Kinetic and photonic techniques to study chemotactic signaling in sea urchin sperm

Hamzeh, Hussein; Alvarez, Luis; Strünker, Timo; Kierzek, Michelina; Brenner, Chirstoph; Deal, Parker E; Miller, Evan W; Seifert, Reinhard; Kaupp, U Benjamin

Abstract

Sperm from sea urchins are attracted by chemical cues released by the egg-a mechanism called chemotaxis. We describe here the signaling pathway and molecular components endowing sperm with single-molecule sensitivity. Chemotactic signaling and behavioral responses occur on a timescale of a few milliseconds to seconds. We describe the techniques and chemical tools used to resolve the signaling events in time. The techniques include rapid-mixing devices, rapid stroboscopic microscopy, and photolysis of caged second messengers and chemoattractants.