(A–C) Representative electron micrographs (A), IRF3 stimulatory activity (B), and ATPase activity (C) of G495R in complex with the sense (+) or antisense (−) strand of Alu from the NICN1 3’UTR.
(D) Schematic of the RNase H-based method to selectively cleave unpaired, but not paired Alu RNAs.
(E) Gel analysis of the RNase H assay. In vitro transcribed Alu RNAs (from NICN1 3’UTR) were subjected to the RNase H assay as described in (D). An oligo targeting GAPDH (αGAPDH) was used for negative controls.
(F) Quantitation of Alu:Alu hybrids in cytosolic RNA. The RNase H assay in (D) was performed using purified cytosolic RNA from 293T cells, and remaining Alu(+) and Alu(−) were quantitated relative to the spike-in control.
(G) The levels of Alu(+), Alu(−), GAPDH and ACTB (right) relative to the spike-in control before and after the RNase A protection assay. CytoRNA-0.0, −0.5 and −2.0 indicate RNAs recovered after digestion with 0.0, 0.5 and 2.0 ng/µl RNase A in the presence or absence of G495R.
Data represent mean ± SD (n=3) for (C), (F) and (G). See also Figure S5.