Characterization of a nuclear compartment shared by nuclear bodies applying ectopic protein expression and correlative light and electron microscopy

Sites of replication in synchronized HeLa cells were visualized by light and electron microscopy; cells were permeabilized and incubated with biotin-16-dUTP, and incorporation sites were immunolabelled. Electron microscopy of thick resinless sections from which approximately 90% chromatin had been removed showed that most DNA synthesis occurs in specific dense structures (replication factories) attached to a diffuse nucleoskeleton. These factories appear at the end of G1-phase and quickly become active; as S-phase progresses, they increase in size and decrease in number like sites of incorporation seen by light microscopy. Electron microscopy of conventional thin sections proved that these factories are a subset of nuclear bodies; they changed in the same characteristic way and contained DNA polymerase alpha and proliferating cell nuclear antigen. As replication factories can be observed and labelled in non-permeabilized cells, they cannot be aggregation artifacts. Some replication occurs outside factories at discrete sites on the diffuse skeleton; it becomes significant by mid S-phase and later becomes concentrated beneath the lamina.

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Mucolipidosis Type III α/β: The First Characterization of This Rare Disease by Autopsy

Archives of Pathology & Laboratory Medicine ◽

10.5858/2010-0236-cr.1 ◽

2011 ◽

Vol 135 (4) ◽

pp. 503-510

Author(s):

Darcy A Kerr ◽

Vincent A Memoli ◽

Sara S Cathey ◽

Brent T Harris

Keyword(s):

Electron Microscopy ◽

Heart Valves ◽

Light And Electron Microscopy ◽

Lysosomal Storage ◽

Cytoplasmic Granules ◽

Type Iii ◽

Mucolipidosis Type ◽

Electron Lucent ◽

And Cartilage

Abstract We report findings from an autopsy of a 45-year-old woman with the rare lysosomal storage disease mucolipidosis type III α/β. Her disease manifested most notably as multiple bone and cartilage problems with tracheal and bronchial malacia. Principal autopsy findings included gross abnormalities in bone and cartilage with corresponding microscopic cytoplasmic lysosomal granules. These cytoplasmic granules were also seen in histologic preparations of the brain, myocardium, heart valves, and fibroblasts of the liver and skin by light and electron microscopy. By electron microscopy there were scattered, diffuse vesicular cytoplasmic granules in neurons and glia and an increase in lysosomal structures with fine electron lucent granularity in the above tissue types. Our findings help elaborate current understanding of this disease and differentiate it from the mucopolysaccharidoses and related disorders. To our knowledge, this is the first report to document pathologic findings in a patient with mucolipidosis type III α/β by autopsy.

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Characterization of Endocytic Pathways by Quantitative Fluorescence Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927600025241 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 1024-1025

Author(s):

Frederick R. Maxfield ◽

Richik N. Ghosh ◽

William G. Mallet ◽

Thwe Thwe Soe ◽

Philip L. Leopold ◽

...

Keyword(s):

Electron Microscopy ◽

Cell Surface ◽

Light And Electron Microscopy ◽

Endocytic Pathway ◽

Early Endosomes ◽

Pass Through ◽

Golgi Network ◽

Quantitative Fluorescence ◽

Endocytic Pathways

We have used light and electron microscopy to analyze endocytic trafficking pathways. In one set of studies, we have used fluorescently labeled antibodies to trace an endocytic pathway from the cell surface to the trans- Golgi network (TGN). Cells were transfected with a construct consisting of the transmembrane and cytoplasmic domains of TGN38 and the extracellular domain of Tac. TGN38 is predominantly in the TGN, but a small fraction is found on the cell surface. We used FITC-labeled anti-Tac monoclonal IgG to analyze the pathway from the surface to the TGN. We compared the distribution of internalized Tac-TGN38 to internalized transferrin. We found that most Tac-TGN38 enters the same early endosomes as transferrin. Furthermore, most Tac-TGN38 returns to the cell surface from the endocytic recycling compartment (ERC) at the same rate as transferrin. However, on each pass through the cell approximately 18% of Tac-TGN is retained, and this Tac-TGN38 is delivered to the TGN.

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Characterization of Photochemically Induced Spinal Cord Injury in the Rat by Light and Electron Microscopy

Experimental Neurology ◽

10.1006/exnr.1994.1082 ◽

1994 ◽

Vol 127 (1) ◽

pp. 76-93 ◽

Cited By ~ 72

Author(s):

Mary Bartlett Bunge ◽

Vicky R. Holets ◽

Margaret L. Bates ◽

Theresa S. Clarke ◽

Brant D. Watson

Keyword(s):

Electron Microscopy ◽

Spinal Cord ◽

Spinal Cord Injury ◽

Light And Electron Microscopy ◽

Cord Injury

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Production and characterization of monoclonal antibodies to the sapstaining fungus Ophiostoma piceae

Canadian Journal of Microbiology ◽

10.1139/m94-006 ◽

1994 ◽

Vol 40 (1) ◽

pp. 35-44 ◽

Cited By ~ 6

Author(s):

Srabani Banerjee ◽

Judy Little ◽

Maria Chan ◽

Brian T. Luck ◽

Colette Breuil ◽

...

Keyword(s):

Electron Microscopy ◽

Cell Wall ◽

Monoclonal Antibodies ◽

Light And Electron Microscopy ◽

Cross Reactivity ◽

Cell Wall Protein ◽

Enzyme Linked Immunosorbent Assay ◽

Enzymatic Modification ◽

Ophiostoma Piceae

A sensitive immunological tool has been developed to detect the sapstaining fungus Ophiostoma piceae 3871, which plagues the wood industry. Monoclonal antibodies (1F3(1), 4G3(14), 4G2(4), and 2B6(24)) produced against cell wall protein extracts of this fungus were specific. Specificity was estimated by enzyme linked immunosorbent assay, western blotting, and light and electron microscopy using the immunogold technique. Electron microscopy revealed gold particles localized on the outer surface of the cell wall. When screened against 24 biological control fungi the antibodies showed pratically no cross-reactivity (< 4%). When tested against 19 other staining fungi, the antibodies recognized three strains of Ophiostoma piceae, 1F3(1) recognized Phialophora botulispora, and the antibodies showed less than 5% reactivity with the other fungi. Chemical and enzymatic modification of the antigen revealed that the epitopes recognized by the monoclonal antibodies were glycospecific. Although the antibodies were produced against the cell wall protein extracts of the fungus grown in liquid culture, they also recognized the fungus growing in wood and therefore can be employed to investigate wood colonization by this fungus.Key words: Ophiostoma piceae, monoclonal antibodies, glycoprotein.

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