Fig. 2.

Suv4-20h1 expression in mammalian cells. (A) Suv4-20h1 is a ubiquitous protein. Extracts from indicated cell lines were separated by SDS/PAGE and probed with antibodies to Suv4-20h1. (B) Suv4-20h1 resides in the nucleus. YFP or YFP-Suv4-20h1 were transfected into U2OS-GR cells and images were acquired 18 h later under fluorescent microscope with the FITC filter set. (C) Suv4-20h1 tightly associates with chromatin. U2OS-GR cells were transfected with FLAG-Suv4-20h1 (or “vector” control) and either boiled in 2× SDS sample buffer (total cell lysate) or extracted in a lysis buffer containing 150 or 400 mM NaCl, as indicated, before boiling in 2× SDS. Proteins were separated by SDS/PAGE and probed with anti-FLAG antibodies.