Western blot using Rreb1 polyclonal antibody (Cat # PAB10322) shows detection ofa predominant band believed to be Rreb1 invarious cell lysates (1 - HEK293, 2 - RFP-Rreb transfected HEK293, 3 - M460 and 4 - T1165). All lysates were loaded at 20 ug per lane and separated by SDS-PAGE. After transfer to nitrocellulose, the membrane was probed with the primary antibody diluted to 1:1,000. The membrane was washed and reacted with IRDye™800 conjugated Gt-a-Rabbit IgG [H&L] MX. IRDye™800 fluorescence image was captured using the Odyssey® Infrared Imaging System developed by LI-COR. IRDye is a trademark of LI-COR, Inc. Size estimation was made by comparison to prestained MW markers as indicated. Personal Communication, Shuling Zhang, CCR, NCI, Bethesda, MD.