Related Experiment Videos
Selective extraction of isolated mitotic apparatus. Evidence that typical microtubule protein is extracted by organic
Abstract:
Mitotic apparatus isolated from sea urchin eggs has been treated with meralluride sodium under conditions otherwise resembling those of its isolation. The treatment causes a selective morphological disappearance of microtubules while extracting a major protein fraction, probably consisting of two closely related proteins, which constitutes about 10% of mitotic apparatus protein. Extraction of other cell particulates under similar conditions yields much less of this protein. The extracted protein closely resembles outer doublet microtubule protein from sea urchin sperm tail in properties considered typical of microtubule proteins: precipitation by calcium ion and vinblastine, electrophoretic mobility in both acid and basic polyacrylamide gels, sedimentation coefficient, molecular weight, and, according to a preliminary determination, amino acid composition. An antiserum against a preparation of sperm tail outer doublet microtubules cross-reacts with the extract from mitotic apparatus. On the basis of these findings it appears that microtubule protein is selectively extracted from isolated mitotic apparatus by treatment with meralluride, and is a typical microtubule protein.
Insights
Meralluride sodium selectively extracts microtubule protein from sea urchin egg mitotic apparatus. This protein shares characteristics with outer doublet microtubule protein from sperm tails.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- The mitotic apparatus is crucial for cell division.
- Microtubules are key components of the mitotic spindle.
- Understanding microtubule protein composition is vital for cell biology research.
Purpose of the Study:
- To investigate the effect of meralluride sodium on isolated mitotic apparatus.
- To identify and characterize the protein fraction selectively extracted by meralluride sodium.
- To determine if the extracted protein is typical microtubule protein.
Main Methods:
- Isolation of mitotic apparatus from sea urchin eggs.
- Treatment of isolated mitotic apparatus with meralluride sodium.
- Biochemical and biophysical characterization of the extracted protein fraction.
- Immunological cross-reactivity assays using antiserum against sperm tail microtubule protein.
Main Results:
- Meralluride sodium treatment caused selective disappearance of microtubules.
- A major protein fraction (approx. 10% of total protein) was extracted.
- The extracted protein exhibited properties typical of microtubule proteins, including calcium and vinblastine precipitation, electrophoretic mobility, sedimentation coefficient, molecular weight, and amino acid composition.
- Antiserum against sperm tail outer doublet microtubules cross-reacted with the extracted protein.
Conclusions:
- Meralluride sodium selectively extracts a major protein fraction from isolated mitotic apparatus.
- The extracted protein is identified as a typical microtubule protein.
- This finding provides insights into the composition and dynamics of the mitotic spindle microtubules.