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Cell Competition Modifies Adult Stem Cell and Tissue Population Dynamics in a JAK-STAT-Dependent Manner.

Kolahgar G, Suijkerbuijk SJ, Kucinski I, Poirier EZ, Mansour S, Simons BD, Piddini E - Dev. Cell (2015)

Bottom Line: Throughout their lifetime, cells may suffer insults that reduce their fitness and disrupt their function, and it is unclear how these potentially harmful cells are managed in adult tissues.We address this question using the adult Drosophila posterior midgut as a model of homeostatic tissue and ribosomal Minute mutations to reduce fitness in groups of cells.Finally, we show that winner cell proliferation is fueled by the JAK-STAT ligand Unpaired-3, produced by Minute(-/+) cells in response to chronic JNK stress signaling.

View Article: PubMed Central - PubMed

Affiliation: The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.

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Wild-Type Cells Induce Accelerated Turnover of M−/+ Intestinal Cells(A and A′) Posterior midgut cross-sections along the xy, xz, and yz axes showing the epithelial walls and intestinal lumen. M−/+ clones (2×GFP, arrows) were generated in a pseudo-WT background by hs-Flp recombination (WT; 1×GFP, asterisks) (genotype: Df(1)R194, w/hsflp; FRT40, ubiGFP/P[RpL36+w+], FRT40). Delaminated cells seen in the lumen were assigned to the WT or M−/+ population based on GFP intensity, shown in grayscale (A′).(B) Cartoon depicting epithelial cells delaminating from the epithelium into the gut lumen. PM, peritrophic matrix.(C) Box plots displaying the percentage of delaminating cells throughout the 3D volume of the gut lumen for WT or M−/+ cells in guts as in (A) (n = 21 guts; p: Mann-Whitney test).(D–D″) M−/+ posterior midgut harboring hs-Flp-induced WT clones (GFP-negative) stained with the cell-death label Sytox (red in D and D′ [arrows]; gray in D″) (hsflp/+; FRT82B, ubiGFP, RpS3/FRT82B).(E) Box plots displaying the percentage of M−/+ Sytox+ cells among the cells near (less than two rows of cells) or far (more than two rows of cells) from WT clones (n = 11 guts; genotype as in D) or the percentage of Sytox+ cells in control WT cells near or far from WT clones (n = 12 guts; genotype: hsflp/+; +/CyO; FRT82B, ubiGFP/FRT82B) (p = 0.03 for WT/M−/+ and p = 0.52 for WT/WT, Mann-Whitney test).(F–F″) Cleaved PARP detection (green; arrows) reveals frequent apoptosis in M−/+ cells bordering WT cells (β-Gal-negative) (hsflp/+; FRT40, M(2), arm-lacZ/FRT40; actGal4, UAS mCD8 Parp Venus/+).(G and H) M−/+ posterior midgut harboring hs-Flp-induced WT clones (G and G′). Clones were left to grow for 4 days ACI and then TCFDN was expressed continually for 5–6 days across progenitor cells (PSwitchamp>TCFDN, +RU486) to induce ISC differentiation (hsflp/+; PSwitchAMP/UAS TCFDN; FRT82B, ubiGFP, RpS3/FRT82B). Clones were scored for the presence or absence of ISCs (scoring small DAPI+ cells as a proxy for ISCs) and further analyzed for the presence of Sytox+M−/+ cells at clone boundaries (arrows in G and G′) (n = 52 ISC− clones; n = 48 ISC+ clones). Differences in the distribution of clones between these two categories were not significantly different (p = 0.24, Fisher’s exact test) (H).Scale bars represent 50 μm. Genotypes are indicated in parentheses throughout the figure legends. Clones (defined in the z volume) are marked with dotted lines throughout the figures. See also Figure S1.
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fig1: Wild-Type Cells Induce Accelerated Turnover of M−/+ Intestinal Cells(A and A′) Posterior midgut cross-sections along the xy, xz, and yz axes showing the epithelial walls and intestinal lumen. M−/+ clones (2×GFP, arrows) were generated in a pseudo-WT background by hs-Flp recombination (WT; 1×GFP, asterisks) (genotype: Df(1)R194, w/hsflp; FRT40, ubiGFP/P[RpL36+w+], FRT40). Delaminated cells seen in the lumen were assigned to the WT or M−/+ population based on GFP intensity, shown in grayscale (A′).(B) Cartoon depicting epithelial cells delaminating from the epithelium into the gut lumen. PM, peritrophic matrix.(C) Box plots displaying the percentage of delaminating cells throughout the 3D volume of the gut lumen for WT or M−/+ cells in guts as in (A) (n = 21 guts; p: Mann-Whitney test).(D–D″) M−/+ posterior midgut harboring hs-Flp-induced WT clones (GFP-negative) stained with the cell-death label Sytox (red in D and D′ [arrows]; gray in D″) (hsflp/+; FRT82B, ubiGFP, RpS3/FRT82B).(E) Box plots displaying the percentage of M−/+ Sytox+ cells among the cells near (less than two rows of cells) or far (more than two rows of cells) from WT clones (n = 11 guts; genotype as in D) or the percentage of Sytox+ cells in control WT cells near or far from WT clones (n = 12 guts; genotype: hsflp/+; +/CyO; FRT82B, ubiGFP/FRT82B) (p = 0.03 for WT/M−/+ and p = 0.52 for WT/WT, Mann-Whitney test).(F–F″) Cleaved PARP detection (green; arrows) reveals frequent apoptosis in M−/+ cells bordering WT cells (β-Gal-negative) (hsflp/+; FRT40, M(2), arm-lacZ/FRT40; actGal4, UAS mCD8 Parp Venus/+).(G and H) M−/+ posterior midgut harboring hs-Flp-induced WT clones (G and G′). Clones were left to grow for 4 days ACI and then TCFDN was expressed continually for 5–6 days across progenitor cells (PSwitchamp>TCFDN, +RU486) to induce ISC differentiation (hsflp/+; PSwitchAMP/UAS TCFDN; FRT82B, ubiGFP, RpS3/FRT82B). Clones were scored for the presence or absence of ISCs (scoring small DAPI+ cells as a proxy for ISCs) and further analyzed for the presence of Sytox+M−/+ cells at clone boundaries (arrows in G and G′) (n = 52 ISC− clones; n = 48 ISC+ clones). Differences in the distribution of clones between these two categories were not significantly different (p = 0.24, Fisher’s exact test) (H).Scale bars represent 50 μm. Genotypes are indicated in parentheses throughout the figure legends. Clones (defined in the z volume) are marked with dotted lines throughout the figures. See also Figure S1.

