Slowly migrating EGF receptor

[Nora Plesofsky-Vig]

Our experience with a different membrane protein may (or may not) be  
relevant. The subunit I of mitochondrial cytochrome c oxidase is a  
very hydrophobic protein that aggregates under the typical conditions  
of preparation for SDS gel electrophoresis (as you describe). What we  
do to minimize/prevent aggregation is to solubilize the oxidase  
enzyme in Laemmli sample buffer for 1 hour at room temperature and  
then leave it at 4oC overnight, prior to loading and running the gel.  
High temperature treatment appears to be the problem.

Good luck.

Nora Plesofsky-Vig
nora at biosci.cbs.umn.edu