GST-Stat1TAD interacts directly with MCM5, but not MCM3.
(A) Schematic view of Stat1α and -β and MCM5 and
MCM3. The domain structure of Stat1 is according to Chen et
al. (7). TAD, transcription activation domain; Y, Tyr-701; S,
Ser-727. (B) MCM5 and MCM3 are among the group of
Stat1TAD-interacting nuclear proteins. Nuclear extracts from U3A cells
were incubated with Sepharose-bead-bound GST or GST-Stat1TAD fusion
proteins. The bound proteins were separated by SDS/PAGE and analyzed
by Western blotting with indicated antibodies. (C)
Stat1TAD interacts directly with MCM5, but not with MCM3.
35S-labeled MCM5 or MCM3 proteins were translated in
vitro and incubated with the indicated GST fusion proteins
bound to Sepharose beads. The bound proteins were separated by
SDS/PAGE and visualized by autoradiography. The bottom panel shows
the various GST fusion proteins separated by SDS/PAGE and visualized
by Coomassie staining.