Dataset Information

Aberrant H3.3 dynamics in NAc promote vulnerability to depressive-like behavior

ABSTRACT: Human major depressive disorder (MDD), along with related mood disorders, is among the world’s greatest public health concerns, however, its pathophysiology remains poorly understood. Persistent changes in gene expression are known to promote physiological aberrations implicated in MDD. More recently, histone mechanisms affecting cell-type and regional specific chromatin structures have also been shown to contribute to transcriptional programs related to depressive behaviors, as well as responses to antidepressants (ADs). Although much emphasis has been placed in recent years on roles for histone posttranslational modifications (PTMs) and chromatin remodeling events in the etiology of MDD, it has become increasingly clear that replication-independent histone variants (e.g., H3.3), which differ in primary amino acid sequence from their canonical counterparts, similarly play critical roles in the regulation of activity-dependent neuronal transcription, synaptic connectivity and behavioral plasticity. Here, we demonstrate a novel role for increased H3.3 dynamics in nucleus accumbens (NAc)––a key limbic brain reward region––in the regulation of aberrant social stress-mediated gene expression, abnormal dendritic morphology and the precipitation of depressive-like behaviors in mice. We find that molecular blockade of these dynamics promotes resilience to chronic social stress and results in a partial re-normalization of stress-associated transcriptional patterns in NAc. In sum, our findings establish H3.3 dynamics as a critical, and previously undocumented, regulator of mood, and suggest that future therapies aimed at modulating striatal histone dynamics may potentiate beneficial behavioral adaptations to negative emotional stimuli.

ORGANISM(S): Mus musculus

PROVIDER: GSE85900 | GEO | 2017/02/08

SECONDARY ACCESSION(S): PRJNA339713

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Despite depression being one of the most prevalent and debilitating disorders worldwide, it has been difficult to understand its pathophysiology and to develop more effective treatments. Maladaptive transcriptional regulation within limbic neural circuits, including reward processing regions such as the nucleus accumbens (NAc), in response to chronic stress is thought to be a major contributor to the development of the syndrome. Epigenetic events?in particular, histone writers and erasers?that alter chromatin structure to regulate programs of gene expression have increasingly been associated with depression-related behavioral abnormalities in animal models and in depressed humans examined postmortem. However, very little is known about the ATP-dependent chromatin remodelers that control nucleosome positioning and the packing state of chromatin. Here we show that the ACF complex, part of the ISWI family of chromatin remodelers, is persistently and selectively upregulated in the NAc of mice that are susceptible to chronic social stress, as well as in the NAc of depressed human. We further establish that ACF induction is both necessary and sufficient for susceptibility to stress-induced depressive-like behaviors. Using ChIP-seq, we demonstrate that altered ACF binding after chronic stress is strongly correlated with altered nucleosome positioning, in particular, around the transcriptional start sites of affected genes. These alterations in ACF binding and nucleosome repositioning are associated with repressed expression of a subset of genes in animals that are susceptible to chronic stress. Together, these findings establish that active ATP-dependent chromatin remodeling by the ACF complex is a key regulator in the repression of genes that mediate susceptibility to social stress, and provide novel candidate targets for improved therapeutics of depression and other stress-related disorders. c57bl/6 mice underwent chronic social defeat stress (CSDS), and social interaction test was used to separate animals into control, susceptible and resilient groups. Nucleus accumbens (NAc) tissue was collected 48 hours after the last defeat session, and then Acf1, SNF2H ChIP-seq or H3 MNase-seq were performed based on the control, susceptible, and resilient groups. Three sequencing replicates were performed on each group.

Dataset Information

Aberrant H3.3 dynamics in NAc promote vulnerability to depressive-like behavior

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure