Impact of Major Facilitator Superfamily Domain containing 2a (Mfsd2a) mediated lipid transport on oligodendrocyte lineage development at single cell level.

Mfsd2a is involved in transport of essential fatty acids such as docosahexaenoic acid (DHA) from the periphery across blood brain barrier (BBB) into the brain parenchyma. Loss of Mfsd2a in humans leads to microcephaly and hypomyelination. The significance of lipid species transported by Mfsd2a on oligodendrocyte lineage development is not known. Using OPC specific deletion of Mfsd2a (2aOKO) in mice we found that OPC cell state, differentiation and oligodendrocytes maturation is disrupted resulting in hypomyelination compared to 2afl/fl controls. Single cell RNAsequencing analysis was performed on total oligodendrocyte population from postnatal mouse brain using Ribo-TRAP mouse lines that labels complete oligodendrocyte lineage with GFP fluorescence to understand the influence of Mfsd2a on oligodendrocyte development. Overall design: Olig2-EGFP/Rpl10a (OL-Ribo-TRAP) BAC-transgenic mouse line from Jax, Stock # 030265 crossed to 2afl/fl and 2aOKO was used for the study. Total oligodendrocyte (OL) lineage population from postnatal day 8 mouse brain of 2afl/fl-OL-Ribo-TRAP (control) and 2aOKO-OL-Ribo-TRAP (OPC specific Mfsd2a knockout) were isolated using GFP fluorescence based flow cytometry. GFP positive cells from both these genotypes were analysed using single cell RNAsequencing.