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Wood, D. J.

Publications and source records attributed to Wood, D. J..

3 recordsLinked to original sources

NPAS4 supports drug-cue associations and relapse-like behavior through regulation of the cell type-specific activation balance in the nucleus accumbens

Use of addictive substances creates powerful drug-cue associations that often trigger relapse. Drug seeking is gated in the nucleus accumbens (NAc) by competing activation of D1 dopamine receptor-expressing medium spiny neurons (D1-MSNs) that promote, and D2 dopamine receptor-expressing neurons (D2-MSNs) that oppose, drug seeking. We show here that the ensemble of neurons in the NAc that induce the neuronal activity-regulated transcription factor, Neuronal PAS Domain Protein 4 (NPAS4), is required for cocaine-context associations. In addition, NPAS4 functions within NAc D2-MSNs to govern the activation balance of NAc D1-MSNs and D2-MSNs necessary for drug-context memories and cue-induced cocaine, but not sucrose, seeking. NPAS4 regulates drug-cue associations and preponderant D1-MSN activation by influencing a program of gene expression that blocks cocaine-induced potentiation of prefrontal cortical excitatory drive onto D2-MSNs. Together our findings reveal that NPAS4 is a key player governing NAc MSN cell-type activation balance and promoting drug-cue associations and relapse vulnerability.

neuroscience↗

Early life stress-induced vulnerability to postpartum mental disturbance: prolonged dysregulation of the HPA axis and behavior

Stress during childhood and adolescence increases the risk for postpartum depression (PPD). Patients with depression who have experienced adverse life events tend to be treatment refractory. However, the mechanism by which stress during childhood and adolescence are involved in the pathophysiology of PPD remains unclear. We investigated the longitudinal effects of adolescent stress on the hypothalamic-pituitary-adrenal (HPA) axis and behaviors in the postpartum period through mouse and human studies. We observed that adolescent social isolation caused an aberrantly sustained elevation of glucocorticoids via dysregulation of the HPA axis, leading to long-lasting postpartum behavioral changes in female mice. The postpartum behavioral changes elicited by this adolescent stress were not ameliorated by the medicines currently used for PPD treatment. However, a post-delivery treatment with a glucocorticoid receptor antagonist effectively ameliorated the behavioral changes in mice. We also demonstrated a significant impact of stress during childhood and adolescence on the HPA axis dysregulation and PPD in women. We provide experimental evidence that suggests a mechanism-driven therapeutic strategy (repurposing a GR antagonist) for at least some cases of treatment refractory PPD.

molecular biology↗

Discriminative SKP2 interactions with CDK-cyclin complexes support a cyclin A-specific role in p27KIP1 degradation

The SCFSKP2 ubiquitin ligase relieves G1 checkpoint control of CDK-cyclin complexes by promoting p27KIP1 degradation. We describe reconstitution of stable complexes containing SKP1-SKP2 and CDK1-cyclin B or CDK2-cyclin A/E, mediated by the CDK regulatory subunit CKS1. We further show that a direct interaction between a SKP2 N-terminal motif and cyclin A can stabilize SKP1-SKP2-CDK2-cyclin A complexes in the absence of CKS1. We identify the SKP2 binding site on cyclin A and demonstrate the site is not present in cyclin B or cyclin E. This site is distinct from but overlapping with features that mediate binding of p27KIP1 and other G1 cyclin regulators to cyclin A. We propose that the capacity of SKP2 to engage with CDK2-cyclin A by more than one structural mechanism provides a way to fine tune the degradation of p27KIP1 and distinguishes cyclin A from other G1 cyclins to ensure orderly cell cycle progression.

biochemistry↗