Figure 4

Dot blot assay to estimate the copy number of Gamera. Five strips of nylon membranes were blotted with medaka fish genomic DNA of different concentrations, indicated in the left margin. The strips were, separately but under the same conditions, hybridized with the probes indicated at the top. Tol2 is a multi-copy DNA-based transposable element and its copy number per diploid genome of the fish used had been estimated to be exactly 34 by the method described in Koga et al (2000). Dots exhibiting nearly the same intensities were selected as indicated by the lines, and the copy numbers for probes a to d were estimated by using the copy number of Tol2 as the standard. The estimated copy numbers per diploid genome are shown at the bottom. All the five probes were 800–900 bp in length. The region used for the Tol2 probe is nucleotides 575-1392 of EMBL D84375. For Gamera probes a to d, see legend to Figure 1.