ASTMH 2016, Ethan Degner: “There and back again: a mosquito sperm’s journey from insemination to fertilization”

In collaboration with ASTMH, Image Audiovisuals, and session presenters, MESA brings you this webcast from the 65th ASTMH annual meeting in Atlanta, November 2016.

Title: “There and back again: a mosquito sperm’s journey from insemination to fertilization”

Speaker: Ethan Degner, Cornell University, USA

Session information: Scientific Session 130: “Mosquitoes: Biochemistry and Molecular Biology”

Wednesday, 16 November, 10:15am – 12:00pm, Marriott – Room A706 / A707

Abstract:

Interfering with mosquito reproduction to control vector populations holds significant promise. Most investigative effort to develop novel control targets has focused on females, yet male contributions to reproduction are often overlooked. In particular, sperm biology and sperm’s movement through the female reproductive tract are poorly understood, but studying sperm may provide various opportunities to interrupt reproduction. During insemination, sperm are deposited in a semen-receiving organ, where they display hyperactivated motility. They quickly localize to ducts leading to long-term storage organs called spermathecae. Within minutes, they travel up these ducts and are maintained by the female for her entire life. Ultimately, they are carefully released for fertilization as eggs are laid. Completion of this journey requires the precise coordination of motility, interactions with the ejaculate, nourishment by the female, and possibly modifications to sperm that make them fertilization competent. These processes have been superficially examined microscopically, but very little is known about how sperm function on the molecular level. We discuss what is known of mosquito sperm’s path through the female, highlighting areas for future exploration and discussing possible molecular targets that could be exploited by vector control strategies. We also provide unprecedented footage of mosquito sperm motility inside the female reproductive tract that will aid our understanding of how sperm function in vivo.