Profiling of Sexually Dimorphic Genes in Neural Cells to Identify Eif2s3y, Whose Overexpression Causes Autism-Like Behaviors in Male Mice

Abstract

Many neurological disorders exhibit sex differences and sex-specific therapeutic responses. Unfortunately, significant amounts of studies investigating molecular and cellular mechanisms underlying these neurological disorders use primary cell cultures with undetermined sexes; and this may be a source for contradictory results among different studies and impair the validity of study conclusion. Herein, we comprehensively compared sexual dimorphism of gene expression in primary neurons, astrocytes, and microglia derived from neonatal mouse brains. We found that overall sexually dimorphic gene numbers were relatively low in these primary cells, with microglia possessing the most (264 genes), neurons possessing the medium (69 genes), and astrocytes possessing the least (30 genes). KEGG analysis indicated that sexually dimorphic genes in these three cell types were strongly enriched for the immune system and immune-related diseases. Furthermore, we identified that sexually dimorphic genes shared by these primary cells dominantly located on the Y chromosome, including Ddx3y, Eif2s3y, Kdm5d, and Uty. Finally, we demonstrated that overexpression of Eif2s3y increased synaptic transmission specifically in male neurons and caused autism-like behaviors specifically in male mice. Together, our results demonstrate that the sex of primary cells should be considered when these cells are used for studying the molecular mechanism underlying neurological disorders with sex-biased susceptibility, especially those related to immune dysfunction. Moreover, our findings indicate that dysregulation of sexually dimorphic genes on the Y chromosome may also result in autism and possibly other neurological disorders, providing new insights into the genetic driver of sex differences in neurological disorders.

Neurexin-3 defines synapse- and sex-dependent diversity of GABAergic inhibition in ventral subiculum

“…Our scRNA-seq revealed six protein-coding genes that are upregulated in male compared to female vSUB PV neurons, that is, Ddx3y, Eif2s3y, Vip, Penk, Dkk3, and Plp1, and one gene upregulated in female PVs, Gstm1 ( Figures 7G and 7H ). Ddx3y (DEAD-box helicase 3y) and Eif2s3y (eukaryotic translation initiation factor) are Y-linked genes involved in translation and may contribute to neuronal differentiation (Ddx3y) and synaptic transmission (Eif2s3y; Zhang et al, 2021 ) in male mice. The secreted glycoprotein Dkk3 (Dickkopf-3) is a negative modulator of Wnt signaling and may play a role in neuron differentiation in development and have a neuroprotective role after development ( Busceti et al, 2018 ).…”

Gene therapy using human FMRP isoforms driven by the human FMR1 promoter rescues fragile X syndrome mouse deficits

“…Primary neurons, astrocytes, and microglia were derived from neonatal WT mice as described previously. 30 …”

Pedigree-based study to identify GOLGB1 as a risk gene for bipolar disorder

“…Primary neurons were derived from postnatal day 0 (P0) mouse brains as described previously [ 43 ]. Briefly, hippocampal and cortical tissues were removed from the P0 mouse brain and then dissociated with 0.25% trypsin and DNase I (0.2 kU/mL, Worthington) at 37 °C for 15 min.…”

“…Data were recorded and analyzed using the Smart 3.0 video tracking system (Panlab, Harvard Apparatus). Procedures for the open field test, the tail suspension test, the elevated plus-maze test, the three-chamber social interaction test, the Y-maze test, and the novel object recognition test were reported previously [ 43 , 44 ]. Procedures for other behavioral tests were as the following.…”