Amphioxus embryos

The protocol given is designed for amphioxus embryos and larvae, obtained as described in Chapter 38. The method is modified from ref. 1 and has been used to visualize RNA from several developmentally expressed genes of amphioxus (see Note 1). With modification, it has also been successfully appUed to... 

Mount embryos on slides in 80% glycerol in PBT. For amphioxus embryos, support the coverslip with strips of autoclave tape stuck onto the slide. 

Holland, L. Z., and N. D. Holland. 1996. Expression of Amphihox-1 and Amphipax-1 in Amphioxus Embryos Treated with Retinoic Acid Insights into Evolution and Patterning of the Chordate Nerve Cord and Pharynx. Development 122, no 6 1829-38. 

Extracellular matrix. The matrix gfyco HX)teins appeared first in the amphioxus and ciona. In vertebrate mammalian embryos, tenascins (TNs, distinguish from same abbreviation for triple negatives) are abundantly expressed, but in adult life retreat to moderate restricted appearance. In malignantly transformed tissues TNs resume their abundant expression. In single cells, TNs expression inhibits amoeboid movement. TNs-coated glioblastoma cells inhibit amoeboid movement of T lymphocytes ovta- the cell surface. ... 

Here we give protocols for obtaining embryos and larvae of one ascidian species, Ciona intestimlis, and one amphioxus species, Branchiostoma floridae. 

Koop, D., and L. Z. Holland. 2008. The Basal Chordate Amphioxus as a Simple Model for Elucidating Developmental Mechanisms in Vertebrates. Birth Defects Res C Embryo Today 84, no 3 175-87. 

Figure 2.5 Developmental expression of BMP2I4 and homologs of neural crest markers in amphioxus. Cross sections through early neurula. Expression for each gene is shown for one side of the embryo only, (a) Left side of embryo. Dll and Snail. Right side of embryo, PaxlH. (b) Left side of embryo, Msx. Right side of embryo, BMP2/4.

Langeland, J.A., Tomsa, J.M., Jackman, W.R. and Kimmel, C.B. (1998) An amphioxus snail gene expression in paraxial mesoderm and neural plate suggests a conserved role in patterning the chordate embryo . Development Genes and Evolution, 208, 5G9-77. 

Figure 3.1 Schematic diagrams showing the dorsoventral expression patterns of HNF-3, hh, Pax-3/7 and Msx gene homologues in the notochord and forming neural tube of amphioxus and/or ascidian embryos. Not all genes are expressed at the same stages of development or with the same intensity. D, dorsal region of neural tube V, ventral FP, floorplate N, notochord.

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