Fig. 2

Duplicated 4.1B genes are differentially expressed in the zebrafish trunk.

(A) Analysis of 4.1B expression levels during various stages of development. 4.1Ba and 4.1Bb are expressed throughout development. From left to right, cDNA samples were derived from wild-type (AB/Tübingen) zebrafish at the 16-cell (1.5 hpf), 90% epiboly (9 hpf), 3-somite (11 hpf), 16-, 24-, 48-, 72 hpf, and 7 days post fertilization (dpf) stages. (B) in situ hybridization showing 4.1Ba and 4.1Bb expression in the brain and trunk of the developing zebrafish embryo at 26 hpf. Both 4.1Ba and 4.1Bb are expressed in the telencephalon (Te), the mesencephalon (Me), and retina (Rt). Only 4.1Bb was seen in muscle (Mu). (C) Cross section of the trunk at 26 hpf further demonstrates only 4.1Ba is expressed in the spinal cord (dotted ellipse), whereas 4.1Bb is expressed in muscle. (D—G) Fluorescent in situ hybridization of the trunk confirming expression of 4.1Ba, but not 4.1Bb in CaPs (E) and CoPA cells (F), and 4.1Bb, but not 4.1Ba, in muscle (G) at 26 hpf. White boxes in D indicate cells shown in E. Scale Bar in B: 500 μm; C: 100 μm; D: 20 μm; E, F: 5 μm; G: 50 μm; Abbreviations: bg = background from chicken anti-GFP antibody.