Systematic expression analysis of plasticity‐related genes in mouse brain development brings PRG4 into play. Issue 4 (16th October 2021) - Gross, Isabel
Abstract: Background: Plasticity‐related genes ( Prgs /PRGs) or lipid phosphate phosphatase‐related proteins (LPPRs) comprise five known members, which have been linked to neuronal differentiation processes, such as neurite outgrowth, axonal branching, or dendritic spine formation. PRGs are highly brain‐specific and belong to the lipid phosphate phosphatases (LPPs) superfamily, which influence lipid metabolism by dephosphorylation of bioactive lipids. PRGs, however, do not possess enzymatic activity, but modify lipid metabolism in a way that is still under investigation. Results: We analyzed mRNA expression levels of all Prgs during mouse brain development, in the hippocampus, neocortex, olfactory bulbs, and cerebellum. We found different spatio‐temporal expression patterns for each of the Prgs, and identified a high expression of the uncharacterized Prg4 throughout brain development. Unlike its close family members PRG3 and PRG5, PRG4 did not induce filopodial outgrowth in non‐neuronal cell lines, and does not localize to the plasma membrane of filopodia. Conclusion: We showed PRG4 to be highly expressed in the developing and the adult brain, suggesting that it is of vital importance for normal brain function. Despite its similarities to other family members, it seems not to be involved in changes of cell morphology; instead, it is more likely to be associated with intracellular signaling. Key Findings: Prg1, ‐2, ‐3 and ‐5 are dynamically expressed during mouse brain development Prg4 shows continuously high expression throughout development and in different brain areas Prgs are differentially expressed in glial cells Prg3 expression alters during oligodendrocyte maturation Unlike close family members, PRG4 does not induce filopodia outgrowth and is not localized to the filopodia plasma membrane