Figure 2.
Interactome profiling of microproteins translated from young sORFs with PRISMA
(A) Schematic of PRISMA including 60 microproteins and four assay controls.
(B) Top: protein evidence per microprotein (Table S2). Bottom: conserved (red) and young (blue) microproteins were sorted based on the highest interaction score (product of fold change and p value).
(C–H) Volcano plots with interactomes of the (C) SOS1 wild-type (WT) control peptide, (D) GLUT1 mutant control peptide, and (E) annotated mitochondrial microprotein MRPL33 (interactors from all tiles are summarized). Additional examples of conserved microproteins are shown in Figure S2M. Volcano plots of summarized interactome results of the three young microproteins (F) RP11-644F5.11-MP, (G) RP11-464C19.3-MP, and (H) SNHG8-MP, the latter being enriched for essential proteins (52 out of 106 interactors; padj = 0.00013; Fisher’s exact test). Additional examples of young microproteins are shown in Figure S2N.
(I) Percentage of essential proteins detected in the interactomes of conserved and young microproteins. No statistical differences were found among both groups (assessed by two-tailed Student’s t test). The horizontal lines indicate 25%, 50%, and 75% quartiles, respectively.
(J) Interaction scores for eleven young microproteins whose top interactor is an essential protein. Asterisks mark microprotein interactomes significantly enriched for essential proteins (assessed by Fisher’s exact test, FDR < 0.05) (Table S3).