Energy Expenditure Homeostasis Requires ErbB4, an Obesity Risk Gene, in the Paraventricular Nucleus.

Obesity affects more than a third adult population in the United States; the prevalence is even higher in patients with major depression disorders. GWAS studies identify the receptor tyrosine kinase ErbB4 as a risk gene for obesity and for major depression disorders. We found that ErbB4 was enriched in the paraventricular nucleus of the hypothalamus (PVH).

Ultrastructural view of astrocyte arborization, astrocyte-astrocyte and astrocyte-synapse contacts, intracellular vesicle-like structures, and mitochondrial network.

The complexity of astrocyte morphology and syncytial coupling through gap junctions are crucial for astrocyte function in the brain. However, the ultrastructural details of astrocyte arborization and interactions between neighboring astrocytes remain unknown. While a prevailing view is that synapses selectively contact peripheral astrocyte processes, the precise spatial-location selectivity of synapses abutting astrocytes is unresolved.

Neuregulin 1 and ErbB4 Kinase Actively Regulate Sharp Wave Ripples in the Hippocampus.

Sharp wave ripples (SW-Rs) in the hippocampus are synchronized bursts of hippocampal pyramidal neurons (PyNs), critical for spatial working memory. However, the molecular underpinnings of SW-Rs remain poorly understood. We show that SW-Rs in hippocampal slices from both male and female mice were suppressed by neuregulin 1 (NRG1), an epidermal growth factor whose expression is enhanced by neuronal activity.