Fig. 5

Injection of pitx3 morpholino results in abnormal splicing of pitx3 transcript and small lens phenotype.

A. Schematic drawing of pitx3 gene; position of initiation codon (ATG) and RT-PCR primers (1F and 3R) are indicated, exons are numbered. B. Sequencing of the pitx3-mo transcript generated with primers located in the first and third pitx3 exons demonstrates absence of exon 2 in the resultant product. C. RT-PCR results obtained with pitx3 1F/3R primers using RNA extracted from embryos injected with control or pitx3 morpholino. Please note a strong decrease in normal 276-bp product (black arrowhead) and presence of abnormal 148-bp product (red arrowhead) in pitx3-mo samples; hpf- hours post fertilization of analyzed embryos. D–G. Morphological phenotypes of zebrafish pitx3-mo embryos. In comparison to control embryos, a smaller head can be observed in pitx3 morphants (72-hpf embryo is shown; D) as well as an obvious reduction in lens size (black arrow) at later stages (96-hpf embryos are shown; E–G). H and I. Expression of pitx3 in the developing lens in 24-hpf embryos. Please note robust expression in the lens vesicle (arrows) as demonstrated by both whole mount (H) and section (I) in situ.