Grant: Discovery Grants Program - Individual

The long-term objective is to understand how the brain and pituitary gland release hormones that control the ovaries and testes in fish. Environmental signals such as light and temperature can regulate reproduction by changing the levels and activities of key genes and hormones. Moreover, many environmental pollutants can disrupt these fine-tuned processes such that fertility is reduced, or reproduction is totally inhibited. We know this because we have used methods that measure thousands of genes and hundreds of proteins in the brain following hormone treatments or experiments where we alter the environmental conditions. In the last few years my laboratory made two compelling recent discoveries in the goldfish model organism that provide the foundation for this proposal. We will specifically study the role of a major neurotransmitter called dopamine, and a novel neuropeptide called secretoneurin. They are key players in a complex pathway leading to the release of luteinizing hormone from the pituitary gland. Luteinizing hormone is the essential factor controlling egg production or sperm production, and sex steroid production in vertebrate animals, be they fish, frogs or humans. Moreover, our previous research indicates that the functions of dopamine to inhibit and secretoneurin to stimulate LH appear to be highly similar in fish and mammals. Therefore, the knowledge gained for one model species may help us understand reproduction control mechanisms in other species. On a more practical scale, establishing the factors that regulate LH release may have important applications for controlled reproduction in fish aquaculture. Also very important is that young scientists will conduct this research and get training in state-of-the art techniques. These include methods such as DNA microarrays (the so-called ""DNA chip"") and proteomics (a high powered method to measure hundreds of proteins at one time). These graduate and undergraduate students will be mentored on career development, will publish their results in scientific journals. They will be highly sought after by academia, industrial research and development organizations, or government research departments.