Figure 1.

The GRASP55 antibody recognizes a single-polypeptide in NRK cell extracts. (A) Affinity-purified antiserum and preimmune serum were tested by Western blotting of either purified recombinant protein (lane 1) or total NRK lysate (lane 2). (B) Preimmune or affinity-purified anti-GRASP55 antibodies were tested by immunofluorescence microscopy of NRK cells. The anti-GRASP55 antibody recognizes the Golgi apparatus as revealed by colocalization with bona fide Golgi proteins. (C) HeLa cells were stained with antibodies for Golgi markers (green) GM130 and p230 or transfected with ManII-GFP (cis/medial-Golgi marker). Colocalization with GRASP55 (red) was assessed using confocal laser scanning microscopy. Each picture is the Z-projection of a stack made up of six planes.