Extended Data Fig. 4: OspC3 modification of caspase-4/11 contains a step of ADP-ribosylation.
From: Shigella evades pyroptosis by arginine ADP-riboxanation of caspase-11
a, HPLC–MS quantification of small-molecule products present in indicated in vitro caspase-4 modification reactions. Mean values ± s.d., n = 3 (independent experiments), two-tailed unpaired Student’s t-test (***P < 0.001, **P < 0.01, ns, non-significant). b, c, Assessing the ability of various NAD+ analogues or derivatives to support in vitro modification of caspase-4-p30-C/A by OspC3. b, The reactions were subjected to native/SDS-PAGE analyses. Control, OspC3-modified caspase-4-p30-C/A in bacteria. c, Following the modification, caspase-4-p30 was digested with chymotrypsin and analysed by mass spectrometry. Shown are the extracted ion chromatograms of the R314-containing peptides. Mass changes of each analogue from NAD+ are illustrated underneath the corresponding chromatograms. A, adenine; N, nicotinamide; P, phosphate; R, ribose. d, e, Caspase-4/11-p30-C/A modified by OspC3 in bacteria was treated with SdeA or NUDT16 overnight. d, The caspase-4 samples were then immunoblotted with an anti-ADP-ribosylation antibody. e, Caspase-4/11 after NUDT16 treatment was digested with chymotrypsin and analysed by mass spectrometry. Shown are extracted ion chromatograms of the R314/R310-containing peptides. All data are representative of three independent experiments. For gel source data, see Supplementary Fig. 1.
