Fig. 1. Sequence of the Tribolium Giant ortholog. (A) Alignment of Tribolium and Drosophila Giant using Clustal W. Identical and similar amino acids are highlighted in black and grey, respectively. Longer sequence stretches without homology were omitted from the Dm'Giant sequence (indicated by dots, the number of omitted amino acids is indicated). The DNA-binding leucine zipper (large box) is 63% identical and 78% similar between both insects. The binding domain of the co-repressor CtBP (small box) is highly conserved, as are a number of additional motifs of unknown function. These conserved motifs upstream of the leucine zipper substantiate the orthology of Tc'Giant and Dm'Giant, as they are not present in other leucine zipper genes. Note that Dm'Giant is twice as large as the predicted beetle protein. (B) Alignment of the leucine zippers of Tc'Giant, Dm'Giant, Dm'CG4575 and Hs'HLF, the Human hepatic leukemia factor. Dashes indicate sequence identity. The position of the three nested PCR primers used for isolation of Tc'giant is given below.