Collaborative Research: Targeted neurosteroidogenesis and complex memory function

Hormones travel through the blood and profoundly affect tissues far from their source. Neurons communicate with electrical signals and the release of neurotransmitters across the microscopic space of a synapse. We have recently documented a combination of these two signaling systems, one example of which is estrogen synthesis at the synapse (SES).

However, we know little about how electrical and hormonal signaling interact at the synapse, or how this SES may affect complex behaviors like memory function. Neither do we know if learning affects SES. We will use the zebra finch, a species with abundant SES to understand how synaptic steroid synthesis interacts with membrane electrical activity and neurotransmitter release.

Then, we will ask how SES modulates learning, storage and recall of newly learned spatial information. Lastly, we will probe changes in the genome associated with learning, memory, and SES. The investigators on this project are all committed to undergraduate education and extend research opportunities to students and area high school teachers, thereby increasing outreach at local institutions.

The PI will host a streaming video show highlighting the interactions between healthy food preparation and hormonal change. Finally, we will provide content on the physiological and vocal changes to LBGT+ choruses and choirs on the effects of hormone therapy on vocal performance. These outreach activities are designed to exploit the researchers’ scholarly, outreach, and public engagement to increase the awareness of scientific research to a diverse set of citizens.

Synaptocrine signaling, evidenced by steroid synthesis at the synapse may be a signaling system that combines paracrine and electrical signaling. The abundant synaptic aromatase in the finch brain makes it an invaluable model in understanding the interplay between electrical activity and steroid provision. Further, the accessibility of the avian hippocampus (HP), the plentiful synaptic aromatase therein, and its established role in spatial memory, allow for an unparalleled opportunity to understand the role of synaptocrine aromatization in memory formation and performance.

We propose to use biochemical, behavioral, and genomic techniques to understand how: ionic flux affects hormone synthesis and neurotransmitter release at the synapse, how aromatization in the HP affects components of memory function, and how changes in the hippocampal transcriptome are altered by aromatization and learning. This proposal combines the skills of researchers at two predominantly undergraduate institutions, all of whom are committed to academic and public education.

The PIs will welcome high school teachers and undergraduates into their laboratories for summer internships and will design and implement a new course in Neuroanatomy for undergraduates in Neuroscience. Public outreach will consist of a streaming cooking show that discusses the endocrinology and physiological consequences of healthy food preparation.

Finally, the PI and a colleague in Music will design and provide content to choral performers in the LBGT+ community on respiratory and vocal changes during chronic hormone-therapy. Taken together these outreach activities will benefit a wide array of the public across ages, genders, ethnicities, and socioeconomic groups.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.