dimer????

 hii....
my protein is a transcriptional regulator and has the domains that can dimerize it.....i mean there is dimer formation .....when i purified the recombinant protein i was not able to see any dimers on SDS -PAGE....there was no Beta mercaptoethanol or any other reducing agent in the loading buffer......but yes i purify my protein from the cytosolic fraction and so i added beta mercaptoethanol in the sonication buffer.....could this be a reason for not detecting dimers in the sds page gel?????

 HI Monisha

It could be that your protein is a homodimer so you are unable to make it in SDS PAGE.

hi argerine


 yup i expect my protein to be a homodimer but in that case i shud observe 2 bands on sds ....one corresponding 2 monomer and other for the dimer just on double the molecular weight.

 Hi Monisha 

Add a reducing agent in your sample buffer and proceed with expt. You can also add urea upto 6M for better results as well.

FYI : Urea SDS PAGE  gels are dense and U may get narrowing effect so preferably use urea in sample buffer.