Notch inhibition affects progenitor division patterns. (A) Onset of Ath5 expression (green) in Ath5+ progenitors between divisions. (B) Example of Ath5- sister cell followed to next division. hsp70:H2B-RFP (nuclei, grey), ath5:GFP-CAAX (Ath5, green). Scale bar, 10 μm. (C) Schematics of lineage tree of Ath5- cell. (D) Ath5+ cells (grey) at 36 hpf in control (left) and upon Notch inhibition (right) with DAPT 50 μM. Scale bar, 50 μm. The yellow line delimits the apical side of the retinal neuroepithelium. (E) EdU+ cells (grey) at 42 hpf in control (left) and upon Notch inhibition (right) treated with 10 μM LY411575. Scale bar, 50 μm. The yellow lines delimit the apical and basal side of the retinal neuroepithelium. (F) Quantification of EdU-positive cells in the central portion of the retina in control (black) and upon Notch inhibition (blue). Unpaired t-test with Welch’s correction. Error bars represent standard deviation.

Notch inhibition affects progenitor division patterns. (A) Onset of Ath5 expression (green) in Ath5+ progenitors between divisions. (B) Example of Ath5- sister cell followed to next division. hsp70:H2B-RFP (nuclei, grey), ath5:GFP-CAAX (Ath5, green). Scale bar, 10 μm. (C) Schematics of lineage tree of Ath5- cell. (D) Ath5+ cells (grey) at 36 hpf in control (left) and upon Notch inhibition (right) with DAPT 50 μM. Scale bar, 50 μm. The yellow line delimits the apical side of the retinal neuroepithelium. (E) EdU+ cells (grey) at 42 hpf in control (left) and upon Notch inhibition (right) treated with 10 μM LY411575. Scale bar, 50 μm. The yellow lines delimit the apical and basal side of the retinal neuroepithelium. (F) Quantification of EdU-positive cells in the central portion of the retina in control (black) and upon Notch inhibition (blue). Unpaired t-test with Welch’s correction. Error bars represent standard deviation.

(A) Maximum basal position of Ath5- and Ath5+ cells. Unpaired t-test with Welch’s correction. (B) Integral mean of Ath5- and Ath5+ cells. Vertical bars represent standard deviation. Kolmogorov-Smirnov test. (C) Directionality ratio of Ath5+ and Ath5- progenitors cell soma for basal translocation. Data from Figure 2D–E. Error bars represent SEM. (D) Average velocity of Ath5+ and Ath5- cell bodies between 0 and 100 min, corresponding to basal translocation. Vertical bars represent standard deviation. Unpaired t-test. (E) Comparison between maximum basal position of sister cells in control (purple dots) and dynactin dominant negative (dynactin DN, cyan dots) from Figure 2B and K, respectively. Line connects sister cells.

Figure 2—figure supplement 1—source data 1.

(A) Maximum basal position of Ath5- and Ath5+ cells. Unpaired t-test with Welch’s correction. (B) Integral mean of Ath5- and Ath5+ cells. Vertical bars represent standard deviation. Kolmogorov-Smirnov test. (C) Directionality ratio of Ath5+ and Ath5- progenitors cell soma for basal translocation. Data from Figure 2D–E. Error bars represent SEM. (D) Average velocity of Ath5+ and Ath5- cell bodies between 0 and 100 min, corresponding to basal translocation. Vertical bars represent standard deviation. Unpaired t-test. (E) Comparison between maximum basal position of sister cells in control (purple dots) and dynactin dominant negative (dynactin DN, cyan dots) from Figure 2B and K, respectively. Line connects sister cells.

Figure 2—figure supplement 1—source data 1.

(A) Notch1b staining of 36 hpf embryos injected with control-MO (upper row), notch1b-MO 1 ng/embryo (middle row) and notch1b-MO 2 ng/embryo (lower row). Dashed lines indicate apical and basal sides of the retinal neuroepithelium. Scale bar, 30 μm. DAPI labels nuclei (grey). (B) DeltaC staining of 36 hpf embryos injected with control-MO (upper row), deltaC-MO1 (middle row) and deltaC-MO2 (lower row). Dashed lines indicate apical and basal side of the retinal neuroepithelium. Scale bar, 30 μm. DAPI labels nuclei (grey). (C) Staining 36 hpf embryos for Notch1b in the tail. Arrowheads indicate positive staining of somites. Scale bar, 50 μm. DAPI labels nuclei (grey).

