Fig. 7.

(A) CLSM images showing nuclear localization of DNMT1-RFP in the human glioblastoma U373MG cells not treated (control) and treated with 5 μM 5-azacytidine or 500 nM TSA. In cells treated with 5-azacytidine, inhomogeneous distribution of DNMT1 was observed in the nucleus, reflected by interspersed regions of high- and low-fluorescence intensity. Scale bar, 15 μm. (B) Autocorrelation curves recorded in the nucleus of nontreated cells (control) and in the nucleoplasm (dark spots) in cells treated with 5-azacytidine and TSA. (C) FCS measurements at the intensely fluorescent loci in 5-azacytidine-treated cells are compromised by severe photobleaching, indicating that DNMT1 mobility in these regions is low. (D) Autocorrelation curves shown in panel B normalized to the same amplitude.