{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T19:46:22Z","timestamp":1788291982682,"version":"build-2803163510"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T00:00:00Z","timestamp":1738800000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Lee Kong Chian MedTech Initiative, Singapore","award":["N-176-000-045-001"],"award-info":[{"award-number":["N-176-000-045-001"]}]},{"name":"Lee Kong Chian MedTech Initiative, Singapore","award":["E-551-00-0004-01"],"award-info":[{"award-number":["E-551-00-0004-01"]}]},{"name":"Pulsing Magnetic Field Therapy Research Fund","award":["N-176-000-045-001"],"award-info":[{"award-number":["N-176-000-045-001"]}]},{"name":"Pulsing Magnetic Field Therapy Research Fund","award":["E-551-00-0004-01"],"award-info":[{"award-number":["E-551-00-0004-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>The cryptochromes are flavoproteins that either individually or synergistically respond to light and magnetic field directionality as well as are implicated in circadian rhythm entrainment and development. Single brief exposures (10 min) to low energy (1.5 mT) pulsed electromagnetic fields (PEMFs) were previously shown to enhance myogenesis by stimulating transient receptor potential canonical 1 (TRPC1)-mediated Ca2+ entry, whereby downwardly directed fields produced greater myogenic enhancement than upwardly directed fields. Here, we show that growth in the dark results in myoblasts losing their sensitivity to both magnetic field exposure and directionality. By contrast, overexpressing or silencing cryptochrome circadian regulator 2 (CRY2) in myoblasts enhances or reduces PEMF responses, respectively, under conditions of ambient light. Reducing cellular flavin adenine dinucleotide (FAD) content by silencing riboflavin kinase (RFK) attenuated responsiveness to PEMFs and inhibited selectivity for magnetic field direction. The upregulation of TRPC1 and cell cycle regulatory proteins typically observed in response to PEMF exposure was instead attenuated by upwardly directed magnetic fields, growth in the darkness, magnetic shielding, or the silencing of CRY2 or RFK. A physical interaction between CRY2 and TRPC1 was detected using coimmunoprecipitation and immunofluorescence, revealing their co-translocation into the nucleus after PEMF exposure. These results implicate CRY2 in an identified TRPC1-dependent magnetotransduction myogenic cascade.<\/jats:p>","DOI":"10.3390\/cells14030231","type":"journal-article","created":{"date-parts":[[2025,2,6]],"date-time":"2025-02-06T04:47:31Z","timestamp":1738817251000},"page":"231","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Magnetically Stimulated Myogenesis Recruits a CRY2-TRPC1 Photosensitive Signaling Axis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5900-2033","authenticated-orcid":false,"given":"Jan Nikolas","family":"Iversen","sequence":"first","affiliation":[{"name":"Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"},{"name":"Institute of Health Technology and Innovation (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0798-3575","authenticated-orcid":false,"given":"Yee Kit","family":"Tai","sequence":"additional","affiliation":[{"name":"Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"},{"name":"Institute of Health Technology and Innovation (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"},{"name":"NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9942-239X","authenticated-orcid":false,"given":"Kwan Yu","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"},{"name":"Institute of Health Technology and Innovation (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0840-9922","authenticated-orcid":false,"given":"Craig Jun Kit","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"},{"name":"Institute of Health Technology and Innovation (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-2796-0994","authenticated-orcid":false,"given":"Hao Yang","family":"Lim","sequence":"additional","affiliation":[{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"},{"name":"Department of Biochemistry and Pharmacology, School of Biomedical Sciences, University of Melbourne, Melbourne, VIC 3010, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2514-1083","authenticated-orcid":false,"given":"Alfredo","family":"Franco-Obreg\u00f3n","sequence":"additional","affiliation":[{"name":"Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore"},{"name":"Institute of Health Technology and Innovation (iHealthtech), National University of Singapore, Singapore 117599, Singapore"},{"name":"Biolonic Currents