Table 1.
Mapping interactions between calnexin, calreticulin, ERp57, and PDI using MYTHS
CNX H21P482 | ERp57 A24-L505 | PDI D18-L508 | ERp57 K362R | ERp57 F386S | ERp57 W405R | ERp57 F476S | pLJ96 | GST | |
---|---|---|---|---|---|---|---|---|---|
ERp57 A24-L505 | +++ | − | + | − | − | − | − | − | +++ |
CNX H21−P482 | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CNX P270−F415 (11112222) | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CNX D289−N393 (111222) | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CNX P310−P378 (1122) | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CRT E18-L417 | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CRT D201-A307 (111222) | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
CRT A223-P283 (1122) | − | +++ | − | +++ | +++ | +++ | +++ | − | +++ |
PDI D18-L508 | − | + | − | n/a | n/a | n/a | n/a | − | +++ |
CNX2pmA | − | + | − | +++ | +++ | +++ | +++ | − | +++ |
CNX6pmA | − | − | − | − | − | − | − | − | +++ |
pLJ89 | − | − | − | − | − | − | − | − | +++ |
GST |
+++ |
+++ |
+++ |
+++ |
+++ |
+++ |
+++ |
+++ |
+++ |
Results of using several calnexin and calreticulin P-domain constructs to map their interactions with ERp57. CNX and CRT deletion mutants are indicated, with the number of P-domain repeat motifs indicated in parenthesis. Specific point mutations in calnexin confirm acidic residues necessary for interaction. Error-prone PCR identifies point mutations in ERp57 that complement the mutated calnexin P-domain. The nature of each mutant fusion protein is described in the text. Plus symbols indicate the presence and strength of an interaction (‘+++' strongest to ‘+' weakest), and ‘−' indicates no interaction detected. ‘n/a' indicates data not available. |