Characterization of TFG in Mus musculus and Caenorhabditis elegans

TFG was discovered as a fusion partner of NTRK1 in human papillary thyroid carcinoma. We assembled the mouse TFG cDNA from EST sequences and 5' end RA CE product, identified full coding length TFG EST clones in pig (c17b07) an d Schistosoma mansoni (SMNAS62), and analyzed the genomic structure of TFG in Caenorhabditis elegans (Y63D3A). The protein sequences of mouse, pig, an d S. mansoni TFG are highly homologous to human TFG. The C. elegans sequenc e has diverged, but its predicted secondary structure is remarkably conserv ed. Human, mouse, and C. elegans TFG contain a putative trimeric N-terminal coiled-coil domain, glycosylation, myristylation, and phosphorylation site s, and SH2- and SH3-binding motifs. The SH2-binding motif is absent in C. e legans TFG. The expression of TFG does not vary among 7, 11, 15, and 19 day mouse embryonal stages. Pn situ hybridization with a TFG probe in 10, 5-da y whole mouse embryos showed preferential staining of the limb buds, branch ial arches, nasal processes, and brain, and weak staining of the primitive spinal cord and dorsal root ganglia. (C) 1999 Academic Press.