Fig. 4.

Mutations in Prdx6 30–40 aa region affect protein targeting to lysosome-related compartments in MLE-12 cells. A: sequence of the Prdx6 30–40 aa NH₂-terminal region. One 5-aa sequence at top indicates the lipase motif (18, 31), and two 5-aa sequences at bottom indicate potential glycine “zippers” (29). B: schematic representation of point mutations in GFP:Prdx6 constructs used in these studies. C: effect of point mutations on colocalization of full-length GFP:Prdx6 and a GFP:Prdx6 peptide (31–40 aa) with Nile Red in MLE-12 cells. Point mutations S32A and G30L/G34L were studied in the full-length protein and S32A and S38L were studied in the peptide. Left panels: fusion construct expressed in the transfected cells. Middle panels: lysosome-related organelles stained with Nile Red. Right panels: colocalization, detected by yellow color, in the merged image. D: same as C, but with H26A mutation in the full-length GFP:Prdx6 construct. LAMP-1 was used as the lysosome-related organelle marker.