Proviral insertions in the zebrafish hagoromo gene, encoding an F-box/WD40-repeat protein, cause stripe pattern anomalies

The zebrafish, Danio rerio, has three types of pigment cells (melanophores, xanthophores and iridophores) and, in adult fish, these cells are organize d into a stripe pattern. The mechanisms underlying formation of the stripe pattern are largely unknown. We report here the identification and characte rization of a novel dominant zebrafish mutation, hagoromo (hag), which was generated by insertional mutagenesis using a pseudotyped tetrovirus. The ha g mutation caused disorganized stripe patterns. Two hag mutant alleles were isolated independently and proviruses were located within the fifth intron of a novel gene, which we named hag, encoding an F-box/WD40-repeat protein . The hag gene was mapped to linkage group (LG)13, close to fgf8 and pax2.1 . Amino acid sequence similarity, conserved exon-intron boundaries and cons erved synteny indicated that zebrafish hag is an ortholog of mouse Dactylin , the gene mutated in the Dactylaplasia (Dac) mouse [1]. The Dac mutation i s dominant and causes defects in digit formation in fore- and hindlimbs. Th is study revealed that the hag locus is important for pattern formation in fish but is involved in distinct morphogenetic events in different vertebra tes.