GVBD and migration of the meiotic apparatus towards the cell cortex in a dechorionated oocyte of Ciona .The light zone corresponding to the meiotic apparatus is formed in the center of the oocyte and migrates upward to the cortex over a 2 hour period. DIC optics.
Prodon et al. (2006) Dev.Biol, 290, 297-311 PDF

Polarity of the endoplasmic reticulum (ER) network in a mature Ciona oocyte.
Confocal z sections of an oocyte whose ER is labelled with a droplet of DiIC16(3) injected into the oocyte. Images were acquired at 1 µm intervals from the surface to the equator. The vegetal pole is on the lower left.
Prodon et al. (2005) J.Cell Science, 119, 1592-1603 PDF

Cortical endoplasmic reticulum (cER) network under the surface of a mature Ciona oocyte.
Transition zone between the animal (upper right) and vegetal(lower left) hemispheres showing the distribution of mitochondria (green) and ER (red) under the surface . Sequential confocal z sections were acquired at 0.5µm intervals.
Prodon et al. (2005) J.Cell Science, 119, 1592-1603 PDF

ER network and microtubules in an solated cortical fragment from a mature Phallusia oocyte.
The fluorescent images show alternately the cER network (labelled with DiOC(6)3) and microtubules (labelled with antitubulin antibody) in a fixed cortical fragmant. ER tubes and sheets are most abundant on the vegetal side (left). The second part of of the film shows a high resolution DIC image of a live cortical fragment in which a part of the cER network is attached to the underlying plasma membrane.
Sardet et al. (1992) Development, 115, 221-237. PDF

From fertilization to first cleavage in Phallusia.
Fertilization triggers a cortical contraction and meiosis completion. A transient contraction pole is formed (on left) followed by the emission of a first polar body (on right), meiotic oscillations and then emisson of the second polar body. Migration of male and female pronuclei follows. Large rotational movements of the posterior cytoplasm (top) with respect to the cortex take place after the pronuclei meet(DIC optics). Spindle formation and mitosis are then imaged using polarization optics and cleavage occurs at 60 minutes after fertilization. Time lapse sequence (DIC and polarized microscopy) recorded with S Inoue, L Jaffe and J.E.Speksnijder, speeded up 150 times.
Sardet, C., et al. (1989). Development 105, 237-249 PDF

Fertilization, contraction and reorganization of the cortical endoplasmic reticulum (cER) domain in Phallusia.
Here the continuous ER network in the egg is labelled with injected DiIC(16)3 (white). The actomyosin-driven cortical contraction triggered by the fertilization calcium wave leads to concentration of both the cER and the adjacent ER-poor mitochondria-rich myoplasm in the vegetal/contraction pole (bottom). After contraction, the egg undergoes repetitive contractions or pulses which correspond to meiotic oscillations. Time lapse confocal microscopy of a single equatorial section, speeded up 10 times.
Speksnijder J.E., et al. (1993) J. Cell Biol. 120, 1337-1346 PDF

Meiotic contractions, Vegetal Button formation, and the second major phase of reorganization (Phallusia).
The sequence corresponds to the period between the end of Meiosis I (10 minutes after fertilization) and first cleavage ( 60 minutes after fertilization). Observe: periodic contractions, second polar body formation (upper right), vegetal button protrusion ( lower left), the meeting of male and female pronuclei, and a large translocation corresponding to the second major phase of reorganization. Posterior is up. Time lapse DIC microscopy : this sequence is speeded up 100 times
Sardet C., et al. (1989). Development, 105, 237-249 PDF
Roegiers et al. (1999).   Development, 126, 3101-3117. PDF

The ER network at the time of the second major phase of reorganization (Phallusia).
A fertilized egg whose ER network is labelled with DiIC16(3) (white) . The bright spot at the top is the site of injected DiI. Five series of confocal z sections were acquired at one minute intervals over the period 30-35 minutes after fertilization. The cER network (bottom part of the image) translocates towards the sperm aster (left part of the image) .
Speksnijder J.E., et al. (1993) J. Cell Biol. 120, 1337-1346 PDF

