Dynabeads His Tag
I performed a co-IP with a His tag protein and a flag tag protein using the dynabeads His-Tag. From doing co-Ip experiments using both flag and HA antibodies I have established these two proteins associate. When I performed this experiment using the dynabeads His-Tag ( I wanted to use this method because I want to use the alliance for a native gel) I found when through immunoblot analysis probing with the Flag antibody the negative control sample which is just transfected with the Flag construct, had identical levels of Flag as the samples that were co-transfected with both the HIS and Flag tag constructs, thus the beads are binding to nonspecific proteins. Can anyone give me some feedback to alleviate this problem.