FIG. 2.

U122 is expressed in SARS CoV-infected Vero E6 cells. (A) Analysis of the U122 putative sequence predicts a signal peptide sequence (underlined) at the N terminus, the cleavage site of which is indicated with an arrow. A putative membrane-spanning domain (boxed) and an ER retrieval motif (bold italics) are found at the C terminus. (B) Blots of Vero E6 cells probed with mouse anti-U122 antiserum. Lane 1, 20 μg of protein from uninfected cells; lanes 2 and 3, 20-μg samples of proteins from SARS-CoV-infected cells harvested at about 25% CPE and 50 to 75% CPE, respectively; lane 4, 15 μg of total protein from cells transfected with pXJU122 plasmid; lane 5, 20 μg of total lysate from an IBV-infected cell culture. (C) Uninfected and virus-infected cells at 25% CPE were fixed and stained with mouse anti-U122 antibody. WB, Western blot; mαU122, mouse anti-U122 antibody.