FishScope Developmental Landmarks

Developmental Landmarks

These time-lapse recordings illustrate the morphogenesis of Zebrafish embryos, from early cleavage to organ rudiment formation.

The following links take you to movie descriptions and download options.

4-cell stage movie: Showing cycles of nuclear membrane breakdown, spindle dynamics, cytokinesis, and yolk platelet motility.
16-cell stage movie: Showing spindle dynamics, yolk platelet motility, and cytoplasmic streaming between the yolk cell and marginal blastomeres of the blastoderm.
Formation of the cellularized blastoderm movie: Showing asynchronous cell divisions and the formation of the yolk syncytial layer.
Onset of epiboly, formation of the epiblast and hypoblast movie: Showing the onset of epiboly, involution of the germ ring, and convergence of deep cells to the inner layer of the hypoblast.
Onset of epiboly (More detailed movie): Involution of cells forms the germ ring, migrations of deep cells involved in the formation of the hypoblast.
Embryonic shield formation movie: Showing an animal pole view, radial intercalation of blastomeres, formation of the hypoblast, convergence of deep cells towards the embryonic axis (migration to the northeast), and appearance of the head anlage.
Notochord formation movie: Showing convergence and extension among cells in the chordamesoderm, formation of the notochord, segmentation in the paraxial mesoderm (formation of somites), and convergence and compaction of the somites.
Somitic segmentation and amoeboid cells in movie: Showing oriented cell divisions in the neuroectoderm, mediolateral convergence of neuroectodermal cells involved in neural keel formation (3 somite stage embryo).
Neural plate movie: Begins with a focus through (2 stills) from the level of the notochord (3-somite stage) to the dorsally located neuroectoderm, then focuses on the transformation of the neural plate into the neural keel.
Blastopore closure movie: Begins at the focal plane of the enveloping layer. Focal plane shifts to the blastoderm margin. Cellular mechanics involved in blastopore closure.
Floorplate movie: Begins at the level of the axial hypoblast, shows mediolateral intercalation of cells in the chorda mesoderm. Neuroectodermal cells in the epiblast converge towards the embryonic midline and depress the notochord to a more ventral position. Oriented cell divisions at the level of the floorplate. Observation of the otic placode, the developing ear rudiment.

For detailed descriptions of Zebrafish morphogenesis, consult The Zebrafish Book by M. Westerfield of the University of Oregon.

last updated 3/21/00 (JAR)