title: A novel biosensor to study cAMP dynamics in cilia and flagella.
abstract: The cellular messenger cAMP regulates multiple cellular functions, including signaling in cilia and flagella. The cAMP dynamics in these subcellular compartments are ill-defined. We introduce a novel FRET-based cAMP biosensor with nanomolar sensitivity that is out of reach for other sensors. To measure cAMP dynamics in the sperm flagellum, we generated transgenic mice and reveal that the hitherto methods determining total cAMP levels do not reflect changes in free cAMP levels. Moreover, cAMP dynamics in the midpiece and principal piece of the flagellum are distinctively different. The sole cAMP source in the flagellum is the soluble adenylate cyclase (SACY). Although bicarbonate-dependent SACY activity requires Ca(2+), basal SACY activity is suppressed by Ca(2+). Finally, we also applied the sensor to primary cilia. Our new cAMP biosensor features unique characteristics that allow gaining new insights into cAMP signaling and unravel the molecular mechanisms underlying ciliary function in vitro and in vivo.
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Shatanik
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Jansen
authors.affiliation: Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Jan F
authors.initials: JF
authors.lastname: Jikeli
authors.affiliation: Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Hussein
authors.initials: H
authors.lastname: Hamzeh
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Luis
authors.initials: L
authors.lastname: Alvarez
authors.affiliation: Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Marco
authors.initials: M
authors.lastname: Dombrowski
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Balbach
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.|Centrum für Reproduktionsmedizin und Andrologie, Universitätsklinikum Münster, Münster, Germany.
authors.forename: Timo
authors.initials: T
authors.lastname: Strünker
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Seifert
authors.affiliation: Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: U Benjamin
authors.initials: UB
authors.lastname: Kaupp
authors.affiliation: Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research, Bonn, Germany.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Wachten
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002460:Cell Line; D002923:Cilia / Q000737:chemistry*; D000242:Cyclic AMP / Q000032:analysis*; D005407:Flagella / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D008297:Male; D008822:Mice, Transgenic; D012680:Sensitivity and Specificity; D013094:Spermatozoa / Q000737:chemistry
chemical_list: D000242:Cyclic AMP
keywords: FRET; cAMP; cell biology; ciliary; flagella; mouse; sperm