Mentions: Induction of death in weaker cells is a major hallmark of cell competition. To look for evidence of cell competition in the posterior midgut, we therefore asked whether wild-type intestinal cells induce accelerated turnover of neighboring M−/+ cells. Depending on the experiment, here and throughout this study, we induced either the formation of wild-type (M+/+) clones in a M−/+ gut or, vice versa, we generated M−/+ clones in a (pseudo) wild-type gut. Clones were induced in recently eclosed adults by heat shock-induced, Flp-mediated mitotic recombination. In the posterior midgut, cells that are turned over are shed into the intestinal lumen following epithelial delamination. Consistent with our hypothesis, we found that in mosaic guts containing wild-type and M−/+ cells, delaminated cells (normalized to the abundance of each cell population) were more likely to be M−/+ than wild-type (Figures 1A–1C). This indicated that in competing guts, M−/+ cells have an accelerated turnover compared to wild-type cells. However, although their relatively shorter lifetime could be a consequence of their interaction with wild-type cells, it could also result from the M−/+ mutation per se. To test the latter possibility, we compared relative turnover rates of wholly wild-type and wholly M−/+ posterior midguts using a previously published genetic tool that allows pulse labeling all cells in a gut and then chasing to monitor how long they persist (Jiang et al., 2009). This revealed that, in fact, cell turnover in M−/+ guts is slower than in wild-type guts (Figures S1A–S1D). This rules out the possibility that the accelerated turnover observed in competing guts is an intrinsic property of M−/+ cells and suggests that it is induced by cell competition. Next, we compared directly the relative cell-death frequency of M−/+ cells close to wild-type cells and of M−/+ cells far away (i.e., greater than two cell diameters away; see Experimental Procedures) from wild-type cells within the same guts using the cell-death marker Sytox (Figures 1D and 1E; Figures S1E–S1F″). Importantly, the cell-death frequency of M−/+ cells was specifically increased in the proximity of wild-type cells (Figures 1D and 1E), indicating that this was a result of cell-cell interaction. This finding was further confirmed by analysis of PARP cleavage (Figures 1F–1F″), a readout of caspase activation (Williams et al., 2006) (Figures S1E–S1F″), which also indicates that (at least some) cells die of apoptosis.


