title: Light-dependent magnetic compass orientation in amphibians and insects: candidate receptors and candidate molecular mechanisms.
abstract: Magnetic compass orientation by amphibians, and some insects, is mediated by a light-dependent magnetoreception mechanism. Cryptochrome photopigments, best known for their role in circadian rhythms, are proposed to mediate such responses. In this paper, we explore light-dependent properties of magnetic sensing at three levels: (i) behavioural (wavelength-dependent effects of light on magnetic compass orientation), (ii) physiological (photoreceptors/photopigment systems with properties suggesting a role in magnetoreception), and (iii) molecular (cryptochrome-based and non-cryptochrome-based signalling pathways that are compatible with behavioural responses). Our goal is to identify photoreceptors and signalling pathways that are likely to play a specialized role in magnetoreception in order to definitively answer the question of whether the effects of light on magnetic compass orientation are mediated by a light-dependent magnetoreception mechanism, or instead are due to input from a non-light-dependent (e.g. magnetite-based) magnetoreception mechanism that secondarily interacts with other light-dependent processes.
authors.affiliation: Department of Biological Sciences, Virginia Polytechnic Institute and State University, Derring Hall, Blacksburg, VA 24061, USA. jphillip@vt.edu
authors.forename: John B
authors.initials: JB
authors.lastname: Phillips
authors.forename: Paulo E
authors.initials: PE
authors.lastname: Jorge
authors.forename: Rachel
authors.initials: R
authors.lastname: Muheim
mesh_terms: D000663:Amphibians / Q000502:physiology*; D000818:Animals; D056931:Cryptochromes / Q000378:metabolism*; D004574:Electromagnetic Fields; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007313:Insecta / Q000502:physiology*; D008027:Light; D009949:Orientation / Q000502:physiology* / Q000528:radiation effects*; D010465:Perception / Q000502:physiology / Q000528:radiation effects
chemical_list: D056931:Cryptochromes