Grant: Operating Grant

The human brain is comprised on 100 billion neurons that are organized into either distinct layers or defined clusters ("nuclei"). Over the past decade, the developmental neuroscience community has been focused on dissecting how neurons become organized into layers. Comparatively, little is known about how neurons become organized into nuclei. One reason for this disparity is the assumption that nuclei lack a precise organization. This is mistaken - on the contrary, most brain nuclei exhibit an impressive suborganization. One brain region that organizes its neurons into nuclei is the hypothalamus. The hypothalamus processes cues from our surrounding and internal environments to control physiologies that ensure our survival, such as eating when we are hungry. The hypothalamus also is an advantageous brain region to begin to understand how neurons become organized into nuclei because its nuclei express unique markers that label distinct subdomains. Thus, we can track the birth and migration of these markers as a way to understand how nuclei are formed. Here, we will use our unique collection of molecular markers to study how neurons that reside in one nucleus - the ventromedial hypothalamic nucleus - are born and move to their final position. It is important that we start to understand how the brain gets its nuclei. Not only because, broadly speaking, 66 billion of the brain's 100 billion neurons are organized into clusters, but also because neuroendocrine disorders are becoming more common in the general population and these diseases are probably caused on some level by a disruption of nuclei organization. Before we can adequately design therapies to treat these disorders, we first need to understand how nuclear brain structures develop.