Reorganizations of ER network (red) and mitochondria-rich myoplasm (green) in Phallusia.
This film covers the period from fertilization to mitosis. It shows - the first major phase of reorganization (contraction concentrating myoplasm and cER vegetally) - the second major phase of reorganization (posterior translocation of the bulk of myoplasm and cER). The animal pole is in the upper right corner, posterior is left. The bright red droplet corresponds to the site of injection for DiIC16 (3) to label ER (red). Time-lapse confocal sequence(equatorial sections) .
Prodon et al. (2005) J.Cell Science 119, 1592-1603. PDF

Surface movements after meiosis and before first cleavage (Phallusia).
The egg was labelled on its surface with nile blue particules. The film starts just after meiosis completion. Note the transient appearance of the vegetal button (lower left)and the surface relaxation wave which spreads surface particles over the vegetal region between mitosis and first cleavage. DIC time lapse microscopy.
Roegiers et al. (1999) Development 126, 3101-3117. PDF

Asymmetric cleavage in posterior blastomeres of 16 cell stage embryo (Phallusia).
In the first part of the film the centrosome can be observed as a clear zone in front of the interphase nucleus . Led by the centrosome, the nucleus stretches and migrates near the posterior cortex. In the second part of the movie (from 11 seconds), the nuclei are already positioned near the cortex. After nuclear breakdown two CABs are visible as a smooth moustache-shaped zone. One spindle pole in each cell approaches the CAB and unequal cleavage ensues. DIC time lapse microscopy. Frames were collected every 10 seconds and are displayed at a rate of 30 per second.
Patalano et al. (2006) J.Cell Science, 119, 1592-1603. PDF

Asymmetric cleavages in posterior blastomeres (Phallusia).
The film shows divisions of the posterior pair of cells as the embryo passes from the 8 to the 32 cell stages. ER is labeled with DiIC16 (3) (red) and mitochondria with DiOC2(3) (green). Arrow shows the cER-rich CABs. Time-lapse sequence of a single confocal plane. Images were acquired every 2 minutes.
Prodon et al. (2005) J. Cell Science, 118, 2393-2404. PDF

Multilayerd structure of the Centrosome Attracting Body (CAB) (Phallusia).
Posterior blastomeres of a 16 cell embryo fixed and labelled for aPKC polarity protein (green) and mitochondria (red). Sequential confocal z sections show the unlabelled space occupied by the cER/mRNA domain between the cortical patch of aPKC and the mitochondria-rich myoplasm.
Patalano et al. (2006) J.Cell Science, 119, 1592-1603. PDF

aPKC protein and microtubules in the CAB region (Phallusia).
This B4.1 blastomere in prophase is part of an 8-cell stage embryo which has been fixed and labelled for aPKC(green) and microtubules (red) . Plus ends of microtubules contact the cell surface at the aPKC-rich domain in the CAB and also reach cortical regions adjacent to the CAB. The film traverses the blastomere via confocal z sections at intervals of 0.4 µm.
Patalano et al. (2006) J.Cell Science, 119, 1592-1603. PDF

aPKC particles in the CAB (Phallusia).
An 8 cell embryo fixed and labelled for aPKC (green). The film shows sequential confocal z sections 1.2 microns apart of the posterior vegetal surface of B4.1 blastomeres (posterior view) . aPKC-rich particles line the blastomere surface and are densely packed at the position of the CABs. The field measures 45 µm on each side.
Patalano et al. (2006) J.Cell Science, 119, 1592-1603. PDF

Development from egg to tadpole in 12 hours (Phallusia).
Mitochondria-rich myoplasm domain (labelled with DIOC2(3) (green) is partitioned into the posterior pair of blastomeres which give rise to primary muscle cells in the tail of the tadpole . Time lapse DIC and fluorescence microscopy.