PUBLICATIONS
-2022-
Nugues C., Helassa N. and Haynes L. 2022. Mitosis, Focus on Calcium. Frontiers in Physiology, 17(13):951979.
Prakash O., Held M., McCormick LF., Gupta N., Lian LY., Antonyuk S., Haynes LP., Thomas NL and Helassa N. 2022. CPVT-associated calmodulin variants N531 and A102V dysregulate Ca2+ signalling via different mechanisms. Journal of Cell Science, 135(2):jcs258796.
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-2021-
Helassa N. 2021. TSPAN-7 as a key regulator of glucose-stimulated Ca2+ influx and insulin secretion. Journal of Physiology, 599(6), 1733-1734.
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-2020-
Coates C., Kerruth S., Helassa N., & TÓ§rÓ§k K. 2020. Kinetic Mechanisms of Fast Glutamate Sensing by Fluorescent Protein Probes. Biophysical Journal, 118(1), 117-127.
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-2019-
Helassa N., Nugues C., Rajamanoharan D., Burgoyne RD., & Haynes LP. 2019. A centrosome-localized calcium signal is essential for mammalian cell mitosis. The FASEB Journal, 33(12), 14602-14610.
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Dvorzhak A., Helassa N., TÓ§rÓ§k K., Schmitz D., & Grantyn R. 2019. Single Synapse Indicators of Impaired Glutamate Clearance Derived from Fast iGluu Imaging of Cortical Afferents in the Striatum of Normal and Huntington (Q175) Mice. Journal of Neuroscience, 39(20), 3970-3982.
Burgoyne RD., Helassa N., McCue HV., & Haynes LP. 2019. Calcium Sensors in Neuronal Function and Dysfunction. Cold Spring Harbor Perspectives in Biology, 11(5).
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Durst CD., Wiegert JS., Helassa N., Kerruth S., Coates C., Schulze C., Geeves M., TÓ§rÓ§k K. & Oertner, T. G. 2019. High-speed imaging of glutamate release with genetically encoded sensors. Nature Protocols, 14(5), 1401-1424.
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-2018-
Helassa N., Durst CD., Coates C., Kerruth S., Arif U., Schulze C., Wiegert JS., Geeves M., Oertner TG. & TÓ§rÓ§k K. 2017. Ultrafast glutamate sensors resolve high-frequency release at Schaffer collateral synapses. Proceedings of the National Academy of Science of the United States of America, 115(21):5594-99.
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-2017-
Helassa N., Antonyuk SV., Lian LY., Haynes LP. & Burgoyne RD. 2017. Biophysical and functional characterization of hippocalcin mutants responsible for human dystonia. Human Molecular Genetics, 26(13):2426-35.
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- 2016 -
Helassa N., Podor B., Fine A. & TÓ§rÓ§k K. 2016. Design and mechanistic insight into ultrafast calcium indicators for monitoring intracellular calcium dynamics. Scientific Reports, 6:38276.
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- 2015 -
Helassa N., Zhang XH., Conte I., Scaringi J., Esposito E., Bradley J., Carter T ., Morad M., Ogden D. & TÓ§rÓ§k K. 2015. Fast-response calmodulin-based fluorescent indicators reveal rapid intracellular calcium dynamics. Scientific Reports, 5:15978.
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- 2014 -
Helassa N., Garnett JP., Khan F., Pickup JC., Hahn KM., MacNevin CJ., Tarran R. & Baines DL. 2014. A novel fluorescent biosensor for detecting changes in airway surface liquid glucose concentration. Biochemical Journal, 464(2):213-20.
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- 2013 -
Helassa N., Quiquampoix H. & Staunton S. 2013. Structure, biological activity and environmental fate of insecticidal Bt (Bacillus thuringiensis) Cry proteins of bacterial and genetically modified plant origin. In: Molecular Environmental Soil Science. p 49-78. Eds Xu J., Sparks DL, Springer, Dordrecht, Heidelberg, New York, London.
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​​- 2012 -
Helassa N., Vollmer W., Breukink E., Vernet T. & Zapun A. 2012. The membrane anchor of penicillin-binding protein PBP2a from Streptococcus pneumoniae influences peptidoglycan chain length. FEBS Journal, 279(19):2071-81.
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Zapun A., Noirclerc-Savoye M., Helassa N. & Vernet T. 2012. Peptidoglycan assembly machines: the biochemical evidence. Microbial Drug Resistance, 18(3):256-60.
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- 2011 -
Helassa N., M’Charek A., Quiquampoix H., Noinville S., Déjardin P., Frutos R. & Staunton S. 2011. Effects of physicochemical interactions and microbial activity in the persistence of Cry1Aa Bt (Bacillus thuringiensis) toxin in soil. Soil Biology & Biochemistry, 43(5):1089-97.
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Helassa N., Revault M., Quiquampoix H., Déjardin P., Staunton S and Noinville S. 2011. Adsorption on montmorillonite prevents oligomerization of Bt Cry1Aa toxin. Journal of Colloid and Interface Science, 356(2):718-25.