Cell Competition Modifies Adult Stem Cell and Tissue Population Dynamics in a JAK-STAT-Dependent Manner.

Kolahgar G, Suijkerbuijk SJ, Kucinski I, Poirier EZ, Mansour S, Simons BD, Piddini E - Dev. Cell (2015)

Wild-Type Cells Induce Accelerated Turnover of M−/+ Intestinal Cells(A and A′) Posterior midgut cross-sections along the xy, xz, and yz axes showing the epithelial walls and intestinal lumen. M−/+ clones (2×GFP, arrows) were generated in a pseudo-WT background by hs-Flp recombination (WT; 1×GFP, asterisks) (genotype: Df(1)R194, w/hsflp; FRT40, ubiGFP/P[RpL36+w+], FRT40). Delaminated cells seen in the lumen were assigned to the WT or M−/+ population based on GFP intensity, shown in grayscale (A′).(B) Cartoon depicting epithelial cells delaminating from the epithelium into the gut lumen. PM, peritrophic matrix.(C) Box plots displaying the percentage of delaminating cells throughout the 3D volume of the gut lumen for WT or M−/+ cells in guts as in (A) (n = 21 guts; p: Mann-Whitney test).(D–D″) M−/+ posterior midgut harboring hs-Flp-induced WT clones (GFP-negative) stained with the cell-death label Sytox (red in D and D′ [arrows]; gray in D″) (hsflp/+; FRT82B, ubiGFP, RpS3/FRT82B).(E) Box plots displaying the percentage of M−/+ Sytox+ cells among the cells near (less than two rows of cells) or far (more than two rows of cells) from WT clones (n = 11 guts; genotype as in D) or the percentage of Sytox+ cells in control WT cells near or far from WT clones (n = 12 guts; genotype: hsflp/+; +/CyO; FRT82B, ubiGFP/FRT82B) (p = 0.03 for WT/M−/+ and p = 0.52 for WT/WT, Mann-Whitney test).(F–F″) Cleaved PARP detection (green; arrows) reveals frequent apoptosis in M−/+ cells bordering WT cells (β-Gal-negative) (hsflp/+; FRT40, M(2), arm-lacZ/FRT40; actGal4, UAS mCD8 Parp Venus/+).(G and H) M−/+ posterior midgut harboring hs-Flp-induced WT clones (G and G′). Clones were left to grow for 4 days ACI and then TCFDN was expressed continually for 5–6 days across progenitor cells (PSwitchamp>TCFDN, +RU486) to induce ISC differentiation (hsflp/+; PSwitchAMP/UAS TCFDN; FRT82B, ubiGFP, RpS3/FRT82B). Clones were scored for the presence or absence of ISCs (scoring small DAPI+ cells as a proxy for ISCs) and further analyzed for the presence of Sytox+M−/+ cells at clone boundaries (arrows in G and G′) (n = 52 ISC− clones; n = 48 ISC+ clones). Differences in the distribution of clones between these two categories were not significantly different (p = 0.24, Fisher’s exact test) (H).Scale bars represent 50 μm. Genotypes are indicated in parentheses throughout the figure legends. Clones (defined in the z volume) are marked with dotted lines throughout the figures. See also Figure S1.
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fig1: Wild-Type Cells Induce Accelerated Turnover of M−/+ Intestinal Cells(A and A′) Posterior midgut cross-sections along the xy, xz, and yz axes showing the epithelial walls and intestinal lumen. M−/+ clones (2×GFP, arrows) were generated in a pseudo-WT background by hs-Flp recombination (WT; 1×GFP, asterisks) (genotype: Df(1)R194, w/hsflp; FRT40, ubiGFP/P[RpL36+w+], FRT40). Delaminated cells seen in the lumen were assigned to the WT or M−/+ population based on GFP intensity, shown in grayscale (A′).(B) Cartoon depicting epithelial cells delaminating from the epithelium into the gut lumen. PM, peritrophic matrix.(C) Box plots displaying the percentage of delaminating cells throughout the 3D volume of the gut lumen for WT or M−/+ cells in guts as in (A) (n = 21 guts; p: Mann-Whitney test).(D–D″) M−/+ posterior midgut harboring hs-Flp-induced WT clones (GFP-negative) stained with the cell-death label Sytox (red in D and D′ [arrows]; gray in D″) (hsflp/+; FRT82B, ubiGFP, RpS3/FRT82B).(E) Box plots displaying the percentage of M−/+ Sytox+ cells among the cells near (less than two rows of cells) or far (more than two rows of cells) from WT clones (n = 11 guts; genotype as in D) or the percentage of Sytox+ cells in control WT cells near or far from WT clones (n = 12 guts; genotype: hsflp/+; +/CyO; FRT82B, ubiGFP/FRT82B) (p = 0.03 for WT/M−/+ and p = 0.52 for WT/WT, Mann-Whitney test).