Figure 4: Borcs6 is necessary for proper endo-lysosomal function in the developing embryo.

IF analysis of E-cadherin (green), Rab7 (red), Lamp1 (white) and nuclei counterstained with DAPI (blue) in E6.5 control littermate (A) and mutant embryo (B) (scale bar: 50 μm). Insets in (A) and (B) are magnified in (C) and (D), respectively (scale bar: 20 μm). Individual channels are shown for Rab7 (C’, D’), and Lamp1 (C”, D”). (C”’) and (D”’) show a merged image of Rab7 and Lamp1.

(E-E”’ and F-F”’) Maximum intensity projections of confocal images illustrate localization of Rab7 (red), Lamp1 (white) and nuclei stained with DAPI (blue) in control and mutant E6.5 embryos (scale bar: 50 μm). Inset boxes are magnified in (G) and (H).

Sagittal optical section illustrating internalization of dextran-647 (white) in control (I) and mutant (J) embryos after 10-minute wash in the absence of dextran-647. Maximum intensity projections are shown in (I’) and (J’). Images were also collected after 45-minute incubation in the absence of dextran-647 (K-K’, L-L’). After 65 minutes of incubation, embryos were fixed, and immunofluorescence was conducted. Optical sections of the dextran are shown in (M) and (N), while maximum intensity projection is depicted in (M’) and (N’), respectively. (M”) and (N”) are maximum intensity projections with both dextran (white) and nuclei counterstained with DAPI (blue). Scale bar: 50 μm