Functional and expression analyses of mgl-1, a mouse orthologue of lethal giant larvae recessive oncogene.

We recently isolated a few mammalian homologue of Drosophila lethal giant larvae (lgl) recessive oncogene, suggesting that there is functional conservation among proteins of this family. The comparison of amino acid sequence for mgl-1 with other lgl family members using the clustal method showed that they are highly homologous. Therefore, we investigated the biological function of mgl-1, a mouse orthologue of lgl, in the absence of Saccharomyces cerevisiae Sop1 and Sop2, the yeast homologues of the lgl recessive oncogene. Functional analysis showed that the expression of mgl-1 cDNA partially restored salt tolerance in yeast, indicating the evolutionary conservation of lgl family members. Since the developmental expression profile of mgl-1 has not been elucidated, the temporal and spatial expression patterns of mouse mgl-1 during early embryonic development were analyzed. The temporal expression analysis revealed that mgl-1 is expressed throughout embryonic development from days E4.5 to E18.5 with the strong expression at E10.5. The analysis of spatial expression showed that mgl-1 mRNA is detected in CNS, craniofacial region, eyes, limbs, and the gut.