Cell lineage analysis in ascidian embryos by intracellular injection of a tracer enzyme: III. Up to the tissue restricted stage

doi:10.1016/0012-1606(87)90188-6

Developmental Biology

Volume 121, Issue 2, June 1987, Pages 526-541

https://doi.org/10.1016/0012-1606(87)90188-6 Get rights and content

Abstract

Cell lineages during embryogenesis of the ascidian Halocynthia roretzi were analyzed up until the stage where each blastomere was fated to be only a single tissue type (i.e., the tissue restricted stage) by intracellular injection of horseradish peroxidase using the iontophoretic injection method. Initially, the developmental fates of all blastomeres of the 64-cell stage embryo were examined, and thereafter, only the fates of daughter blastomeres of those blastomeres that were not tissue restricted at the 64-cell stage were traced. The developmental fates of blastomeres were highly invariant except for two candidates for “equivalence groups” (J. Kimble, J. Sulston, and J. White (1979). In “Cell Lineage, Stem Cells and Cell Determination,” pp. 59–68. Elsevier, Amsterdam/New York), in which cellular interaction is suggested to be involved in the specification of the fates. The right and left a8.25 cells gave rise to the otolith and ocellus, and the right and left b8.17 cells gave rise to the spinal cord and endodermal strand in a complementary manner. No fixed relationship existed between the position of the blastomere and its derivative. Most restrictions of cell fates occurred early in cleavage. The numbers of blastomeres which generated a single type of tissue were 44 at the 64-cell stage and 94 at the 110-cell stage. Eight pairs of blastomeres had not yet become tissue restricted by the 110-cell stage. Almost complete lineages of epidermis, nervous system, muscle, mesenchyme, notochord, and endodermal tissues were described, and a fate map was constructed for the blastula. For certain tissues, the primordial cells occupied two different regions. Supplementary investigations of the lineage of muscle cells were also performed on embryos of another species, Ciona intestinalis.

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^☆: This work was supported in part by a Grant-in-Aid from the Ministry of Education, Science and Culture of Japan (60105001) to Dr. N. Satoh.

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Full paperCell lineage analysis in ascidian embryos by intracellular injection of a tracer enzyme: III. Up to the tissue restricted stage☆

Abstract

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The early embryology of Ciona intestinalis, Flemming (L.)

Bull. Mus. Comp. Zool

Larval adhesive organs and metamorphosis in ascidians

Cell Tissue Res

The organization and cell lineage of the ascidian egg

J. Acad. Nat. Sci. (Philadelphia)

Full paper
Cell lineage analysis in ascidian embryos by intracellular injection of a tracer enzyme: III. Up to the tissue restricted stage☆