FIG. 4.

E48G substitution in Qk1 abolishes homodimerization but not RNA binding. (A) HeLa cells were transfected with HA- or myc-tagged Qk1 and/or Qk1:E➛G as indicated. The total cell lysate (TCL) as well as anti-myc (myc) and IgG (C) immunoprecipitates were immunoblotted with anti-HA antibody. The bands representing HA-Qk1 or HA-Qk1:E➛G are indicated on the left. The migration of the heavy chain of IgG is also indicated. (B) Total cell lysates corresponding to those of panel A were immunoblotted with anti-myc antibodies. (C) Immunoprecipitated Qk1 or Qk1:E➛G was incubated with labeled RNA as described in Materials and Methods.