Analysis of the MurineDtkGene Identifies Conservation of Genomic Structure within a New Receptor Tyrosine Kinase Subfamily

The receptor tyrosine kinaseDtk/Tyro 3/Sky/rse/brt/tifis a member of a new subfamily of receptors that also includesAxl/Ufo/ArkandEyk/Mer.These receptors are characterized by the presence of two immunoglobulin-like loops and two fibronectin type III repeats in their extracellular domains. The structure of the murineDtkgene has been determined. The gene consists of 21 exons that are distributed over 21 kb of genomic DNA. An isoform ofDtkis generated by differential splicing of exons from the 5′ region of the gene. The overall genomic structure ofDtkis virtually identical to that determined for the humanUFOgene. This particular genomic organization is likely to have been duplicated and closely maintained throughout evolution.