Maternal preparatory nesting elicits activity in the EW nucleus
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Peptidergic EW neurons are necessary for maternal preparatory nesting
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Progesterone alters peptidergic EW neuron firing and triggers preparatory nesting
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Peptidergic EW neurons project to and modulate many regions controlling nesting
Summary
Optimizing reproductive fitness in mammalians requires behavioral adaptations during pregnancy. Maternal preparatory nesting is an essential behavior for the survival of the upcoming litter. Brain-wide immediate early gene mapping in mice evoked by nesting sequences revealed that phases of nest construction strongly activate peptidergic neurons of the Edinger-Westphal nucleus in pregnant mice. Genetic ablation, bidirectional neuromodulation, and in vitro and in vivo activity recordings demonstrated that these neurons are essential to modulate arousal before sleep to promote nesting specifically. We show that these neurons enable the behavioral effects of progesterone on preparatory nesting by modulating a broad network of downstream targets. Our study deciphers the role of midbrain CART+ neurons in behavioral adaptations during pregnancy vital for reproductive fitness.
Present address: Kavli Institute for Fundamental Neuroscience, Department of Anatomy, UCSF, San Francisco, and Lawrence Berkeley National Laboratory, Berkeley, CA, USA