Methyltransferase Like Protein 8 (METTL8)

The deduced proteins have calculated molecular masses of 24, 28.5, and 41 kD, respectively, and all 3 contain a SANT domain at the N terminus. Tip1 contains an alpha-helical LxxLL motif, which is characteristic of nuclear receptor coactivators. Tip2 lacks the LxxLL motif but contains a SAM domain, and Tip3 contains the LxxLL motif, a SAM domain, and a nuclear localization signal. Immunohistochemical analysis detected Tip1 and Tip3 either in nucleus or cytoplasm or concomitantly in both compartments. Tip1 localized to the nucleus upon cell stretch in embryonic mouse lung progenitor cells.Tip1 was absent in undifferentiated embryonic mouse lung mesenchymal cells, but its expression was induced by stretch, whereas Tip3 was expressed in undifferentiated progenitor cells, and its expression was inhibited by stretch.