Electromagnetic Pulsing Systems Laboratory (BICEPS), National University of Singapore, Singapore 117599, Singapore"},{"name":"NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore"},{"name":"Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore"},{"name":"Competence Center for Applied Biotechnology and Molecular Medicine, University of Z\u00fcrich, 8057 Z\u00fcrich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhang, L., and Malkemper, E.P. (2023). Cryptochromes in mammals: A magnetoreception misconception?. Front. Physiol., 14.","DOI":"10.3389\/fphys.2023.1250798"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Sherrard, R.M., Morellini, N., Jourdan, N., El-Esawi, M., Arthaut, L.D., Niessner, C., Rouyer, F., Klarsfeld, A., Doulazmi, M., and Witczak, J. (2018). Low-intensity electromagnetic fields induce human cryptochrome to modulate intracellular reactive oxygen species. PLoS Biol., 16.","DOI":"10.1371\/journal.pbio.2006229"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Margiotta, J.F., and Howard, M.J. (2020). Cryptochromes Mediate Intrinsic Photomechanical Transduction in Avian Iris and Somatic Striated Muscle. Front. Physiol., 11.","DOI":"10.3389\/fphys.2020.00128"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2118","DOI":"10.1016\/j.celrep.2018.01.077","article-title":"Cry2 Is Critical for Circadian Regulation of Myogenic Differentiation by Bclaf1-Mediated mRNA Stabilization of Cyclin D1 and Tmem176b","volume":"22","author":"Lowe","year":"2018","journal-title":"Cell Rep."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1257","DOI":"10.1007\/s43630-022-00216-0","article-title":"Multiple LEDT wavelengths modulate the Akt signaling pathways and attenuate pathological events in mdx dystrophic muscle cells","volume":"21","author":"Mizobuti","year":"2022","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.ceca.2016.12.009","article-title":"TRPC1, Orai1, and STIM1 in SOCE: Friends in tight spaces","volume":"63","author":"Ambudkar","year":"2017","journal-title":"Cell Calcium"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"571","DOI":"10.1007\/s00424-010-0847-8","article-title":"Canonical TRP channels and mechanotransduction: From physiology to disease states","volume":"460","author":"Patel","year":"2010","journal-title":"Pflugers Arch."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1016\/j.tibs.2024.05.004","article-title":"Re-evaluating TRP channel mechanosensitivity","volume":"49","author":"Cox","year":"2024","journal-title":"Trends Biochem. Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"12853","DOI":"10.1096\/fj.201900057R","article-title":"Ambient and supplemental magnetic fields promote myogenesis via a TRPC1-mitochondrial axis: Evidence of a magnetic mitohormetic mechanism","volume":"33","author":"Yap","year":"2019","journal-title":"FASEB J."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Bocchero, U., Falleroni, F., Mortal, S., Li, Y., Cojoc, D., Lamb, T., and Torre, V. (2020). Mechanosensitivity is an essential component of phototransduction in vertebrate rods. PLoS Biol., 18.","DOI":"10.1371\/journal.pbio.3000750"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Formoso, K., Susperreguy, S., Freichel, M., and Birnbaumer, L. (2020). RNA-seq analysis reveals TRPC genes to impact an unexpected number of metabolic and regulatory pathways. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-61177-x"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Wong, C.J.K., Tai, Y.K., Yap, J.L.Y., Fong, C.H.H., Loo, L.S.W., Kukumberg, M., Frohlich, J., Zhang, S., Li, J.Z., and Wang, J.W. (2022). Brief exposure to directionally-specific pulsed electromagnetic fields stimulates extracellular vesicle release and is antagonized by streptomycin: A potential regenerative medicine and food industry paradigm. Biomaterials, 287.","DOI":"10.1016\/j.biomaterials.2022.121658"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Kurth, F., Tai, Y.K., Parate, D., van Oostrum, M., Schmid, Y.R.F., Toh, S.J., Yap, J.L.Y., Wollscheid, B., Othman, A., and Dittrich, P.S. (2020). Cell-Derived Vesicles as TRPC1 Channel Delivery Systems for the Recovery of Cellular Respiratory and Proliferative Capacities. Adv. Biosyst., 4.","DOI":"10.1002\/adbi.202000146"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Iversen, J.N., Frohlich, J., Tai, Y.K., and Franco-Obregon, A. (2024). Synergistic Cellular Responses Conferred by Concurrent Optical and Magnetic Stimulation Are Attenuated by Simultaneous Exposure to Streptomycin: An Antibiotic Dilemma. Bioengineering, 11.","DOI":"10.20944\/preprints202406.0362.v1"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"C1344","DOI":"10.1152\/ajpcell.00056.2011","article-title":"Stretch-activated calcium channel protein TRPC1 is correlated with the different degrees of the dystrophic phenotype in mdx mice","volume":"301","author":"Matsumura","year":"2011","journal-title":"Am. J. Physiol. Cell Physiol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Crocetti, S., Beyer, C., Schade, G., Egli, M., Frohlich, J., and Franco-Obregon, A. (2013). Low intensity and frequency pulsed electromagnetic fields selectively impair breast cancer cell viability. