Fig. 1. LDs are highly abundant in NSPCs under physiological conditions.
a Schematic illustration of an LD, showing the TAG- and CE-containing core, surrounded by a monolayer of phospholipids and LD coat proteins. b qRT-PCR analysis showing that Plin2 is the most abundant of the five Plin family members expressed in proliferating SVZ NSPCs (n = 3 samples, fold change versus Plin1 ± SEM, one-way ANOVA with Dunnett’s multiple comparisons correction, adj. p-values: Plin2 < 0.0001, Plin3 = 0.0001, Plin4 = 0.0113, Plin5 = 0.0004). c Co-staining with the neutral lipid dye BD493 in proliferating SVZ NSPCs shows that >90% of BD493 positive LDs are also PLIN2-positive. Representative images are maximum intensity projections of the individual channels and a merge. (n = 520 cells from 3 coverslips, mean ± SEM). d Staining against PLIN2 (white) show a large variability in LD numbers and volume among proliferating SVZ NSPCs. Representative images are maximum intensity projections. Results were similar among 45 images from 3 coverslips. e Quantification of LD number, volume and diameter using 3D-single-cell reconstructions confirms the variability shown in d. (n = 130 cells from 3 coverslips). Each dot represents a single cell. LD diameters are shown as a violin plot. f Analysis of existing single-cell RNA-seq data27,28 from the adult SVZ niche cells shows that Plin2 mRNA is expressed in astrocytes and NSPCs (the original nomenclature of the clusters was kept, thus here called aNSCs, TAC and NB). A UMAP showing unsupervised clustering and a feature plot for Plin2 in astrocytes and NSPCs. g Expression analysis in the different clusters shows that Plin2 expression is highest in NSPCs. h In situ hybridization using RNAscope shows Plin2 expression (white) in GFP-positive cells (green) in the ventricular zone/SVZ of brain sections from NestinGFP mice. Representative maximum intensity projections. Results were similar among n = 3 mice. Nuclei (blue) are stained with DAPI. i Immunohistochemical staining against PLIN2 protein (white) in the SVZ of a NestinGFP mouse (green) shows that LDs are present in this region. Representative images are maximum intensity projections. Results were similar among n = 3 mice. Asterisks indicate the following p-values: * < 0.05; *** < 0.001.