Journal: Neuron
Article Title: Astrocyte growth is driven by the Tre1/S1pr1 phospholipid-binding G protein-coupled receptor
doi: 10.1016/j.neuron.2023.11.008
Figure Lengend Snippet: (A) Images of spinal cord astrocyte membrane labeled with myrGFP (green) and nuclei labeled with H2AmCherry (magenta) in 6 dpf Tg(slc1a3b:myrGFP-P2A-H2AmCherry) transgenic control (N=15, dorsal view; N=3 lateral view) and s1pr1vo88/vo88 mutants (N=17, dorsal view; N=5, lateral view). N, number of animals. Scale bar, 20 µm. (B) Images of sparsely labeled individual astrocytes by slc1a3b:myrGFP-P2A-H2Amcherry DNA constructs and the representative IMARIS 3D-rendering surface (grey) at 6 dpf in the spinal cord of control and s1pr1vo88/vo88 mutant zebrafish. Scale bar, 20 µm. (C) Quantification of individual astrocyte volumes in control (N=18) and s1pr1vo88/vo88 mutants (N=23) at 6 dpf, related to (B). N, number of animals. Data points represent single astrocytes. ****, p<0.0001; unpaired t test. Error bars, mean values ± S.D. (D) Images of 6 dpf Tg(slc1a3b:myrGFP-P2A-H2AmCherry) larval brain in control (N=5) and s1pr1vo88/vo88 mutants (N=6). Dashed lines mark astrocyte processes densely infiltrated neuropil in the forebrain, midbrain, and hindbrain. N, number of animals. Scale bar, 50 µm. (E) Time-lapse still images of astrocyte process dynamics labeled with myrGFP (green) in control and s1pr1vo88/vo88 mutants at 3 dpf. Dashed boxes mark the regions shown to the right. Scale bar, 20 µm. (F) Quantification of astrocyte individual process extension and retraction displacement speed in control (N=10) and s1pr1vo88/vo88 mutants (N=8) at 3 dpf. N, number of animals. Data points represent single astrocyte processes tracked. *, p<0.05; ***, p<0.001; unpaired t test. Error bars, mean values ± S.D. (G and I) Images of 6 dpf Tg(slc1a3b:myrGFP-P2A-H2AmCherry) transgenic larval spinal cord astrocytes after treatment with DMSO, 1 µM FTY720, or 1 µM Ex26 at 2–4 dpf (G) or 4–6 dpf (I). Dashed boxes represent 4 independent 10 µm x 10 µm areas in the astrocyte process-enriched regions were used to quantify the GFP coverage area percentage. Scale bar, 20 µm. (H) Quantification of relative GFP coverage area percentage at 6 dpf in the astrocyte process-enriched regions in DMSO (N=12), FTY720 (N=12), and Ex26 (N=12) after 2–4 dpf treatment. N, number of animals. Data points represent average GFP coverage area percentage of the 4 independent areas in a single fish. ****, p<0.0001; one-way ANOVA with multiple comparisons. (J) Quantification of relative GFP coverage area percentage at 6 dpf in the astrocyte process-enriched regions in DMSO (N=10), FTY720 (N=12), and Ex26 (N=11) after 4–6 dpf treatment. N, number of animals. Data points represent average GFP coverage area percentage of the 4 independent areas in a single fish. ****, p<0.0001; one-way ANOVA with multiple comparisons. See also Figure S7 and Video S2.
Article Snippet: Acquired time-lapse images were Airyscan processed, and followed by Bleach correction and 3D drift correction using Fiji (ImageJ) software before analysis. . Chemical treatments FTY720 and Ex26 (Tocris Bioscience) were dissolved in DMSO to a stock concentration of 100 mM.
Techniques: Membrane, Labeling, Transgenic Assay, Control, Construct, Mutagenesis