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Abstract Background KDM6A is a demethylase encoded by a gene with female-biased expression due to escape from X inactivation. Its main role is to facilitate gene expression through removal of the repressive H3K27me3 mark, with evidence of some additional histone demethylase-independent functions. KDM6A mutations have been implicated in congenital disorders such as Kabuki Syndrome, as well as in sex differences in cancer. Methods Kdm6a was knocked out using CRISPR/Cas9 gene editing in F1 male and female mouse embryonic stem cells (ES) derived from reciprocal crosses between C57BL6 x Mus castaneus . Diploid and allelic RNA-seq analyses were done to compare gene expression between wild-type and Kdm6a knockout (KO) clones. The effects of Kdm6a KO on sex-biased gene expression were investigated by comparing gene expression between male and female ES cells. Changes in H3K27me3 enrichment and chromatin accessibility at promoter regions of genes with expression changes were characterized by ChIP-seq and ATAC-seq followed by diploid and allelic analyses. Results We report that Kdm6a KO in male and female embryonic stem (ES) cells derived from F1 hybrid mice cause extensive gene dysregulation, disruption of sex biases, and specific parental allele effects. Among the dysregulated genes are candidate genes that may explain abnormal developmental features of Kabuki syndrome caused by KDM6A mutations in human. Strikingly, Kdm6a knockouts result in a decrease in sex-biased expression and in preferential downregulation of the maternal alleles of a number of genes. Most promoters of dysregulated genes show concordant epigenetic changes including gain of H3K27me3 and loss of chromatin accessibility, but there was less concordance when considering allelic changes. Conclusions Our study reveals new sex-related roles of KDM6A in the regulation of developmental genes, the maintenance of sex-biased gene expression, and the differential expression of parental alleles.
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Gordon Holmes syndrome model mice exhibit alterations in microglia, age and sex-specific disruptions in cognitive and proprioceptive function
Gordon Holmes syndrome (GHS) is a neurological disorder associated with neuroendocrine, cognitive, and motor impairments with corresponding neurodegeneration. Mutations in the E3 ubiquitin ligaseRNF216are strongly linked to GHS. Previous studies show that deletion ofRnf216in mice led to sex-specific neuroendocrine dysfunction due to disruptions in the hypothalamic-pituitary-gonadal axis. To address RNF216 action in cognitive and motor functions, we testedRnf216knockout (KO) mice in a battery of motor and learning tasks for a duration of one year. Although male and female KO mice did not demonstrate prominent motor phenotypes, KO females displayed abnormal limb clasping. KO mice also showed age-dependent strategy and associative learning impairments with sex-dependent alterations of microglia in the hippocampus and cortex. Additionally, KO males but not females had more negative resting membrane potentials in the CA1 hippocampus without any changes in miniature excitatory postsynaptic current (mEPSC) frequencies or amplitudes. Our findings show that constitutive deletion ofRnf216alters microglia and neuronal excitability, which may provide insights into the etiology of sex-specific impairments in GHS. Significance StatementGordon Holmes syndrome (GHS) is a rare neurological disorder associated with neuroendocrine, cognitive, and motor impairments with corresponding neurodegeneration. Although mutations inRnf216have been identified in male and female GHS individuals, it has yet to be tested if removal ofRnf216causes cognitive and motor dysfunction. This study characterizes motor and learning behaviors in male and female GHS model mice. We find that deletion ofRnf216does not disrupt motor function but does lead to sex-specific effects on proprioceptive and age-dependent changes in cognitive behaviors. Our study provides new insight into how disruptions inRnf216contribute to the emergence of sex-specific phenotypes in individuals with GHS.
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- Award ID(s):
- 2047700
- PAR ID:
- 10483695
- Publisher / Repository:
- Society for Neuroscience
- Date Published:
- Journal Name:
- eneuro
- ISSN:
- 2373-2822
- Page Range / eLocation ID:
- ENEURO.0074-23.2023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1523/ENEURO.0074-23.2023
