Fig 4. Simultaneous detection of co-transfected sequences in COLO 320DM cells.

A mixture of pKV-AR1 DNA and G5 inverted (A and B) or direct (C and D) repeat DNA was co-transfected into COLO 320DM cells, and the stable transformants were selected by blasticidin for a month. Metaphase chromosome spreads (A to C) or chromatin fibers (D) were prepared from these cells. The slides were simultaneously hybridized with biotin-labeled G5 probe and DIG-labeled pKV-AR1 plasmid probe, and the hybridized probes were detected by red (Alexa594) or green (FITC) fluorescence, respectively. DNA was counterstained blue with DAPI in panels A to C. Among metaphase chromosomes, strong G5 signals and weak pKV-AR1 signals were co-localized at multiple DMs (A) or HSRs (B and C). In panel D, small pKV-AR1 signals (green arrowheads) were periodically embedded in the long stretch of G5 signals (red broken lines).