**ABSTRACT NOT FOR CITATION WITHOUT AUTHOR PERMISSION. The title, authors, and abstract for this completion report are provided below.  For a copy of the full completion report, please contact the author via e-mail at liweim@msu.edu or via telephone at 517-432-6705. Questions? Contact the GLFC via email at frp@glfc.org or via telephone at 734-662-3209.**

 

STRUCTURE AND FUNCTION OF SEA LAMPREY PHEROMONE COMPONENTS

 

 

Ke Li1, Cory O Brant1, Mar Huertas1, Weiming Li1

 

1 Department of Fisheries and Wildlife, Michigan State University, Giltner Hall 142, 293 Farm Lane,  East Lansing, MI 48824.

 

 

December 2014

 

ABSTRACT:

 

Migratory and male mating pheromones are indispensible for sea lamprey reproduction, and thus are ideal for use to the advantage of sea lamprey control. The main component of the male pheromone, 3kPZS (7α, 12α, 24-trihydroxy-5α-cholan-3-one-24-sulfate), has been shown unequivocally to attract ovulatory females to nests. To date, however, no other putative pheromones isolated from either adult male or larval sea lampreys have been shown to influence the distribution or behavior of adult sea lampreys in streams. In this study we elucidated the structures and functions of additional pheromone components. Using an activity-directed fractionation strategy, we extracted washings from spermiating male and larval sea lampreys separately with SPE (solid phase extraction), fractionated the extracts with TLC (Thin Layer Chromatography) and HPLC (High Performance Liquid Chromatography), and tested the fractions for their olfactory potency by EOG (Electro-Olfactogram) recording. We elucidated the molecular structures of active components by either NMR (Nuclear Magnetic Resonance) or crystallographic X-ray diffraction, and further confirmed the structures with spectra of synthesized compounds. The pheromone functions of isolated and synthesized compounds were tested using in-stream behavior assays that integrate Passive Integrated Transponder (PIT) technology and visual observation. Using these approaches, we identified nine compounds, confirmed that three compounds have putative migratory functions and one compound has putative mating pheromone functions. We expect that further studies of these compounds may lead to novel or additional strategies for integrated sea lamprey management.