Secretagogin expression in the vertebrate brainstem with focus on the noradrenergic system and implications for Alzheimer's disease.

Calcium-binding proteins are widely used to distinguish neuronal subsets in the brain. This study focuses on secretagogin, an EF-hand calcium sensor, to identify distinct neuronal populations in the brainstem of several vertebrate species. By using neural tube whole mounts of mouse embryos, we show that secretagogin is already expressed during the early ontogeny of brainstem noradrenaline cells.