Display Settings:

Items per page

Results: 7

1.
Figure 5

Figure 5. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hippo pathway regulates Dronc activity levels to control growth and apoptosis. Co-expression of Dark and proDronc with UASGFP (magenta in a) (GMR-Gal4 UASGFP, UASDark, UASproDronc) induces (a) Dronc (greyscale), and (b) activated Caspase 3 (Casp3*) in eyeantennal imaginal discs, resulting in development of small eyes in adult flies (c). The effect of co-expression of Dark and Dronc with Hpo (GMR-Gal4 UASHpo, UASDark, UASproDronc) (df) and Yki (GMR-Gal4 UASYki, UASDark, UASproDronc) (gi) on the expression of Dronc (d and g), and Casp3* (e and h) in eyeantennal imaginal discs and in adult eyes (f and i) is shown. Magnification and orientation of images is identical in all panels. The color reproduction of this figure is available at the Cell Death and Differentiation journal online

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
2.
Figure 2

Figure 2. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hpo overexpression induces Dronc. (ad) Wild-type expression of (a) diap1-lacZ, (b) DIAP1, (c) Hpo and (d) Dronc in third instar eyeantennal imaginal discs is shown. (eh) GMR-Gal4 UASHpo eyeantennal imaginal discs showing expression of (e) diap1-lacZ, (f) DIAP1, (g) Hpo and (h) Dronc, respectively. (i and j) Wild-type wing imaginal discs showing normal levels of expression of (i) Dronc and (j) Hpo-response element diap1-4.3GFP. nub-GAL4 UASHpo wing discs show no change in the expression of diap1-4.3GFP (green k, greyscale l), and show induction of Dronc (red k, greyscale m). (n) Wild-type third instar wing imaginal discs showing the domain of expression of nub-Gal4 marked by UAS GFP. (o) Semi-quantitative western blot to assess levels of expression of Dronc. Western blot analysis was performed on protein extracts from wild type (WT), GMR-Gal4 UASHpo and GMR-Gal4 UASproDronc eyeantennal imaginal discs. α-Tubulin is the loading control. Orientation of images is identical in ah (anterior to the right, dorsal up), and in im (anterior left). Yellow arrowheads mark the morphogenetic furrow that coincides with the boundary of the GMR-Gal4 expression domain

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
3.
Figure 1

Figure 1. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hpo overexpression induces cell death. (a) GMR-Gal4 UASGFP eyeantennal imaginal disc showing the GFP reporter expression in GMR domain in the eye disc. (bd) GMR-Gal4 UASHpo eye-antennal imaginal discs stained for (b) Hpo, (c) activated Drice (Drice*, red), Elav (green) and TOPRO (blue). Drice* marks dying cells in the eyeantennal discs (d, greyscale). (e and f) Mid-pupal retina (∼24APF) from GMR-Gal4 UASHpo animals showing ectopic cell death marked by expression of Drice* (e red, f greyscale), photoreceptor cells marked by Elav (e, blue), and cell shape marked by Discs large (Dlg) (e, green). (f) Ectopic cell death in the retina causes disruption of the retinal lattice. (g and h) Compared to wild type (g), the phenotype of Hpo over expressing retina (h) becomes progressively worse and results in the development of small rough eyes in the adult. (i) Wild-type mid-pupal retina comparable to retina in f marked by Drice*shows developmental apoptosis. (jl) Wild-type wing imaginal discs (j) from third instar larvae show very little Drice* expression, whereas wing imaginal discs from hsp70-Gal4 UASHpo animals (k and l) show robust induction of cell death as seen by activated Drice* expression (i, red) a few hours after Hpo activation. The orientation of images in a-i is anterior to the right and dorsal up, and the orientation of the wing imaginal discs(j and l) is anterior to left

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
4.
Figure 4

Figure 4. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hpo genetically interacts with Dronc to regulate organ size. A comparison of Dronc levels, mitotic figures and TUNEL-profiles in the GMR-Gal4 domain of eyeantennal imaginal discs from wild type, (df) GMR-Gal4 UASYki, (gi) GMR-Gal4 UASYki, UASproDronc and (kl) GMR-Gal4 UASproDronc animals is shown. Compared to wild type (a), Dronc levels are downregulated in cells overexpressing Yki (d). (b and c) Show a typical proliferation and cell death profile of wild-type eyeantennal imaginal discs, where cells undergo mitotic arrest posterior to the SMW (second mitotic wave) (b). Apoptosis is not induced at this stage of development (c). (e and f) In GMR-Gal4 UASYki eyeantennal discs the numbers of mitotic figures (PH3, e) are significantly increased in Yki overexpressing cells posterior to the SMW (e), and apoptosis is not induced (f). Co-expression of UASproDronc with UASYki causes a reduction in the number of mitotic figures posterior to SMW (h) and induces apoptosis (i). Control discs showing overexpression of UASproDronc stained for PH3 (k) and apoptosis (l) are shown for comparison. (j) Shows quantification of adult eye size from flies overexpressing UASYki alone or together with UASDNproDronc (P>0.05) or UASproDronc (P<0.05). Adult eye size was measured by counting the total number of ommatidia (n=5) for each genotype. Magnification and orientation of images is identical in all panels. The yellow arrows indicate the position of morphogenetic furrow that marks the boundary of the GMR-Gal4 domain. All comparisons are made in the region posterior (i.e. left) of the morphogenetic furrow. The color reproduction of this figure is available at the Cell Death and Differentiation journal online

