 SEM in its high resolution mode at 20 kV.

Portein-gold labelling of ultrathin sections of wheat spot mosaic-affected wheat plants

1990 ◽  
Vol 48 (3) ◽  
pp. 680-681
Author(s):  
K. S. Zaychuk ◽  
M. H. Chen ◽  
C. Hiruki
Keyword(s):  
Osmium Tetroxide ◽  
Rnase A ◽  
Leaf Ultrastructure ◽  
Double Membrane ◽  
Young Root ◽  
Leaf Tissues ◽  
Membrane Bound ◽  
Ultrathin Sections ◽  
Gold Labelling ◽  
Electron Dense Core

Wheat spot mosaic (WSpM), which frequently occurs with wheat streak mosaic virus was first reported in 1956 from Alberta. Singly isolated, WSpM causes chlorotic spots, chlorosis, stunting, and sometimes death of the wheat plants. The vector responsible for transmission is the eriophyid mite, Eriophyes tulipae Kiefer. The examination of leaf ultrastructure by electron microscopy has revealed double membrane bound bodies (DMBB’s) 0.1-0.2 μm in diameter. Dispersed fibrils within these bodies suggested the presence of nucleic acid. However, neither ribosomes characteristic of bacteria, mycoplasma and the psittacosis group of organisms nor an electron dense core characteristic of many viruses was commonly evident.In an attempt to determine if the DMBB’s contain nucleic acids, RNase A, DNase I, and lactoferrin protein were conjugated with 10 nm colloidal gold as previously described. Young root and leaf tissues from WSpM-affected wheat plants were fixed in glutaraldehyde, postfixed in osmium tetroxide,and embedded in Spurr’s resin.

Single- or double-membrane-bound vesicles and P, Ca, and Fe-containing granules in Xanthomonas citri cultured on a solid medium

Micron ◽  
2021 ◽  
Vol 143 ◽  
pp. 103024
Author(s):  
Junhyung Park ◽  
A Reum Je ◽  
Sang Gil Lee ◽  
Jae Hyuck Jang ◽  
Yang Hoon Huh ◽  
...  
Keyword(s):  
Solid Medium ◽  
Xanthomonas Citri ◽  
Double Membrane ◽  
Membrane Bound

Zoospore ultrastructure in the genus Rhizophydium (Chytridiales)

1978 ◽  
Vol 56 (19) ◽  
pp. 2380-2404 ◽  
Author(s):  
D. J. S. Barr ◽  
V. E. Hadland-Hartmann
Keyword(s):  
Membrane System ◽  
Double Membrane ◽  
Lipid Globule ◽  
Lateral Posterior ◽  
Membrane Bound ◽  
Relationship Of ◽  
The Relationship ◽  
Posterior Position ◽  
Compact Cluster ◽  
Peripheral Cytoplasm

The zoospore ultrastructure of 12 species of Rhizophydium is described. Species include the following: R. chlorogonii (Serbinow) Jaczewski; R. constantineani Saccardo; R. haynaldii (Schaarschmidt) Fischer; R. capillaceum Barr; two morphologically and cytologically different species, each previously identified as R. sphaerotheca Zopf; R. patellarium Scholz; R. biporosum (Couch) Barr; R. subangulosum (Braun) Rabenhorst; R. laterale (Braun) Rabenhorst; R. sphaerocarpum (Zopf) Fischer var. spirogyrae Barr; and two isolates of R. pollinis-pini (Braun) Zopf. The Rhizophydium zoospore is basically similar to the Chytridium zoospore having (1) the nucleus, a compact cluster of ribosomes, one or more mitochondria, and a microbody – lipid globule complex compartmentalized into the core of the zoospore by a double membrane system and (2) two to five microtubules connecting one side of the kinetosome to the rumposome on the lipid globule surface and thus anchoring the lipid globule in a lateral–posterior position in the zoospore. Rhizophydium patellarium does not have kinetosome-associated microtubules or a rumposome but does have the membrane-bound core area. In all species, a microbody and mitochondrion are associated with the lipid globule. The number of mitochondria varies from 1 in some species to several or to over 30 in other species. In one isolate of R. pollinis-pini, there is 1 large mitochondrion and in the other there were 30–35 small mitochondria. The peripheral cytoplasm of all species contains clusters of vesicles or endoplasmic reticulum which bud from the double membrane system, vesicles of moderate electron density, and vacuoles of various sizes; R. capillaceum, R. patellarium, and R. subangulosum have in addition vesicles which contain very electron-dense material. Rhizophydium capillaceum and R. sphaerocarpum zoospores have virus-like particles and the R. biporosum zoospore contains a paracrystalline body. The taxonomic significance of the observations and the relationship of Rhizophydium to other chytrids are stressed in the Discussion.

scholarly journals Toward a better understanding of folate metabolism in health and disease

2018 ◽  
Vol 216 (2) ◽  
pp. 253-266 ◽  
Author(s):  
Yuxiang Zheng ◽  
Lewis C. Cantley
Keyword(s):  
Cell Proliferation ◽  
Epigenetic Regulation ◽  
Historical Perspective ◽  
Mitochondrial Protein ◽  
Protein Translation ◽  
Folate Metabolism ◽  
Cellular Functions ◽  
Biochemical Processes ◽  
Health And Disease ◽  
Thymidine Monophosphate

