Femtosecond fiber laser technology for the study of DNA repair and chromatin dynamics

Irradiation of the cell nucleus with pulsed infrared femtosecond lasers is a powerful method to induce DNA damage at high spatial resolution and minimum collateral damage. DNA lesions are triggered by multiphoton absorption which is restricted to the objective focus and is thus precisely confined in three dimensions. The type of DNA damage induced strongly depends on the pulse parameters, in particular the wavelength. It is possible to engineer pulses that preferentially induce DNA strand breaks as compared e.g. UV-photoproducts. We aim at understanding the mechanisms underlying this specificity and exploit this knowledge for establishing nonlinear excitation by femtosecond pulses as a spatially precise, flexible and validated tool to manipulate nuclear DNA in living cells. We also apply this technology to study how the dynamics of chromatin is affected by DNA damage. This project is performed in the frame of the Center for Applied Photonics at the University of Konstanz.


  • Fischer JM, Popp O, Gebhard D, Veith S, Fischbach A, Beneke S, Leitenstorfer A, Bergemann J, Scheffner M, Ferrando-May E, Mangerich A, Bürkle A. Poly(ADP-ribose)-mediated interplay of XPA and PARP1 leads to reciprocal regulation of protein function. FEBS J. 281:3625-41 (2014).
  • Kassner I, Andersson A, Fey M, Tomas M, Ferrando-May E, Hottiger MO.
  • SET7/9-dependent methylation of ARTD1 at K508 stimulates poly-ADP-ribose formation after oxidative stress. Open Biol. 3:120173 (2013)
  • Dantas TJ, Daly OM, Conroy PC, Tomas M, Wang Y, Lalor P, Dockery P, Ferrando-May E, Morrison CG. Calcium-binding capacity of centrin2 is required for linear POC5 assembly but not for nucleotide excision repair. PLOS One 8: e68487 (2013).
  • Ferrando-May E, Tomas M, Blumhardt P, Stöckl M, Fuchs M, Leitenstorfer A. Highlighting the DNA damage response with ultrashort laser pulses in the near infrared and kinetic modeling. Front Genet. 4:135 (2013).
  • Tomas M, Blumhardt P, Deutzmann A, Schwarz T, Kromm D, Leitenstorfer A, Ferrando-May E. Imaging of the DNA damage-induced dynamics of nuclear proteins via nonlinear photoperturbation. J Biophotonics 6: 645-55 (2013)
  • Clement FC, Kaczmarek N, Mathieu N, Tomas M, Leitenstorfer A, Ferrando-May E, Naegeli H.
  • Dissection of the xeroderma pigmentosum group C protein function by site-directed mutagenesis. Antioxid Redox Signal. 14:2479-90 (2011)
  • Träutlein D, Deibler M, Leitenstorfer A, Ferrando-May E. Specific local induction of DNA strand breaks by infrared multi-photon absorption. Nucleic Acids Res. 38:e14 (2010)
  • Camenisch U, Träutlein D, Clement FC, Fei J, Leitenstorfer A, Ferrando-May E, Naegeli H. Two-stage dynamic DNA quality check by xeroderma pigmentosum group C protein. EMBO J. 28: 2387-99 (2009)
  • Träutlein D, Adler F, Moutzouris K, Jeromin A, Leitenstorfer A, Ferrando-May E.Highly versatile confocal microscopy system based on a tunable femtosecond Er:fiber source. J Biophotonics. 1: 53-61 (2008)


  • Federal Ministry of Education and Research (BMBF)
  • Excellence Initiative by the German State and Federal Governments
  • Ministry of Science, Research and the Arts of the State of Baden-Württemberg
  • Center for Applied Photonics (CAP, University of Konstanz)
  • Internationale Bodenseehochschule (IBH)
  • International Research Training Group IRTG1331
  • German Research Foundation(DFG)