Co-IP problems with band sizes - Different band sizes in input and pulled down (May/30/2009 )
Hey
I would like to get some opinions on my problem. I have performed standard co-immunoprecipitation with the antibody against protein A. I want to confirm previously published protein protein interactions. Between the above mentioned protein A and "my protein B'. However the input sample with antibody anti-B on WB gives band size 90 kda which is correct, but using the same antibody after Co-IP I see the band about 75-80 kDa. Is it possible that in complexes the protein got smaller? or is it more likely unspecific band. Thank you for time and efforts.
-malena.a-
Photo?
Also, the salt concentration and detergents in your samples can affect running mobility.
Try to ensure that buffers in input and IP are consistent.
-mikew-