Fig. 1

Identification and characterization of a splice-donor mutation in the zebrafish ptc1 gene. A splice donor mutation was identified in the first base pair of intron 10, changing the consensus sequence GT to AT, probably affecting splicing (A). The intron after exon 10, shown in lower case in yellow, contains 81 bp, and the splice donor position mutated in ptc1^hu1602 is indicated in red (B). RT-PCR analysis confirms that splicing is affected as a result of the mutation, which extends the transcript with 81 bp compared to wild type (C). Schematic representation of the Ptc1 protein, showing the 12 transmembrane domains (black dots), and the extension of the second extracellular loop with 27 AA in red. The blw mutation is positioned directly after the eighth transmembrane domain of the protein (D).