Cytolethal Distending Toxins Require Components of the ER-Associated Degradation Pathway for Host Cell Entry
Figure 5
Identification of Derl2 domains required for CDT intoxication.
(a–c) CHO-CDTRC1 cells expressing empty vector (squares), Derl1-S (triangles), or Derl2-S (diamonds) were intoxicated in each panel, similar to Fig. 1, and compared to derlin variants indicated below. Anti-DERL1 (a) or anti-Derl2 (b, c) western blot of S-protein agarose precipitated protein from normalized cell lysates show expression levels of chimeric derlins. Cartoons depict Derl1 (black) and Derl2 (grey) sequences in each chimera. (a) CHO-CDTRC1 cells expressing Derl1-S (triangles, #1) or Derl21–187:Derl1189–251-S tag (circles, #2) were challenged with Hd-CDT. (b) CHO-CDTRC1 cells expressing Derl2-S (diamonds, #1), Derl21–112:Derl1114–121:Derl2120–239-S (circles, #2) or Derl21–161:Derl1163–171: Derl2171–239-S (inverted triangles, #3) were intoxicated as above. (c) CHO-CDTRC1 cells expressing Derl2-S (diamonds, #1), Derl11–88:Derl288–239-S (open boxes, 2), Derl11–138:Derl2138–239-S (open triangles, #3) or Derl11–162:Derl2162–239-S (open diamonds, #4) were intoxicated as above. Data are representative of at least three independent experiments performed in triplicate, percent viability is normalized to unintoxicated controls and error bars indicate standard error.