Spectrin regulates Hippo signaling by modulating cortical actomyosin activity
- Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, United States
Figures
Figure 1 with 2 supplements
Spectrins function synergistically with upstream regulators of Hippo signaling to control tissue growth.
(A–B) RNAi transgene against each of the three spectrin genes and UAS-wts were expressed separately or in combination in the wing tissue by nub-Gal4. Representative adult wings are shown. The graph …
Figure 1—figure supplement 1
Analysis of α-Spec and βH-Spec localization and RNAi knockdown efficiency in imaginal disc epithelial cells.
(A–C″) Third instar wing disc (A–B″) or eye disc (C–C″) containing GFP-positive MARCM clones with a-spec RNAi was stained for α-Spec protein (red). (B–B″) Shows a vertical section through the wing …
Figure 1—figure supplement 2
RNAi of βH-spec or β-spec, or a null allele of α-spec or β-spec, phenocopies the overgrowth phenotype of α-spec RNAi in pupal retina.
(A–B″) Pupal eye discs containing GFP-positive MARCM clones with βH-spec RNAi (A–A″) or β-spec RNAi (B–B″) were stained for DE-cad (red). The number on the lower left of A′ and B′ indicates the …
Figure 2 with 2 supplements
α-Spec regulates the expression of Hippo target genes.
(A–C′) Pupal eye discs containing GFP-positive MARCM clones with α-spec RNAi were stained for Ex (red, in A–B′) or ex-lacZ (red, in C–C′). B–B′ shows a vertical section through the eye disc in A–A′, …
Figure 2—figure supplement 1
α-Spec regulates the expression of Hippo target genes.
(A–C″) Third instar wing discs expressing GFP or α-spec RNAi in the posterior compartment with engrailed (en)-Gal4 were stained for Ex (A–B″) or ex-lacZ (C–C″). Dashed lines indicate …
Figure 2—figure supplement 2
Loss of α-Spec does not affect the subcellular localization of Mer or Kibra.
(A–B″) A pupal eye disc containing GFP-positive MARCM clones with α-spec RNAi was stained for Mer (red). (B–B″) shows a vertical section through the eye disc in A–A′, in which the position of the …
Figure 3
Loss of spectrin promotes the phosphorylation and activation of MLC.
(A–F′) Pupal eye discs containing GFP-positive MARCM clones with α-spec, βH-spec, or β-spec RNAi were stained for phospho-MLC (p-MLC, red). For each imaginal disc, both apical section (A–A′, C–C′ …
Figure 4
Canonical upstream tumor suppressors of the Hippo pathway do not regulate p-MLC activity.
(A–E′) Pupal eye discs containing GFP-positive MARCM clones of the indicated mutations were stained for p-MLC. Note the similar levels of p-MLC inside and outside the mutant clones. (F–F‴) A pupal …
Figure 5 with 1 supplement
Inhibition of MLC activation suppresses the α-spec-deficient phenotypes.
(A–D) Pupal eye discs containing GFP-positive MARCM clones of the indicated genotypes. Note the increased clone size resulting from α-spec RNAi (compare the relative representation of GFP-positive …
Figure 5—figure supplement 1
Loss of α-Spec does not affect the subcellular localization of Jub or Wts.
(A–A″) A third instar wing disc containing GFP-positive MARCM clones with α-spec RNAi was stained for Wts-V5 (red). Note the similar level and localization of Wts-V5 inside and outside the mutant …
Figure 6
Myosin II-regulated cytoskeletal tension functions in parallel with the canonical upstream tumor suppressors to regulate Hippo signaling.
(A–F) The synergistic effect of myosin II activation and loss of Ex or Mer on interommatidial cell number. Pupal eye discs of the indicated genotype were stained for DE-cad. 20 ommatidial clusters …
Figure 7
Loss of SPTAN1 results in decreased YAP phosphorylation, increased YAP nuclear localization, and increased cortical p-MLC level in MCF10A cells.
(A–B‴) Confluent cultures of MCF10A cells treated with control RNAi or SPTAN1 RNAi were stained for YAP (green), actin (red) and the nuclear dye DAPI (blue). Note the increased nuclear YAP signal in …
