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. 2022 Feb 18;11:e71705. doi: 10.7554/eLife.71705

Figure 7. Depletion of translation factors induces Xrp1 expression, eIF2α phosphorylation, reduced translation, and cell competition.

Clones of cells depleted for translation factors are labelled in green. In each case, translation factor depletion reduced translation rate, resulted in competitive cell death at interfaces with wild type cells, induced Xrp1-HA expression, and led to eIF2α phosphorylation. Translation rate, dying cells (activated caspase Dcp1), Xrp1-HA and p-eIF2α are indicated in magenta and in separate channels as labelled. To clarify cell-autonomy, cell death is also shown in higher magnification in Figure 7—figure supplement 2. (A–D) Clones expressing RNAi for eIF4G. (E–H) Clones expressing RNAi for eEF2. (I–L) Clones expressing RNAi for eIF6. In all cases (panels A,E,I), wild-type cells near to cells depleted for translation factors show higher translation rate than other wild type cells. (M) Clones of cells depleted for TAF1B (green) also showed a cell-autonomous reduction in translation rate and non-autonomous increase in nearby wild-type cells (translation rate in magenta, see also M’). (N) Clones of cells depleted for TAF1B (green) showed a non-autonomous increase in RpS6 phosphorylation in nearby cells (magenta, see also N’). Additional data relevant to this Figure is shown in Figure 7—figure supplement 1 and Figure 7—figure supplement 2. Genotypes: A, B, D: {hs:FLP}/+; UAS – RNAieIF4G /+; act> CD2> Gal4, UAS-GFP /+ (line: v17002), C:{hs:FLP}/+; UAS – RNAieIF4G /+; act> CD2> Gal4, UAS-GFP /Xrp1-HA (line: v17002), E, F, H: {hs:FLP}/+; UAS – RNAieEF2 /+; act> CD2> Gal4, UAS-GFP /+ (line: v107268), G: {hs:FLP}/+; UAS – RNAieEF2 /+; act> CD2> Gal4, UAS-GFP / Xrp1-HA (line: v107268), I, J, L:{hs:FLP}/+; UAS – RNAi eIF6 /+; act> CD2> Gal4, UAS-GFP / + (line: v108094), K: {hs:FLP}/+; UAS – RNAieIF6 /+; act> CD2> Gal4, UAS-GFP / Xrp1-HA(line: v108094), M, N: p{hs:FLP}/+; UAS-RNAiTAF1B/+;act> CD2> Gal4, UAS- GFP /+ (line: Bl 61957).

Figure 7.

Figure 7—figure supplement 1. Xrp1 expression, eIF2α phosphorylation, reduced translation, and cell competition after depletion of additional translation factors.

Figure 7—figure supplement 1.

Clones of cells depleted for translation factors are shown in green. In each case, translation factor depletion reduced translation rate, resulted in competitive cell death at interfaces with wild-type cells, induced Xrp1-HA expression, and led to eIF2α phosphorylation. Translation rate, dying cells (activated caspase Dcp1), Xrp1-HA and p-eIF2α are indicated in magenta and in separate channels as labelled. To clarify cell-autonomy, cell death is also shown in higher magnification in Figure 7—figure supplement 2. (A–D) Clones expressing RNAi for eIF5A. (E–H) Clones expressing RNAi for eEF1α. (I,J) Clones expressing RNAi for TAF1B. (I,J) Clones expressing RNAi for TAF1B. Genotypes: A, B, D: {hs:FLP}/+; UAS – RNAieIF5A /+; act> CD2> Gal4, UAS-GFP / + (line: v101513), C: {hs:FLP}/+; UAS – RNAi eIF5A /+; act> CD2> Gal4, UAS-GFP / Xrp1-HA (line: v101513), E, F, H: {hs:FLP}/+; UAS – RNAieEF1α1 /+; act> CD2> Gal4, UAS-GFP /+ (line: v104502), G: {hs:FLP}/+; UAS – RNAieEF1α1 /+; act> CD2> Gal4, UAS-GFP / Xrp1-HA (line: v104502), I: p{hs:FLP}/+; UAS- RNAiTAF1B /+;act> CD2> Gal4, UAS- GFP / Xrp1-HA (line: v105873), J: p{hs:FLP}/+; UAS- RNAiTAF1B /+;act> CD2> Gal4, UAS- GFP /+ (line: Bl 61957).
Figure 7—figure supplement 2. Cell-autonomy of cell death after translation factor depletion.

Figure 7—figure supplement 2.

All panels show cell death, indicated by Dcp1 labeling in magenta in panels A-E and in white in panels A”-E”, associated with clones of cells depleted for the indicated translation factors (green in panels A-E and white in panels A’-E’). The images shown are enlargements of portions of Figure 7B, F and J and Figure 7—figure supplement 1 panels B, F. In all cases, the large majority of the dying cells are cells depleted for translation factors close to the wild-type cells (black in panels A-E and A’-E’), with only a few depleted cells dying away from the clone boundary, and only a few dying wild-type cells. (A-A”) RNAi for eIF4G; (B) RNAi for eEF2; (C) RNAi for eEF1α(D) RNAi for eIF5A; (E) RNAi for eIF6.
Figure 7—figure supplement 3. Translation factor knock-down induces Xrp1 expression.

Figure 7—figure supplement 3.

Knock down of translation factors using nub-Gal4 to drive RNAi in the wing pouch (green) induced Xrp1-HA expression (magenta, and separate channels as indicated). (A) In the control of nub-Gal4 expressing RFP along with w-RNAi, negligible Xrp1-HA was detected (see A’). (B) eIF4G-RNAi. (C) eEF2- RNAi. (D) eEF1α1-RNAi. (E) eIF5A-RNAi. (F) eIF6-RNAi. (G) TAF1B-RNAi (H) TAF1B-RNAi. Genotypes: A: nubGal4, UAS-RFP/+; Xrp1-HA/RNAiw, B: nubGal4, UAS-RFP/ UAS – RNAieIF4G; Xrp1-HA/+, C: nubGal4, UAS-RFP/ UAS –RNAieEF2; Xrp1-HA/+, D: nubGal4, UAS-RFP/ UAS – RNAieEF1α1; Xrp1-HA/+, E: nubGal4, UAS-RFP/ UAS – RNAi eIF5A; Xrp1-HA/+, F: nubGal4, UAS-RFP/ UAS – RNAi eIF6; Xrp1-HA/+, G: nubGal4, UAS-RFP/ RNAiTAF1B; Xrp1-HA/+ (v105873), H: nubGal4, UAS-RFP/ RNAiTAF1B; Xrp1-HA/+ (line: BL 61957).