IMAGE

Fig. 8

ID
ZDB-IMAGE-160927-36
Source
Figures for Liu et al., 2016
Image
Figure Caption

Fig. 8

The endocytic trafficking defects of Activin/Nodal type I receptor ALK4 in MZfscn1a mutants.

(a,b) 20 pg ALK4-GFP mRNA was injected into one blastomere of a 16-cell wild-type or MZfscn1a embryo. Embryos were harvested at shield stage and costained with phalloidin-TRITC and anti-GFP antibody to show the co-localization of F-actin (red) and ALK4 (green). GFP-positive hypoblast cells were selected and photoed using a Nikon A1R+ confocal microscope. The boxed area in the left image (Scale bar, 10 µm) is presented at a higher magnification in the corresponding right image (Scale bar, 2 µm) (a). Peason’s co-localization coefficient was quantified from the indicated cell numbers in three independent experiments and the group values are expressed as mean±s.d. Student’s t-test, *P<0.05 (b). (c) Immunostaining images of Rab5-RFP (red) and ALK4-GFP (green) in hypoblast cells of wild-type or MZfscn1a embryos. 20 pg ALK4-GFP mRNA and 20 pg Rab5-RFP mRNA were co-injected into one blastomere of a 16-cell wild-type or MZfscn1a embryo. Embryos were collected at shield stage for immunostaining with anti-GFP and anti-dsRed antibodies. Scale bar, left images, 10 µm; right images, 3 µm. (d) Peason’s co-localization coefficient of ALK4-GFP and Rab5-RFP was quantified from the indicated cell numbers in three independent experiments and the group values are expressed as mean±s.d. *P<0.05. (e) Proposed mechanism of the function of Fscn1 in trafficking and signalling of TGF-β type I receptors. TGF-β/Smad signal induces the expression of fscn1 gene and Fscn1 protein acting as a molecular linker between TGF-β family type I receptors and the actin cytoskeleton, which promotes the trafficking of internalized receptors from clathrin-coated vesicles to early endosomes, thereby enhancing TGF-β signal activity. TβRII, TGF-β type II receptor; CCP, clathrin-coated pit; AP2, assembly polypeptide 2.

Acknowledgments
This image is the copyrighted work of the attributed author or publisher, and ZFIN has permission only to display this image to its users. Additional permissions should be obtained from the applicable author or publisher of the image. Full text @ Nat. Commun.