Fig. 2: Apocrine secretion alters the embryonic CSF proteome.
From: Choroid plexus apocrine secretion shapes CSF proteome during mouse brain development
a, Volcano plot showing differences in protein abundance between E16.5 CSF at baseline and following apocrine secretion. Proteins with P values less than 0.05 appear above the horizontal dashed line. The vertical dashed lines indicate the threshold of ±1.1 fold change (FC); N = 3 pooled litters per condition. b, Experimental schematic for data presented in c and d. c, Enzyme-linked immunosorbent assay (ELISA) of explant-conditioned aCSF for IGF-2. Each point represents aCSF conditioned by five E16.5 ChP explants; LV N = 14, 3V N = 7, 4V N = 7. d, ELISA of explant-conditioned aCSF for SHH. Each point represents aCSF conditioned by five E16.5 ChP explants; LV N = 6, 3V N= 5, 4V N = 6. e, ELISA of explant-conditioned aCSF for insulin. Each point represents aCSF conditioned by five E16.5 ChP explants; LV N = 5, 3V N = 5, 4V N = 5. f, Biological pathways identified by GSEA for proteins released in vivo by ChP 5-HT2C-evoked secretion. A one-sided, right-tailed Fisher’s exact test was used to assess over-representation of pathways (P < 0.05), as our analysis focused specifically on identifying enrichment in the observed direction of change; ns, not significant (P > 0.05); *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ****P ≤ 0.0001. g,h, IPA of ChP in vivo secreted proteins demonstrated activation of proliferation- and development-related pathways (g) and activation of neuronal survival, neurite outgrowth and synapse development pathways and inhibition of neuronal apoptosis (h). i, Left: Nissl annotation from the Allen Developing Mouse Brain Reference Atlas69 (developingmouse.brain-map.org). Confocal images of phosphorylated AKT (pAKT) in E14.5 neural progenitor cells (center) and quantification of pAKT fluorescence intensity (right) are also shown (control N = 11, three litters; WAY-161503 N = 8, three litters); scale bars, 20 µm. All data are presented as mean ± s.e.m. P values were calculated by one-way ANOVA with a Tukey correction for c–e, a one-sided Fisher’s exact test for f and a two-tailed t-test for i. Panel b created with BioRender.com.
