Slowly migrating EGF receptor in SDS-PAGE

[Dayanidhi Raman]

Hi, I immunoadsorbed the EGF receptor and eluted it, dialyzed to remove the     detergent in the presence of added lipid, assayed for tyrosine kinase activity. The prep. was run on 7.5% SDS-PAGE after heating the sample at 60C for 3 min.   in Laemmli's sample buffer. The autoradiogram has all receptors at the very top of the gel. Need help desperately!.
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