(F–F″) Cleaved PARP detection (green; arrows) reveals frequent apoptosis in M−/+ cells bordering WT cells (β-Gal-negative) (hsflp/+; FRT40, M(2), arm-lacZ/FRT40; actGal4, UAS mCD8 Parp Venus/+).(G and H) M−/+ posterior midgut harboring hs-Flp-induced WT clones (G and G′). Clones were left to grow for 4 days ACI and then TCFDN was expressed continually for 5–6 days across progenitor cells (PSwitchamp>TCFDN, +RU486) to induce ISC differentiation (hsflp/+; PSwitchAMP/UAS TCFDN; FRT82B, ubiGFP, RpS3/FRT82B). Clones were scored for the presence or absence of ISCs (scoring small DAPI+ cells as a proxy for ISCs) and further analyzed for the presence of Sytox+M−/+ cells at clone boundaries (arrows in G and G′) (n = 52 ISC− clones; n = 48 ISC+ clones). Differences in the distribution of clones between these two categories were not significantly different (p = 0.24, Fisher’s exact test) (H).Scale bars represent 50 μm. Genotypes are indicated in parentheses throughout the figure legends. Clones (defined in the z volume) are marked with dotted lines throughout the figures. See also Figure S1.
Mentions: Induction of death in weaker cells is a major hallmark of cell competition. To look for evidence of cell competition in the posterior midgut, we therefore asked whether wild-type intestinal cells induce accelerated turnover of neighboring M−/+ cells. Depending on the experiment, here and throughout this study, we induced either the formation of wild-type (M+/+) clones in a M−/+ gut or, vice versa, we generated M−/+ clones in a (pseudo) wild-type gut. Clones were induced in recently eclosed adults by heat shock-induced, Flp-mediated mitotic recombination. In the posterior midgut, cells that are turned over are shed into the intestinal lumen following epithelial delamination. Consistent with our hypothesis, we found that in mosaic guts containing wild-type and M−/+ cells, delaminated cells (normalized to the abundance of each cell population) were more likely to be M−/+ than wild-type (Figures 1A–1C). This indicated that in competing guts, M−/+ cells have an accelerated turnover compared to wild-type cells. However, although their relatively shorter lifetime could be a consequence of their interaction with wild-type cells, it could also result from the M−/+ mutation per se. To test the latter possibility, we compared relative turnover rates of wholly wild-type and wholly M−/+ posterior midguts using a previously published genetic tool that allows pulse labeling all cells in a gut and then chasing to monitor how long they persist (Jiang et al., 2009). This revealed that, in fact, cell turnover in M−/+ guts is slower than in wild-type guts (Figures S1A–S1D). This rules out the possibility that the accelerated turnover observed in competing guts is an intrinsic property of M−/+ cells and suggests that it is induced by cell competition. Next, we compared directly the relative cell-death frequency of M−/+ cells close to wild-type cells and of M−/+ cells far away (i.e., greater than two cell diameters away; see Experimental Procedures) from wild-type cells within the same guts using the cell-death marker Sytox (Figures 1D and 1E; Figures S1E–S1F″). Importantly, the cell-death frequency of M−/+ cells was specifically increased in the proximity of wild-type cells (Figures 1D and 1E), indicating that this was a result of cell-cell interaction. This finding was further confirmed by analysis of PARP cleavage (Figures 1F–1F″), a readout of caspase activation (Williams et al., 2006) (Figures S1E–S1F″), which also indicates that (at least some) cells die of apoptosis.

Bottom Line: Throughout their lifetime, cells may suffer insults that reduce their fitness and disrupt their function, and it is unclear how these potentially harmful cells are managed in adult tissues.We address this question using the adult Drosophila posterior midgut as a model of homeostatic tissue and ribosomal Minute mutations to reduce fitness in groups of cells.Finally, we show that winner cell proliferation is fueled by the JAK-STAT ligand Unpaired-3, produced by Minute(-/+) cells in response to chronic JNK stress signaling.

View Article: PubMed Central - PubMed

Affiliation: The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK.

Show MeSH
Related in: MedlinePlus