Phylogeny-guided mutational analysis of Luc7. The primary structures of the Luc7 polypeptides of Saccharomyces cerevisiae (Sce), Aspergillus fumigatus (Afu), Trichoderma atroviride (Tat), and Homo sapiens (Hsa) are aligned. Positions of side chain identity/similarity are indicated by (•). Gaps in the alignment are denoted by dashes. Forward and reverse arrows indicate the boundaries of S. cerevisiae Luc7 N-terminal and C-terminal truncations, respectively. Black arrows denote biologically active truncations; red arrows indicate lethal truncations. The conserved amino acids of the N-terminal CCCH ZnF1 module are shaded gold; the amino acids of the conserved C-terminal CCHH ZnF2 module are shaded green. Eight other conserved positions subjected to mutagenesis in the present study are shaded magenta.
