Figure 6. Genetic interactions between Ras signalling and chromatin remodelling.
(A) Edges show the detected genetic interactions in the interaction screen of members of the SWI/SNF complex with RasGAP1 and members of the Ras pathway. An edge is drawn if a significant interaction (FDR 0.01) was detected for at least one phenotype. Edges with attributed epistatic interactions are shown in blue (alleviating epistasis) and red (aggravating epistasis). Black edges indicate gene pairs for which a genetic interaction was detected, but directionality could not be assigned. (B) Scheme of the Ras/MAP kinase pathway. RasGAP1 inhibits the activity of the pathway by catalysing the intrinsic GTPase activity of Ras. (C) Exemplary the cell number, area of nuclei and eccentricity phenotypes are shown that guide the directionality estimate. Blue arrows indicate the RasGap1 phenotype, the SWI/SNF phenotype is depicted by orange arrows and the black arrows show the genetic interaction between SWI/SNF and RasGap1. (D) In vivo validation of genetic interaction of SWI/SNF and constitutively active Ras85D. From left to right: Normal eye in wild type flies (Oregon-R, +/+). Rough eye phenotype upon expression of Ras85DV12 under the sevenless promotor (sev-Ras85DV12/+). Strong rescue after heterozygous removal of the SWI/SNF complex members osa (sev-Ras85DV12/osa2), Snr1 (sev-Ras85DV12/Snr101319) and brm (sev-Ras85DV12/brm2). (E) Quantification of the rescue of the rough eye phenotype. Black colour: expression of Ras85DV12 in the eye of otherwise wild-type flies results in a rough eye phenotype. Grey to white colour scale shows the strength of the rescue of the rough eye phenotype in flies expressing Ras85DV12 in the eye and with heterozygous mutants of SWI/SNF complex members osa (sev-Ras85DV12/osa2), Snr1 (sev-Ras85DV12/Snr101319) and brm (sev-Ras85DV12/brm2). (F) Cell viability of isogenic HCT116 cells 96 hr after siRNA against members of the SWI/SNF complex (SMARCA4, SMARCB1, and ARID1A). Right: parental HCT116 KRAS mutant cells (KRASG13D/+); left: isogenic cell line HCT116 KRAS wt (KRASKO/+). The experiment was performed in four biological replicates.
Figure 6—figure supplement 1. Ras-induced cell growth requires SWI/SNF complex function.
