Chemical labeling strategies for cell biology

Planktonic foraminifera are widely-distributed and abundant zooplankters. They are significant as water mass indicators and provide evidence of paleotemperatures and events which occurred during Pleistocene glaciation. In spite of their ecological and paleological significance, little is known of their cell biology. There are few cytological studies of these organisms at the light microscope level and some recent reports of their ultrastructure.Specimens of Globigerinoides ruber, Globigerina bulloides, Globigerinoides conglobatus and Globigerinita glutinata were collected in Bermuda waters and fixed in a cold cacodylate-buffered 6% glutaraldehyde solution for two hours. They were then rinsed, post-fixed in Palade's fluid, rinsed again and stained with uranyl acetate. This was followed by graded ethanol dehydration, during which they were identified and picked clean of debris. The specimens were finally embedded in Epon 812 by placing each organism in a separate BEEM capsule. After sectioning with a diamond knife, stained sections were viewed in a Philips 200 electron microscope.

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Introduction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070266 ◽

1978 ◽

Vol 36 (3) ◽

pp. 543-544

Author(s):

W. Bernard

Keyword(s):

Molecular Weight ◽

Electron Microscope ◽

Nucleic Acid ◽

Gene Mapping ◽

Molecular Genetics ◽

Cell Biology ◽

Gene Activity ◽

Close Connection ◽

Basic Information ◽

Simple Systems

In comparison to many other fields of ultrastructural research in Cell Biology, the successful exploration of genes and gene activity with the electron microscope in higher organisms is a late conquest. Nucleic acid molecules of Prokaryotes could be successfully visualized already since the early sixties, thanks to the Kleinschmidt spreading technique - and much basic information was obtained concerning the shape, length, molecular weight of viral, mitochondrial and chloroplast nucleic acid. Later, additonal methods revealed denaturation profiles, distinction between single and double strandedness and the use of heteroduplexes-led to gene mapping of relatively simple systems carried out in close connection with other methods of molecular genetics.

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Application of FRAP and digitized fluorescence microscopy to problems in cell membrane dynamics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102675 ◽

1988 ◽

Vol 46 ◽

pp. 118-119

Author(s):

K. Jacobson ◽

A. Ishihara ◽

B. Holifield ◽

F. Zhang

Keyword(s):

Fluorescence Microscopy ◽

Cell Biology ◽

Extended Period ◽

Dynamic Structure ◽

Living Cells ◽

Membrane Dynamics ◽

Molecular Cell Biology ◽

Image Averaging ◽

Single Living Cells ◽

Single Living

Our laboratory is concerned with understanding the dynamic structure of the plasma membrane with particular reference to the movement of membrane constituents during cell locomotion. In addition to the standard tools of molecular cell biology, we employ both fluorescence recovery after photo- bleaching (FRAP) and digitized fluorescence microscopy (DFM) to investigate individual cells. FRAP allows the measurement of translational mobility of membrane and cytoplasmic molecules in small regions of single, living cells. DFM is really a new form of light microscopy in that the distribution of individual classes of ions, molecules, and macromolecules can be followed in single, living cells. By employing fluorescent antibodies to defined antigens or fluorescent analogs of cellular constituents as well as ultrasensitive, electronic image detectors and video image averaging to improve signal to noise, fluorescent images of living cells can be acquired over an extended period without significant fading and loss of cell viability.

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Correlative microscopy in distrubuted (client/server) computing environments: tools for catalyzing the rapid dissemination of information about the cell biology of the human prostate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139780 ◽

1995 ◽

Vol 53 ◽

pp. 682-683

Author(s):

A. Hakam ◽

J.T. Gau ◽

M.L. Grove ◽

B.A. Evans ◽

M. Shuman ◽

...

Keyword(s):

United States ◽

Cell Biology ◽

Tissue Bank ◽

The United States ◽

Prostate Adenocarcinoma ◽

Correlative Microscopy ◽

Client Server ◽

Critical Elements ◽

Transplant Organ

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.

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Defects of Platelet Function Recognized by X-Ray Imaging and Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119806 ◽

1985 ◽

Vol 43 ◽

pp. 610-613

Author(s):

M.G. Baldini ◽

S. Morinaga ◽

D. Minasian ◽

R. Feder ◽

D. Sayre ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Biology ◽

Imaging Technique ◽

Human Platelets ◽

X Rays ◽

X Ray ◽

X Ray Imaging ◽

Complex Phenomena ◽

Scanning Electron

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).

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Exploration of cell wall architecture with the rapid-freeze deep-etch technique

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146485 ◽

1993 ◽

Vol 51 ◽

pp. 128-129

Author(s):

Béatrice Satiat-Jeunemaitre ◽

Chris Hawes

Keyword(s):

Plant Cell ◽

Cell Walls ◽

Cell Biology ◽

Molecular Model ◽

Three Dimensional ◽

Secretory Activity ◽

Wall Structure ◽

Specimen Preparation ◽

Molecular Architecture ◽

Plant Cell Walls

The comprehension of the molecular architecture of plant cell walls is one of the best examples in cell biology which illustrates how developments in microscopy have extended the frontiers of a topic. Indeed from the first electron microscope observation of cell walls it has become apparent that our understanding of wall structure has advanced hand in hand with improvements in the technology of specimen preparation for electron microscopy. Cell walls are sub-cellular compartments outside the peripheral plasma membrane, the construction of which depends on a complex cellular biosynthetic and secretory activity (1). They are composed of interwoven polymers, synthesised independently, which together perform a number of varied functions. Biochemical studies have provided us with much data on the varied molecular composition of plant cell walls. However, the detailed intermolecular relationships and the three dimensional arrangement of the polymers in situ remains a mystery. The difficulty in establishing a general molecular model for plant cell walls is also complicated by the vast diversity in wall composition among plant species.

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