WB Loading control for large protein - (May/11/2006 )

Hi Everyone,
I am looking at a mouse protein that is 450 KD in size. I want a some sort of loading control that I can see on the same blot as my protein (it needs to be larger than 100KD). I thought about using myosin, however all the antibodies I found were for smooth muscle only. I am working in mouse fibroblasts and will need something that is expressed in these cells. Any suggestions?

How about Zona-Occludens 1
225 kDa