Fig. 4: Identification of structural pockets that regulate DDX39 targeting to A-bodies.

a Cartoon of predicted DDX39A structure with residues forming three regulatory pockets highlighted in yellow, red and blue. b Enlarged view of the F184 and S145 (red, surrounding residues pink) and C223 (blue, surrounding residues cyan) hydrophobic pockets. c enlarged view of the T114, I106, N188 and V167 (orange, surrounding residues yellow) hydrophilic pocket. d MCF-7 cells expressing wild-type DDX39A and DDX39B or the indicated DDX39A mutants were subjected to heat shock, visualized, and quantified. Heat shock treated MCF-7 cells expressing constructs containing all possible amino acids at the (e) F184X, (f) C223X, and (g) T114X positions of DDX39A were quantified for A-body targeting efficiency (where X represents amino acids presented along the y-axis of the graph). Background colors indicate amino acid hydrophobicity (orange), polarity (blue), negative charge (purple), or positive charge (green). For each quantification (d−g), 10 cells were analyzed per replicate, and values represent means ± s.e.m. (n  =  3 independent experiments, a two-tailed Student’s t test was used: *p ≤ 0.05). Not significant (ns). Source data for all graphs are provided with this paper.