HI ALL, I am working on H.pylori mediated gastritis and looking for nfkb11 expression.

I am getting upregulation of p50, I like to know possibility of homo and heterodimer formation when infecting with H.pylori. I need to show formation of p50:p50 but 

is their formation of only 100kda after dimerization or p105 which is precursor of p50 can also dimerise with individual with p50 to form 165kda?

I have planned to differentiate formation of heterodimer with IP, i have made two p50 construct, one with flag tag ans another with his tag, but i need to know if i am going to contransfect these contruct in raw and then i will see homodiemr formation, can anyone claim that since we already raise the level of p50 by transfcting in the macropahge cell line so its not a real observation, because the best i Know being NFKB- so dynamic system, its all depend on affinity and maount of individual subunits

Somebody working on nfkb please suggest some technique to study homodimer formation?