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Updated: Aug 7, 2026

Xenopus laevis Egg Extract Preparation and Live Imaging Methods for Visualizing Dynamic Cytoplasmic Organization
Published on: June 6, 2021
Changes in organization of the endoplasmic reticulum during Xenopus oocyte maturation and activation
M Terasaki1, L L Runft, A R Hand
1Department of Physiology, University of Connecticut Health Center, Farmington 06032, USA. terasaki@neuron.uchc.edu
Abstract:
The organization of the endoplasmic reticulum (ER) in the cortex of Xenopus oocytes was investigated during maturation and activation using a green fluorescent protein chimera, immunofluorescence, and electron microscopy. Dense clusters of ER developed on the vegetal side (the side opposite the meiotic spindle) during maturation. Small clusters appeared transiently at the time of nuclear envelope breakdown, disappeared at the time of first polar body formation, and then reappeared as larger clusters in mature eggs. The appearance of the large ER clusters was correlated with an increase in releasability of Ca(2+) by IP(3). The clusters dispersed during the Ca(2+) wave at activation. Possible relationships of ER structure and Ca(2+) regulation are discussed.
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