Phenotypic differences in PrPC densities at the ECM upon Papss2 and Fn1 loss of function AGene expression of Papss2 and Fn1 was silenced in R7 cells prior to immunolabelling with ICSM18. Phenotypic differences in PrPC densities at the ECM upon Papss2 and Fn1 loss of function AGene expression of Papss2 and Fn1 was silenced in R7 cells prior to immunolabelling with ICSM18. In addition, Prnp was overexpressed using pLNCX2 vector. Representative images of serial confocal z‐stacks, acquired at identical laser setting, are shown. BMean fluorescence intensities of Papss2‐ and Fn1‐silenced cells labelled with ICSM18 and anti‐mouse Alexa Fluor 488 antibodies were acquired according to the procedure described in Supplementary Fig S7. Mean fluorescence intensities of at least 40 intensity profiles ± standard error of the means, as well as upper and lower limits of 95% confidence intervals are shown. C, DPrPC protein expression levels in R7 cells at 3 days after transfection with siRNA against Papss2, Fn1, Itga8, and scrambled RNA control are shown (C) and quantified for three biological repeats with β‐actin as an endogenous control (D; anti‐actin, clone ACTN05 (C4), Abcam). Significant changes (P < 0.05) between gene silencing of candidates and scrambled RNA control are shown (*). Masue M Marbiah et al. EMBO J. 2014;33:1527-1547 © as stated in the article, figure or figure legend