Pentagone internalises glypicans to fine-tune multiple signalling pathways
- Albert-Ludwigs-University of Freiburg, Germany
Figures
Figure 1 with 4 supplements
Pent internalises Dally.
(A) Localisation of DallyYFP in a WT third instar wing disc. Solid and dashed lines indicate the AP and DV boundaries respectively. (B) Expression of UASV5Pent with apGal4 internalised DallyYFP into …
Figure 1—figure supplement 1
Excessive Dally traps Dpp.
(A–C) WT (A) and disc expressing DallyGFP in the Dpp stripe (B) immunostained for pMad. Expression of Dally in the Dpp stripe increases pMad in the centre of the disc at the expense of the …
Figure 1—figure supplement 2
Binding interactions and distribution of Pent.
(A) Schematic diagram of wing disc, where UAS constructs are expressed with apgal4 (green) and LexOV5Pent from the dpp stripe (dppLexA). (B–F) Third instar wing discs expressing UASGFP (B), …
Figure 1—figure supplement 3
Endogenously tagged BMP signalling components are fully functional.
(A–H) Adult wing and anterior wing margin morphology (for A–F) from flies of the indicated genotypes. Scale bars are shown in (A) and are 500 µm and 100 µm for wing and wing margin, respectively. A …
Figure 1—figure supplement 4
Pent and DallyYFP co-localise at endogenous levels.
(A) Third instar DallyYFP wing disc immunostained for Pent. Pent and DallyYFP localise together in discrete puncta. (B,C) Third instar wing discs expressing UASV5Pent with apGal4. Immuno-staining …
Figure 2 with 3 supplements
Pent internalises the second D. melanogaster glypican, Dally-like protein.
(A) Localisation of Dlp in a WT third instar wing disc. (B) Expression of UASV5Pent with enGal4 resulted in a decrease of Dlp protein in the posterior compartment and co-localisation of Dlp with …
Figure 2—figure supplement 1
Dlp expression is not repressed by Dpp signalling.
Inhibition of Dpp signalling in Mad mutant clones up-regulates the Dpp repressed gene brk, but does not increase Dlp protein level, suggesting that Dlp is not repressed by Dpp signalling. Scale bars …
Figure 2—figure supplement 2
Pent in the dorsal compartment reduces Dpp accumulation and affects pMad gradient formation.
(A–B) Third instar wing disc expressing LexOeGFPDpp under control of DppLG, immunostained for extracellular GFP to visualise spreading of Dpp. Expression of V5Pent in the dorsal compartment with …
Figure 2—figure supplement 3
Dpp, Notum and Shf do not internalise DallyYFP.
(A–C) Third instar wing discs expressing UASDppHA (A), UASNotumV5 (B) or UASShfV5 (C) with apGal4. No reduction in DallyYFP is seen in any condition. Lower panels are enlargements of indicated …
Figure 3 with 1 supplement
Internalisation of glypicans by Pent is signalling independent.
(A) Localisation of TkvHA in a WT third instar wing disc. (B) UASV5Pent expressed with apGal4 co-localised with TkvHA in puncta, but no reduction in TkvHA protein level was seen. Arrows show …
Figure 3—figure supplement 1
Internalisation of Dally by Pent does not require the receptor.
(A) Wing disc expressing UASV5Pent with apGal4, in a background of TkvHA and DallyYFP. Lower panels are enlargements of boxed regions. Arrows indicate Dally, Tkv and Pent co-localisation. (B) Wing …
Figure 4 with 1 supplement
The endocytic route of V5Pent and DallyYFP.
(A) Control third instar wing disc expressing LexOV5Pent with DppLHV1 LexA driver. Reduction of DallyYFP is seen in both dorsal (above dashed line) and ventral (below dashed line) regions of the …
Figure 4—figure supplement 1
Endocytosis of Pent and Dally is clathrin and LRP1 independent.
(A) Two examples of wing discs expressing UASchcRNAi in the dorsal compartment at the Gal80ts restrictive temperature of 30°C for 24 hr. Substantial reduction in fluorescence is seen when …
Figure 5 with 1 supplement
Pent modifies Wg signalling.
(A) Adult wings of WT (left) and pent△2–5 (right). 9% of pent△2–5 wings have defects in the wing margin (n=35). Scale bar is 500 µm. (B) Adult wings of wild type (upper image) and pent△2–5 (lower …
Figure 5—figure supplement 1
Pent modifies expression of the Wg target gene Sens.
(A–C) Control disc (A), or discs expressing DlpGFP with either V5Pent (C) or △SPV5Pent (B), which is non-functional and included to ensure equal number of UAS constructs. Expression of Pent …
Figure 6
Model for Pent´s function in BMP signalling.
Pent binds to glypicans and induces their signal-independent internalisation and lysosomal degradation. In the absence of Pent (left), glypican levels on cell surfaces increase. Elevated co-receptor …
Author response image 1
Author response image 2