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0072944"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Hastings, M.H., Maywood, E.S., and Brancaccio, M. (2019). The Mammalian Circadian Timing System and the Suprachiasmatic Nucleus as Its Pacemaker. Biology, 8.","DOI":"10.3390\/biology8010013"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1093\/jb\/mvh159","article-title":"Regulatory mechanisms and function of ERK MAP kinases","volume":"136","author":"Torii","year":"2004","journal-title":"J. Biochem."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Calloni, G., and Vabulas, R.M. (2022). The structural and functional roles of the flavin cofactor FAD in mammalian cryptochromes. Front. Mol. Biosci., 9.","DOI":"10.3389\/fmolb.2022.1081661"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.celrep.2017.03.041","article-title":"FAD Regulates CRYPTOCHROME Protein Stability and Circadian Clock in Mice","volume":"19","author":"Hirano","year":"2017","journal-title":"Cell Rep."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"645","DOI":"10.1016\/S0896-6273(01)00240-9","article-title":"TRPC1 and TRPC5 form a novel cation channel in mammalian brain","volume":"29","author":"Strubing","year":"2001","journal-title":"Neuron"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1109\/JSTQE.2016.2561201","article-title":"Proposed Mechanisms of Photobiomodulation or Low-Level Light Therapy","volume":"22","author":"Hamblin","year":"2016","journal-title":"IEEE J. Sel. Top. Quantum Electron."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Franco-Obregon, A., Tai, Y.K., Wu, K.Y., Iversen, J.N., and Wong, C.J.K. (2023). The Developmental Implications of Muscle-Targeted Magnetic Mitohormesis: A Human Health and Longevity Perspective. Bioengineering, 10.","DOI":"10.3390\/bioengineering10080956"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"45","DOI":"10.2741\/3230","article-title":"The integrative function of TRPC channels","volume":"14","author":"Kiselyov","year":"2009","journal-title":"Front. Biosci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1146\/annurev-neuro-062012-170412","article-title":"Transient receptor potential channels and mechanosensation","volume":"36","author":"Eijkelkamp","year":"2013","journal-title":"Annu. Rev. Neurosci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"939","DOI":"10.3390\/cells3040939","article-title":"Classical Transient Receptor Potential 1 (TRPC1): Channel or Channel Regulator?","volume":"3","author":"Dietrich","year":"2014","journal-title":"Cells"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"795","DOI":"10.1007\/978-3-319-05161-1_4","article-title":"Photosensitive TRPs","volume":"223","author":"Hardie","year":"2014","journal-title":"Handb. Exp. Pharmacol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1313","DOI":"10.1016\/0896-6273(89)90069-X","article-title":"Molecular characterization of the Drosophila trp locus: A putative integral membrane protein required for phototransduction","volume":"2","author":"Montell","year":"1989","journal-title":"Neuron"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/0896-6273(89)90117-7","article-title":"Proper function of the Drosophila trp gene product during pupal development is important for normal visual transduction in the adult","volume":"3","author":"Wong","year":"1989","journal-title":"Neuron"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1038\/224285a0","article-title":"Abnormal electroretinogram from a Drosophila mutant","volume":"224","author":"Cosens","year":"1969","journal-title":"Nature"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"9652","DOI":"10.1073\/pnas.92.21.9652","article-title":"TRPC1, a human homolog of a Drosophila store-operated channel","volume":"92","author":"Wes","year":"1995","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Contreras, E., Nobleman, A.P., Robinson, P.R., and Schmidt, T.M. (2021). Melanopsin phototransduction: Beyond canonical cascades. J. Exp. Biol., 224.","DOI":"10.1242\/jeb.226522"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1007\/s00441-021-03500-0","article-title":"Opsins outside the eye and the skin: A more complex scenario than originally thought for a classical light sensor","volume":"385","author":"Moraes","year":"2021","journal-title":"Cell Tissue Res."