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Published on: September 24, 2015
Characteristics of the nucleolini observed under the electron microscope
Experientia
|June 15, 1976
Summary
Electron microscopy revealed that nucleolini in molluscs, echinoderms, and tumor cells are "clear fibrillar zones." These zones contain thin fibrils within a clear matrix, surrounded by thicker, interlacing fibrils.
Area of Science:
- Cell Biology
- Microscopy
- Histology
Background:
- Nucleolini are structures previously observed in oocytes and tumor cells using light microscopy.
- The precise ultrastructure and composition of nucleolini have remained unclear.
Purpose of the Study:
- To elucidate the ultrastructural characteristics of nucleolini in molluscs and echinoderm oocytes, and malignant tumor cells.
- To correlate light microscopic observations of nucleolini with their electron microscopic appearance.
Main Methods:
- Electron microscopy was employed to examine the ultrastructure of nucleolini.
- Comparative analysis was performed on oocytes from molluscs and echinoderms, and malignant tumor cells.
Main Results:
- Electron microscopy identified nucleolini as "clear fibrillar zones" within the observed cells.
- These zones are characterized by 40-60 Å thick fibrils dispersed in a clear matrix.
- A surrounding layer of thickened, interlacing fibrils was consistently observed around the clear fibrillar zones.
Conclusions:
- The "clear fibrillar zones" observed via electron microscopy represent the ultrastructural correlate of nucleolini seen with light microscopy.
- This finding provides a detailed ultrastructural understanding of nucleolini in diverse cell types.
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