Figure 4. Positional Cloning of the dre Mutant.

(A) Schematic representation of assembled contig 11890 of the Zv2 genome assembly. SSLP markers z5395 and z25745 and newly identified SSLPs 11890.2A and 11890.2 were closely linked with the dre locus. Remaining recombinants of a complete panel of 765 mutant embryos are indicated. Four genes were predicted in the region of marker 11890.2A that encode Su(fu), TRC8, ubiquitin conjugating enzyme E2, and β-mannosidase precursor protein.

(B) The dre mutation is a C to an A substitution, changing a threonine to a lysine.

(C) Multiple alignment of Su(fu) homologs revealed that the induced mutation changes an amino acid in a highly conserved region of Su(fu).