Folate metabolism is crucial for many biochemical processes, including purine and thymidine monophosphate (dTMP) biosynthesis, mitochondrial protein translation, and methionine regeneration. These biochemical processes in turn support critical cellular functions such as cell proliferation, mitochondrial respiration, and epigenetic regulation. Not surprisingly, abnormal folate metabolism has been causally linked with a myriad of diseases. In this review, we provide a historical perspective, delve into folate chemistry that is often overlooked, and point out various missing links and underdeveloped areas in folate metabolism for future exploration.

scholarly journals Bacterial tail anchors can target to the mitochondrial outer membrane

2017 ◽  
Author(s):  
Güleycan Lutfullahoğlu Bal ◽  
Abdurrahman Keskin ◽  
Ayşe Bengisu Seferoğlu ◽  
Cory D. Dunn
Keyword(s):  
Outer Membrane ◽  
Protein Translocation ◽  
Mitochondrial Protein ◽  
Eukaryotic Cell ◽  
Eukaryotic Cells ◽  
Mitochondrial Outer Membrane ◽  
Bacterial Proteins ◽  
Rate Limiting Step ◽  
Protein Entry ◽  
Rate Limiting

ABSTRACTDuring the generation and evolution of the eukaryotic cell, a proteobacterial endosymbiont was refashioned into the mitochondrion, an organelle that appears to have been present in the ancestor of all present-day eukaryotes. Mitochondria harbor proteomes derived from coding information located both inside and outside the organelle, and the rate-limiting step toward the formation of eukaryotic cells may have been development of an import apparatus allowing protein entry to mitochondria. Currently, a widely conserved translocon allows proteins to pass from the cytosol into mitochondria, but how proteins encoded outside of mitochondria were first directed to these organelles at the dawn of eukaryogenesis is not clear. Because several proteins targeted by a carboxyl-terminal tail anchor (TA) appear to have the ability to insert spontaneously into the mitochondrial outer membrane (OM), it is possible that self-inserting, tail-anchored polypeptides obtained from bacteria might have formed the first gate allowing proteins to access mitochondria from the cytosol. Here, we tested whether bacterial TAs are capable of targeting to mitochondria. In a survey of proteins encoded by the proteobacterium Escherichia coli, predicted TA sequences were directed to specific subcellular locations within the yeast Saccharomyces cerevisiae. Importantly, TAs obtained from DUF883 family members ElaB and YqjD were abundantly localized to and inserted at the mitochondrial OM. Our results support the notion that eukaryotic cells are able to utilize membrane-targeting signals present in bacterial proteins obtained by lateral gene transfer, and our findings make plausible a model in which mitochondrial protein translocation was first driven by tail-anchored proteins.

Macronuclear differentiation during oral regeneration in Stentor coeruleus

1975 ◽  
Vol 19 (3) ◽  
pp. 531-541
Author(s):  
J.J. Paulin ◽  
A.S. Brooks
Keyword(s):  
Late Stage ◽  
Axial Plane ◽  
Double Membrane ◽  
Perinuclear Cytoplasm ◽  
Nuclear Events ◽  
Membrane Bound ◽  
Stentor Coeruleus

The moniliform macronucleus of Stentor coeruleus coalesces and renodulates during division, reorganization and regeneration. These nuclear events are spatially and temporally synchronized with oral primordium development occurring at stages six and seven of membranellar morphogenesis. Coalesced, elongating and early renodulating macronuclei at states six and seven contained microtubules within double membrane-bound channels, passing through the nucleus parallel to the long axis. The number of microtubules per channel varied between 4 and 23. Microtubules were also found in the perinuclear cytoplasm at these stages, forming a loose network around the nucleus. The microtubules and channels are absent in control cells and macronuclei of regenerating cells prior to stage six. These transient microtubules and channels appearing in late stage six and stage seven may provide the axial plane on which elongation of the macronucleus proceeds.

Peroxisome Biogenesis: Something Old, Something New, Something Borrowed

Physiology ◽  
2010 ◽  
Vol 25 (6) ◽  
pp. 347-356 ◽  
Author(s):  
Fred D. Mast ◽  
Andrei Fagarasanu ◽  
Barbara Knoblach ◽  
Richard A. Rachubinski
Keyword(s):  
Cellular Differentiation ◽  
Eukaryotic Cells ◽  
Peroxisome Biogenesis ◽  
Metabolic Processes ◽  
Oxidative Reactions ◽  
Membrane Bound ◽  
Organismal Development

Eukaryotic cells are characterized by their varied complement of organelles. One set of membrane-bound, usually spherical compartments are commonly grouped together under the term peroxisomes. Peroxisomes function in regulating the synthesis and availability of many diverse lipids by harnessing the power of oxidative reactions and contribute to a number of metabolic processes essential for cellular differentiation and organismal development.

Interplay between engineered nanomaterials and microbiota

2020 ◽  
Author(s):  
Yirong Zhang ◽  
Monika Mortimer ◽  
Liang-Hong Guo
Keyword(s):  
Human Health ◽  
Crucial Role ◽  
Engineered Nanomaterials ◽  
Health And Disease

The growing evidence of the microbiome’s crucial role in human health and disease has prompted research on understanding the impacts of engineered nanomaterials (ENMs) on commensal microorganisms. Accordingly, the number...

Sign in / Sign up

Export Citation Format

Share Document