UPF2 transiently interacts with translation factors.

<p><b>(A)</b> Western blots of anti-HA co-immunoprecipitation experiment from 293T cells overexpressing H16-UPF2^R. Protein hyperphosphorylation, dephosphorylation and RNase A treatment conditions were as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0150239#pone.0150239.g007" target="_blank">Fig 7</a>. <b>(B)</b> Western blot of co-immunoprecipitation of endogenous EIF4A2 from 293T cells with an antibody against the n-terminus of EIF4A2 (lanes 3,4, 6,7) either with (lanes 4 and 7) or without RNase A treatment (lanes 3 and 6). Whole IgG was used as a control (lanes 2 and 5). Input, unbound (5x10⁵ cell equivalents each) and immunoprecipitated material (equivalent to 1x10⁷ cells) was used in (A) and (B). White and black triangles denote the position of the overexpressed and endogenous proteins, respectively. <b>(C-E)</b> Proximity ligation assays (PLA) probing for the effect translation inhibition on the pairwise co-localization of UPF2 and EIF4A2 (C), UPF2 and ribosomal protein RPS2 (D), and UPF2 and SMG1 (E). HeLa Tet-Off TCRβ ter68 cells (clone 2.2) were grown and where indicated treated with puromycin (Puro), cycloheximide (CHX) or arsentite. The antibody pairs for detection are depicted above the images. Omission of one or both primary antibodies controlled for the specificity of the PLA signal.