Figure 6

Alterations in pericentric heterochromatin and high molecular weight SUMO-2/3 conjugates in Topors-deficient pMEFs. A. Shown are representative immunofluorescence images of Topors^+/+ and Topors^-/- pMEFs using HP1α and trimethyl-H3K9 antibodies. B. Nuclear lysates from Topors^+/+ and Topors^-/- pMEFs were analyzed by immunoblotting with antibodies recognizing histone H3, trimethyl-H3K9, and HP1α as indicated. C. Analysis of pericentric major satellite repeat transcription in Topors^+/+ and Topors^-/- pMEFs. Purified RNA from Topors^+/+ and Topors^-/- pMEFs was analyzed using semi-quantitative RT-PCR and primers specific for pericentric major satellite repeat transcripts or GAPDH. For major satellite transcripts, results are shown for duplicate assays performed in the presence and absence of reverse transcriptase. The GAPDH assays were performed using a 10-fold dilution of RNA. D. Analysis of ubiquitin, SUMO-1, and SUMO-2/3 conjugates in Topors^+/+ and Topors^-/- pMEFs. Whole cell lysates were analyzed by immunoblotting with the indicated antibodies. Lanes from left to right for Topors^+/+ and Topors^-/- pMEFs indicate serial 2-fold dilutions of cellular lysates.