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- 2010 -
Helassa N., Noinville S., Déjardin P., Janot J.M., Quiquampoix H. & Staunton S. 2010. Interaction of Bt toxin with organo-mineral surfaces and consequences for its fate in the environment. In: Molecular Environmental Soil Science at the Interfaces in the Earth’s Critical Zone, p 187-189. Eds Xu J., Huang PM. Springer. Heidelberg, Dordrecht, London, New York.
Helassa N., Daudin, G., Noinville S., Janot JM., Déjardin P., Staunton S. & Quiquampoix H. 2010. FRAP reveals no mobility of Insecticidal Bacillus thuringiensis toxin adsorbed on montmorillonite. Philosophical Magazine, 90(17-18):2365-71.
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Janot J.M., Boissière M., Thami T., Tronel-Peyroz E., Helassa N., Noinville S., Revault M., Quiquampoix H., Staunton S. & Déjardin P. 2010. Adsorption of Bt toxin on mica and glass. Study by normal scanning confocal fluorescence. Biomacromolecules. 11(6):1661–6.
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- 2009 -
Helassa N., Quiquampoix H., Noinville S., Szponarski W. & Staunton S. 2009. Adsorption and desorption of monomeric Bt (Bacillus thuringiensis) Cry1Aa toxin on montmorillonite and kaolinite. Soil Biology & Biochemistry, 41(3):498-504.
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PRESENTATIONS AT INTERNATIONAL CONFERENCES
Helassa N., Dürst C., Coates C., Arif U., Schulze C., Wiegert S., Greeves M., Oertner T. & Török K. Novel iGluSnFR variants optimised for rapid glutamate imaging. 62nd Annual Meeting of the Biophysical Society, San Francisco, USA, 17-21 February 2018.
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Helassa N., Antonyuk SV., Lian LY., Haynes LP. & Burgoyne RD. Dystonia-associated hippocalcin mutants dysregulate cellular calcium influx. 62nd Annual Meeting of the Biophysical Society, San Francisco, USA, 17-21 February 2018.
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Coates C., Helassa N. & Török K. Diffusion-limited glutamate binding to GluBP is revealed by novel fluorescent probe. 62nd Annual Meeting of the Biophysical Society, San Francisco, USA, 17-21 February 2018.
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Dürst C., Wiegert JS., Schulze C., Helassa N., Török K. & Oertner T. Measuring glutamate transients at individual Schaffer collateral synapses. Society for Neuroscience, Washington DC, USA, 11-15 November 2017.
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Helassa N., Dürst C., Arif U., Schulze C., Oertner T. & Török K. Improved probes for investigating glutamate neurotransmission. Society for Neuroscience, San Diego, USA, 12-16 November 2016.
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Helassa N., Antonyuk SV., Lian LY., Haynes LP. & Burgoyne RD. Dystonia-causing mutations in hippocalcin show oligomerisation defect and translocation impairment. British Biophysical Society, Liverpool, UK, 6-8 July 2016.
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Helassa N., Podor B., Zhang X., Morad M., Fine A. & Török K. Development of Fast Genetically- Encoded Calcium Indicators for Monitoring Calcium Flux. Junior Scientist Workshop on Protein Engineering: Making and Using Tools for Neuroscience and Other Biological Problems, HHMI-Janelia Farm, Ashburn, USA, 13-18 March 2016.
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Helassa N., Podor B., Fine A. & Török K. Development of fast-response GCaMP6 calcium sensors for monitoring neuronal action potential. 60th Annual Meeting of the Biophysical Society, Los Angeles, USA, 27-02 March 2016.
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Helassa N., Podor B., Fine A. & Török K. Development of novel fast-response GCaMP6 sensors for monitoring neuronal action potential. Society for Neuroscience, Chicago, USA, 17-21 October 2015.
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Helassa N., Haynes L., Burgoyne R. & Török K. Novel stage-specific fluorescent indicators for mapping calcium signals during mitosis in mammalian cells. EMBO workshop: Cell cycle, Budapest, Hungary, 4-7 September 2015.
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Scaringi J., Helassa N., Török K. & Morad M. GCaMP3-Derived Genetically Encoded Probes as Rapid Intracellular Signals for Calcium Dynamics. 59th Annual Meeting of the Biophysical Society, Baltimore, USA, 7-11 February 2015.
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Helassa N., Esposito E., Conte I., Carter T., Bradley J., Ogden D., & Török K. Development of a new fast-response GCaMP3 family for monitoring calcium flux in vivo. Society for Neuroscience, Washington DC, USA, 15-19 November 2014.
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Helassa N., Esposito E., Carter T., Bradley J., Ogden D. & Török K. Ultrafast GCaMP for tracking calcium flux in vivo. Physiology 2014, London, UK, 30 June-2 July 2014.