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Liebert, A., Capon, W., Pang, V., Vila, D., Bicknell, B., McLachlan, C., and Kiat, H. (2023). Photophysical Mechanisms of Photobiomodulation Therapy as Precision Medicine. Biomedicines, 11.","DOI":"10.3390\/biomedicines11020237"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Lin, C., and Todo, T. (2005). The cryptochromes. Genome Biol., 6.","DOI":"10.1186\/gb-2005-6-5-220"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1038\/366162a0","article-title":"HY4 gene of A. thaliana encodes a protein with characteristics of a blue-light photoreceptor","volume":"366","author":"Ahmad","year":"1993","journal-title":"Nature"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1464","DOI":"10.1104\/pp.103.024372","article-title":"Primary inhibition of hypocotyl growth and phototropism depend differently on phototropin-mediated increases in cytoplasmic calcium induced by blue light","volume":"133","author":"Folta","year":"2003","journal-title":"Plant Physiol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"614","DOI":"10.1111\/jipb.12813","article-title":"Cryptochrome-mediated hypocotyl phototropism was regulated antagonistically by gibberellic acid and sucrose in Arabidopsis","volume":"62","author":"Zhao","year":"2020","journal-title":"J. Integr. Plant Biol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1146\/annurev-arplant-042110-103759","article-title":"The cryptochromes: Blue light photoreceptors in plants and animals","volume":"62","author":"Chaves","year":"2011","journal-title":"Annu. Rev. Plant Biol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"684","DOI":"10.1016\/j.tplants.2011.09.002","article-title":"The action mechanisms of plant cryptochromes","volume":"16","author":"Liu","year":"2011","journal-title":"Trends Plant Sci."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Wiltschko, R., Niessner, C., and Wiltschko, W. (2021). The Magnetic Compass of Birds: The Role of Cryptochrome. Front. Physiol., 12.","DOI":"10.3389\/fphys.2021.667000"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1660","DOI":"10.1073\/pnas.1518622113","article-title":"Cryptochrome 2 mediates directional magnetoreception in cockroaches","volume":"113","author":"Bazalova","year":"2016","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1146\/annurev-biophys-032116-094545","article-title":"The Radical-Pair Mechanism of Magnetoreception","volume":"45","author":"Hore","year":"2016","journal-title":"Annu. Rev. Biophys."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Usselman, R.J., Chavarriaga, C., Castello, P.R., Procopio, M., Ritz, T., Dratz, E.A., Singel, D.J., and Martino, C.F. (2016). The Quantum Biology of Reactive Oxygen Species Partitioning Impacts Cellular Bioenergetics. Sci. Rep., 6.","DOI":"10.1038\/srep38543"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Cartes-Saavedra, B., Ghosh, A., and Hajnoczky, G. (2025). The roles of mitochondria in global and local intracellular calcium signalling. Nat. Rev. Mol. Cell Biol., 1\u201320.","DOI":"10.1038\/s41580-024-00820-1"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Usselman, R.J., Hill, I., Singel, D.J., and Martino, C.F. (2014). Spin biochemistry modulates reactive oxygen species (ROS) production by radio frequency magnetic fields. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0093065"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"3105","DOI":"10.1242\/dev.104851","article-title":"Circadian clock-mediated control of stem cell division and differentiation: Beyond night and day","volume":"141","author":"Brown","year":"2014","journal-title":"Development"}],"container-title":["Cells"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4409\/14\/3\/231\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:27:50Z","timestamp":1760027270000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4409\/14\/3\/231"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,6]]},"references-count":47,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["cells14030231"],"URL":"https:\/\/doi.org\/10.3390\/cells14030231","relation":{},"ISSN":["2073-4409"],"issn-type":[{"value":"2073-4409","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,6]]}}}