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
5.
Figure 3

Figure 3. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hpo genetically interacts with Dronc to regulate cell death. Phenotypes of overexpression of GMR-Gal4 UASproDronc, (df) GMR-Gal4 UASHpo, (gi) GMR-Gal4 UASHpo UASproDronc, (jl) GMR-Gal4 UASDNproDronc and (mo) GMR-Gal4 UASHpo UAS DNproDronc are shown. A comparison of cell death induced by overexpression of each transgene is shown by expression of activated caspase 3 (Casp3*) antibody in third instar eyeantennal imaginal discs. (a, d and g) The resulting adult phenotype of caspase induction shows mild effects for overexpresssion of UASprodronc (a and b) that are enhanced by co-expression of UASHpo (g and h). Cell death induced by overexpression of UASHpo alone is shown in (d and e) for comparison. (jo) Overexpression of UASDNproDronc does not induce activated caspase (k) expression resulting in an almost wild-type adult eye phenotype (j). (mo) Co-expression of UASHpo and UASDNproDronc is unable to induce activated caspase (n) during third instar larval development resulting in a complete rescue of UASHpo-mediated apoptosis in the adult eye (compare m with d). (c, f, i, l and o) These panels show eyeantennal imaginal discs of the indicated genotypes stained for expression of Dronc to confirm overexpression of Dronc transgenes. Note that Dronc levels are upregulated by over expression of UASHpo (f). (pu) Wing imaginal discs from (pr) nub-Gal4 UASHpo, and (su) nub-Gal4 UASHpo UASDroncRNAi stained for Hpo (green) and apoptosis (TUNEL, red). nub-Gal4 UASHpo discs were identified by the upregulated levels of Hpo expression (green) in the nub-Gal4 domain using an antibody against Hpo. Note that the extensive cell death caused by Hpo over expression (q and r) is suppressed by downregulation of Dronc levels (t and u). However, downregulation of Dronc does not affect Hpo expression (compare q with t). The areas magnified in q, r, t, u are boxed in white in p and s. Orientation of images is identical in all panels

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
6.
Figure 6

Figure 6. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

dronc mutants show cell survival. (a and b) Shows comparison of wild-type and droncI29 adult mosaic eyes made using the cl w+ technique11 to compare proliferation rate of wild-type (red) and dronc mutant (white cells). Note that dronc mosaic eyes show fewer red cells, indicating that dronc mutant cells proliferate faster than wild-type cells. (cf) Analysis of clone sizes between GFP negative clones and their wild-type twin spots (GFP positive) for wild-type (c and d) and droncI24 mutants (e and f) are shown. Clone sizes were measured from wing imaginal discs dissected from mid third instar larvae. Representative twin clones from wild-type (d) and droncI24 (e) wing imaginal discs are shown for reference. (g-g″) droncI29 mutant clones (GFP negative) induce ectopic cell proliferation (PH3, red) posterior to the second mitotic wave in the eyeantennal disc. (g′ and g″) Higher magnification of the area boxed in g is shown in g′ to show extra cell proliferation in mutant clones. The PH3 expression is shown in greyscale in g″. (hj) Mid-pupal retinae from wild-type (h) wtsP2−/− (i) and dronc51−/− (j) mutants are shown. Cell outlines in mid-pupal retinae are marked using Dlg antibody. dronc mutant cells show survival of extra inter-ommatidial cells as marked by asterisks (see Figure 6j) The pigment cells for one wild-type (h) and one dronc mutant (j) ommatidium are numbered and marked by yellow lines. Magnification is identical for adult flies (a and b), imaginal discs (d, e, g′g″) and pupal retinae in hj. Imaginal discs in panels g is at a lower magnification (20 × )

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.
7.
Figure 7

Figure 7. From: Hippo signalling controls Dronc activity to regulate organ size in Drosophila.

Hippo regulates dronc transcription. Third instar eyeantennal imaginal discs from wild type (a-a″), GMR-Gal4 UASYki/dronc1.7 kb-lacZ (b-b″) and eyFLP; dronc1.7 kb-lacZ/+ FRT82 wtsX1/FRT82B UbiGFP (d-d″), larvae stained with α-β-gal to detect dronc1.7 kb-lacZ expression levels. (c) Quantification of dronc1.7 kb-lacZ levels measured by pixel intensity values of m β-gal expression in the GMR-Gal4 domain from eyeantennal imaginal discs of wild-type and GMR-Gal4 UAS Yki larvae (n=5, P<0.05). Third instar wing imaginal discs from wild-type (e) and nub-Gal4 UASHpo/ dronc1.7 kb−lacZ (f and f′) larvae stained with α β-gal to detect dronc1.7 kb−-lacZ expression levels. (g) Model for Hippo pathway mediated regulation of genes within the intrinsic cell death pathway. During homoeostasis, Diap1 restricts activation of caspases via proteosomal degradation. However, in many cells low levels of active apoptosome complexes are constantly generated in vivo by association of Dronc and Dark. Loss of function of Hippo pathway restricts Hid and Dronc expression and positively regulates Diap1 in living cells, which allows cells to proliferate and evade apoptosis. In naturally occurring cell death pathways that require Hippo activity, such as the killing of interommatidial cells, a death-inducing signal may activate Hpo, which in turn may induce expression and activation of Hid and Dronc, as well as downregulation of DIAP1 to trigger apoptosis. A similar scenario may be envisaged for other situations like stress (induced by overexpression of Hpo) that induce apoptotic response. The color reproduction of this figure is available at the Cell Death and Differentiation journal online

S Verghese, et al. Cell Death Differ. 2012 October;19(10):1664-1676.

Display Settings:

Items per page

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Write to the Help Desk