Fig. 3.

Repression upon HP1 tethering is modulated by the local chromatin environment. a Positions of the integration sites of TRIP reporters on chromosome 3L. Colors represent chromatin state at the integration site according to the nine-state model (as labeled in Fig. 3b). Centromere position is indicated by black triangle. Plot above the chromosome shows fold downregulation upon Gal4-HP1 tethering. All chromosomes are shown in Additional file 4: Figure S4. b Fold downregulation upon Gal4-HP1 tethering segregated by chromatin state. Median values are indicated by black horizontal bars. Number of reporters integrated in each state is specified above graph. c Quantification of reporter accessibility via tethering of Gal4-Dam in four cell lines each with a single integration. Dam-mediated adenine methylation was assessed by MboI digestion of unmethylated GATC sequences followed by qPCR. Position of qPCR primer pairs is indicated on schematic representation of reporter. Bar graphs show methylation levels measured in two cell lines (labeled A, B) with reporter integration in state 7 heterochromatin (blue) and two cell lines (labeled C, D) with integration in state 3 euchromatin (green). Error bars represent standard deviation of two independent transfections. Measurements were taken with or without reporter induction. d HP1 occupancy levels at reporter integrations sites in state 7 domains as quantified by DamID correlate with downregulation upon Gal4-HP1 recruitment (Pearson). Linear regression (blue) with standard error