Fig. 1. The Ptp52F gene. (A) Map of the deficiencies used for the EMS lethal screen. The position of the Ptp52F gene is indicated by the shaded bar. (B) Exon maps of Ptp52F and the adjacent DLis1 genes; distal (toward the telomere) is towards the left, so the orientation is flipped relative to A. (C) Sequence of the DPTP52F preprotein. Indicated sequences are: putative signal sequence, thin underline; FN3 repeats, thick underlines; putative transmembrane domain, double underline; PTP domain, broken underline; bold, highly conserved PTP domain residues; letters in shaded bars, amino acid changes produced by mutations. (D) Lineup of the DPTP52F FN3 repeats with two FN3 repeats from DPTP10D and the seventh FN3 repeat in human fibronectin. Shaded bars, conserved residues. Consensus residues indicated in bold.