(A) Notch1b staining of 36 hpf embryos injected with control-MO (upper row), notch1b-MO 1 ng/embryo (middle row) and notch1b-MO 2 ng/embryo (lower row). Dashed lines indicate apical and basal sides of the retinal neuroepithelium. Scale bar, 30 μm. DAPI labels nuclei (grey). (B) DeltaC staining of 36 hpf embryos injected with control-MO (upper row), deltaC-MO1 (middle row) and deltaC-MO2 (lower row). Dashed lines indicate apical and basal side of the retinal neuroepithelium. Scale bar, 30 μm. DAPI labels nuclei (grey). (C) Staining 36 hpf embryos for Notch1b in the tail. Arrowheads indicate positive staining of somites. Scale bar, 50 μm. DAPI labels nuclei (grey).

(A) Example of Ath5+ cell (cyan) that does not express Tp1 (magenta). Dashed line outlines cell body. Scale bar, 10 μm. (A’) Example of Ath5+ cell (cyan) that expresses weak Tp1 signal (magenta). Dashed line outlines cell body. Scale bar, 10 μm. (B) Three different 36 hpf embryos showing Tp1-positive cells (magenta) that carry Sara-positive endosomes (cyan). White arrowheads indicate Sara endosomes. Scale bar, 10 μm. DAPI labels nuclei (grey). 

Stathmin is labelled by hsp70:Stathmin1-mKate2 (grey) and Ath5 expression is followed using ath5:GFP-CAAX (green). Time is shown in hours and minutes. Yellow and magenta dots label Ath5+ and Ath5- sister cell, respectively.

(A) Ath5+ cells (grey) in the retinal neuroepithelium at 36 hpf in embryos injected with control-MO (upper row) and 2.5 ng/embryo Sara-MO (lower row). Scale bar, 50 μm. The yellow lines delimit the apical and basal side of the retinal neuroepithelium. (B) pH3 staining (cyan) in 36 hpf Tg(ath5:gap-GFP) embryos (grey) injected with control-MO (upper row) and 2.5 ng/embryo Sara-MO (lower row). Scale bar, 50 μm. The yellow lines delimit the apical side of the retinal neuroepithelium. (C) EdU+ cells (grey) at 36 hpf in control (upper row) and upon Sara knockdown (lower row) in Tg(ath5:gap-GFP) embryos (green). Scale bar, 50 μm. (D) Quantification of EdU-positive cells in the central portion of the retina in control (black) and Sara knockdown (blue). Unpaired t-test with Welch’s correction. Error bars represent standard deviation. (E) Example of an asymmetric inheritance of Sara-positive endosomes (left) within asymmetric division of multipotent progenitors generating Ath5+ progenitors (right). hsp70:mkate2-ras (cells membrane, grey), CFP-Sara (Sara-positive endosomes, cyan), ath5:GFP-CAAX (Ath5, green). Dashed lines show apical and basal sides of the retinal neuroepithelium. Scale bar, 10 μm. Magenta and yellow dots label sister cells. White arrow points to the Sara-positive endosome.

(A) Ath5+ cells (grey) in the retinal neuroepithelium at 36 hpf in embryos injected with control-MO (upper row) and 2.5 ng/embryo Sara-MO (lower row). Scale bar, 50 μm. The yellow lines delimit the apical and basal side of the retinal neuroepithelium. (B) pH3 staining (cyan) in 36 hpf Tg(ath5:gap-GFP) embryos (grey) injected with control-MO (upper row) and 2.5 ng/embryo Sara-MO (lower row). Scale bar, 50 μm. The yellow lines delimit the apical side of the retinal neuroepithelium. (C) EdU+ cells (grey) at 36 hpf in control (upper row) and upon Sara knockdown (lower row) in Tg(ath5:gap-GFP) embryos (green). Scale bar, 50 μm. (D) Quantification of EdU-positive cells in the central portion of the retina in control (black) and Sara knockdown (blue). Unpaired t-test with Welch’s correction. Error bars represent standard deviation. (E) Example of an asymmetric inheritance of Sara-positive endosomes (left) within asymmetric division of multipotent progenitors generating Ath5+ progenitors (right). hsp70:mkate2-ras (cells membrane, grey), CFP-Sara (Sara-positive endosomes, cyan), ath5:GFP-CAAX (Ath5, green). Dashed lines show apical and basal sides of the retinal neuroepithelium. Scale bar, 10 μm. Magenta and yellow dots label sister cells. White arrow points to the Sara-positive endosome.