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Helassa N., Esposito E., Carter T., Bradley J., Ogden D. & Török K. Ultrafast genetically encoded calcium indicators for visualizing calcium flux and action potentials. 58th Annual Meeting of the Biophysical Society, San Francisco, USA, 15-19 February 2014.
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Zapun A., Noirclerc-Savoye M., Breukink E., Helassa N. & Vernet T. Morphogenesis of the pneumococcus: finding the two activities of bifunctional PBPs. EMBO Workshop: Reconstructing the essential bacterial cell cycle machinery. Real Sitio de San Ildefonso (Segovia), Spain, 16-19 September 2012.
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Noirclerc-Savoye M., Helassa N., Rechenman M., Vernet T. & Zapun A. Membrane protein complexes of the pneumococcal cell wall assembly. Great Wall symposium, Lisboa, Portugal, 28-30 September 2011.
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Helassa N., Noinville S., Déjardin P., Quiquampoix H. & Staunton S. The mobility and persistence of the insecticidal Cry1Aa toxin, Bt (Bacillus thuringiensis) in soils. 19th World Congress of Soil Science, Brisbane, Australia, 1-6 August 2010.
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Staunton S., Quiquampoix H. & Helassa N. Interaction of Bt toxin with organo-mineral surfaces and consequences for its fate in the environment. ISMESS, Hangzhou, China, 10-14 October 2009.
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Helassa N., M’Charek A., Noinville S., Déjardin P., Quiquampoix H. & Staunton S. How do the interactions between soil organo-mineral surfaces and the insecticidal protein, Bt determine its persistence in the environment? ISEB, Hamburg, Germany, 14-18 September 2009.
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Masson S., Kern T., Le Gouellec A., Simorre J.P., Callow P., Vernet T., Gabel F., Helassa N. & Zapun A. The bacterial cell division enigmatic trio: DivIB, FtsL and DivIC - Functional and structural studies of the pneumococcal proteins. EMBO Workshop: Frontiers of Prokaryotic Cell Biology, Oxford, United Kingdom, 24–27 August 2009.
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Masson S., Kern T., Le Gouellec A., Simorre J.P., Callow P., Helassa N. & Vernet T. Bacterial cell division, the enigmatic trio : DivIB, FtsL, DivIC. Penicillin-recognizing enzymes: from enzyme kinetics to protein folding symposium, Liege, Belgium, 1-3 July 2009.
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Janot J.M., Thami T., Helassa N., Tronel-Peyroz E., Boissière M., Noinville S., Revault M., Quiquampoix H., Staunton S. & Déjardin P. Adsorption of Bt Toxin Monomer And Oligomers On Mica And Glass Studied by Scanning Confocal Fluorescence. 83rd ACS Colloid and Surface Science Symposium, New York, USA, 14 – 19 June 2009.
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20- Helassa N., Noinville S., Déjardin P., Janot J.M., Quiquampoix H. & Staunton S. Persistence of Bt Bacillus thuringiensis Cry1Aa toxin in various soils determined by physicochemical reactions. EGU, Vienne, Austria, 19-24 April 2009.
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Helassa N., Daudin G., Noinville S., Déjardin P., Janot J.M., Quiquampoix H. & Staunton S. Interactions of Bt Cry 1Aa toxin with soil and soil components : adsorption, extraction and persistence. ISMOM, Pucon, Chili, 24-29 November 2008.
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Helassa N., Quiquampoix H., Noinville S., Sauvage F.-X., Szponarski W. & Staunton S. Adsorption and desorption of monomeric Bt (Bacillus thuringiensis) Cry1Aa toxin on two reference minerals : montmorillonite and kaolinite. EUROSOIL, Vienne, Austria, 25–29 August 2008.
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Helassa N., M’Charek A., Daudin G., Noinville S., Déjardin P., Quiquampoix H. & Staunton S. Kinetics of microbial degradation and chemical fixation of Cry 1Aa Bt toxin in various soils. 41st Annual Meeting of the Society for Invertebrate Pathology and 9th International Conference on Bacillus thuringiensis, Warwick, United Kingdom, 5-7 August 2008.
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Janot J.M., Boissière M., Thami T., Tronel-Peyroz E., Helassa N., Noinville S., Revault M., Quiquampoix H., Staunton S. & Déjardin P. 2008. Adsorption of Bt toxin on mica and glass: Study by normal scanning confocal fluorescence. 82nd ACS Colloid and Surface Science Symposium, Raleigh, USA, 15-18 June 2008.
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Fall S., Herrera A., Helassa N., Bernillon D., Simonet P., Vogel T.M. & Navarro E. Prospecting for nickel resistant genes in soil metagenomes. 9th Symposium on Bacterial Genetics and Ecology (BAGECO), Wernigerode, Germany, 23-27 June 2007.
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Fall S., Herrera A., Helassa N., Bernillon D., Simonet P., Vogel, T.M. & Navarro E. Prospecting for nickel resistant determinants in a soil metagenome from New Caledonia. 11th International symposium on Microbial Ecology (ISME), Vienna, Austria, 20-25 August 2006.
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