Fig. 1
From: Panarthropod tiptop/teashirt and spalt orthologs and their potential role as “trunk”-selector genes
A Distribution of zinc fingers (ZF) in the protein coding region of Teashirt, Tiptop, and Tiptop/Teashirt orthologs. The protein is depicted in light grey, “regular” ZFs are in darker grey, and “derived” ZFs are in darkest grey. Note that distribution, number and kind of ZFs are conserved between Drosophila Tiptop and mandibulate Tiptop/Teashirt genes, while the complement of Drosophila Teashirt is clearly derived from this pattern. In the spider, additionally, the first ZF is derived and in the onychophoran, the first ZF is missing. B Sequence comparison of a characteristic region of Spalt and Spalt-related orthologs. Note that they possess a variable number of ZFs, but that they all share a unique combination of ZFs. One N-terminal ZF is linked by seven amino acids (marked in blue) to a downstream second ZF that is linked by a unique number of 11 amino acids (marked in green) to a third ZF. This combination and linking of ZFs is unique for Spalt proteins. Species abbreviations: Dm, Drosophila melanogaster (Insecta: Diptera); Ek, Euperipatoides kanangrensis (Onychophora); Gm, Glomeris marginata (Myriapoda); Pt, Parasteatoda tepidariorum (Chelicerata), and Tc, Tribolium castaneum (Insecta: Coleoptera)