Neurofibromatosis type 1-dependent alterations in mouse microglia function are not cell-intrinsic

ABSTRACT: We previously discovered a sex-by-genotype defect in microglia function using a germline heterozygous knockout mouse model of Neurofibromatosis type 1 (Nf1+/- mice), in which only microglia from male Nf1+/- mice exhibited defects in purinergic signaling. Herein, we leveraged an unbiased proteomic approach to demonstrate that male, but not female, heterozygous Nf1+/- microglia exhibit differences in protein expression, which largely reflect pathways involved cytoskeletal organization. In keeping with potential defects in cytoskeletal function, only male Nf1+/- microglia had reduced process arborization and surveillance capacity. Next, to determine whether these microglial defects were cell autonomous or reflected adaptive responses to Nf1 heterozygosity in other cells in the brain, we generated conditional microglia Nf1-mutant knockout mice by intercrossing Nf1flox/flox with Cx3cr1-CreER mice (Nf1flox/wt; Cx3cr1-CreER mice, Nf1MG+/- mice). Surprisingly, neither male nor female Nf1MG+/- mouse microglia had impaired process arborization or surveillance capacity. In contrast, when Nf1 heterozygosity was generated in neurons, astrocytes and oligodendrocytes by intercrossing Nf1flox/flox with hGFAP-Cre mice (Nf1flox/wt; hGFAP-Cre mice, Nf1GFAP+/- mice), the microglia defects found in Nf1+/- mice were recapitulated. Collectively, these data reveal that Nf1+/- sexually dimorphic microglia abnormalities are likely not cell-intrinsic properties, but rather reflect a response to Nf1 heterozygosity in other brain cells.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Brain, Microglial Cell

SUBMITTER: Oliver Popp  

LAB HEAD: Marcus Semtner

PROVIDER: PXD035881 | Pride | 2023-05-10

REPOSITORIES: Pride