title: Cryptochromes and Hormone Signal Transduction under Near-Zero Magnetic Fields: New Clues to Magnetic Field Effects in a Rice Planthopper.
abstract: Although there are considerable reports of magnetic field effects (MFE) on organisms, very little is known so far about the MFE-related signal transduction pathways. Here we establish a manipulative near-zero magnetic field (NZMF) to investigate the potential signal transduction pathways involved in MFE. We show that exposure of migratory white-backed planthopper, Sogatella furcifera, to the NZMF results in delayed egg and nymphal development, increased frequency of brachypterous females, and reduced longevity of macropterous female adults. To understand the changes in gene expression underlying these phenotypes, we examined the temporal patterns of gene expression of (i) CRY1 and CRY2 as putative magnetosensors, (ii) JHAMT, FAMeT and JHEH in the juvenile hormone pathway, (iii) CYP307A1 in the ecdysone pathway, and (iv) reproduction-related Vitellogenin (Vg). The significantly altered gene expression of CRY1 and CRY2 under the NZMF suggest their developmental stage-specific patterns and potential upstream location in magnetic response. Gene expression patterns of JHAMT, JHEH and CYP307A1 were consistent with the NZMF-triggered delay in nymphal development, higher proportion of brachypterous female adults, and the shortened longevity of macropterous female adults, which show feasible links between hormone signal transduction and phenotypic MFE. By conducting manipulative NZMF experiments, our study suggests an important role of the geomagnetic field (GMF) in modulating development and physiology of insects, provides new insights into the complexity of MFE-magnetosensitivity interactions, and represents an initial but crucial step forward in understanding the molecular basis of cryptochromes and hormone signal transduction involved in MFE.
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Gui-Jun
authors.initials: GJ
authors.lastname: Wan
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Wen-Jing
authors.initials: WJ
authors.lastname: Wang
authors.affiliation: Beijing Key Laboratory of Bioelectromagetics, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Xu
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Quan-Feng
authors.initials: QF
authors.lastname: Yang
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Ming-Jiang
authors.initials: MJ
authors.lastname: Dai
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Feng-Jiao
authors.initials: FJ
authors.lastname: Zhang
authors.affiliation: Department of Entomology, Texas A&M University, College Station, TX, United States of America.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Sword
authors.affiliation: Beijing Key Laboratory of Bioelectromagetics, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Pan
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing, Jiangsu, China.
authors.forename: Fa-Jun
authors.initials: FJ
authors.lastname: Chen
mesh_terms: D000818:Animals; D056931:Cryptochromes / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression / Q000235:genetics; D017344:Genes, Insect / Q000235:genetics; D006430:Hemiptera / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D007605:Juvenile Hormones / Q000235:genetics / Q000378:metabolism*; D060526:Magnetic Fields; D008297:Male; D009758:Nymph / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D012275:Oryza; D012098:Reproduction / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*
chemical_list: D056931:Cryptochromes; D007605:Juvenile Hormones