Fig. 2.

ms771 maps to nutcracker (CG10855), which encodes an uncharacterized F-box protein expressed in testes. (A) nutcracker genomic region. nutcracker is located at position 63F1, within the region removed by the deficiency Df(3L)Exel6097. Two piggyback insertions (inverted triangles) are annotated for nutcracker: PBac{WH}CG10855^f03797 is inserted upstream of the ATG start site, and PBac{WH}CG10855⁰⁷²⁵⁹ (nutcracker⁰⁷²⁵⁹) is inserted in the intronic region. An orange star indicates the location of the premature stop codon mutation in nutcracker^ms771 that results in the truncation of the F-box domain. (B) The ms771 mutation maps to nutcracker. The deficiency Df(3L)Exel6097 fails to complement ms771 sterility and staining, and both these defects are rescued by reintroducing nutcracker ORF. nutcracker⁰⁷²⁵⁹ also has individualization defects and is hypomorphic for Caspase-3 staining. The staining is slightly reduced, but not eliminated, in the transheterozygote nutcracker^ms771/07259. (C) The F-box protein Nutcracker shares sequence homology with the F-box-only protein FBXO7. Alignment of the Drosophila Nutcracker protein against human FBXO7 (accession number CAG30377). The proteins exhibit highest similarity in their F-box domains. Overall, they share 17 identical amino acids (5% of Nutcracker, 2% of FBXO7), and 36 similar amino acids (11% of Nutcracker, 7% of FBXO7). Not shown are the last ~100 amino acids of FBXO7, as it is a longer protein.