Genotyping and verifying mpx-null zebrafish larvae.

A) Diagram of a WT (mpx^wt) and mutated (mpx^NL144) gene, showing the BtsCI restriction site cutting only the mutated mpx^NL144 gene. B) PCR amplification of the mpx gene from the genomic DNA of mpx^wt, mpx^wt/NL144 and mpx^NL144 fish–fragment 312bp; control DNA is a positive control from a separate genotyping experiment. Hyperladder 1kb. C) Diagnostic digest of the PCR product from mpx^wt, mpx^wt/NL144 and mpx^NL144 fish. Band sizes: mpx^wt- 312bp, mpx^NL144- 230bp, mpx^wt/NL144- 312bp and 230bp. Hyperladder 100bp plus. D) DNA sequencing of the PCR products to confirm the accuracy of the BtsCI digest. E) mpx^wt, mpx^NL144 and mpx^wt/NL144 larvae fixed at 4dpf and stained with Sudan Black B. Larvae with at least one functional mpx allele stained (57/58 mpx^wt, 20/20 mpx^wt/NL144) and larvae that do not produce Mpx did not stain (32/32 mpx^NL144). Inset shows an enlarged view of the region indicated by the dashed white box. Scale bar = 200μm.