Marten Vos, affiliated with École Polytechnique, Institut Polytechnique de Paris, has contributed a Perspectives piece within the same journal issue, elucidating the fundamental mechanisms of DNA repair observed in various non-mammalian organisms through the action of a protein called photolyase. The Perspectives piece further delves into the methodologies devised by the two independent research teams, featured in the same journal, which offer an intricate step-by-step depiction of how this repair process unfolds.
Previous studies have established that numerous animals, predominantly non-mammalian, have evolved a mechanism for repairing DNA damaged by ultraviolet (UV) radiation. This repair process involves a protein called photolyase, which isolates damaged DNA and utilizes the energy associated with photons to execute necessary repairs. Although the overarching concept of this repair process has been comprehended, the specific steps involved have remained elusive. In these latest studies, both research teams have innovatively crafted methodologies to capture the dynamic action moment by moment—a technique reminiscent of stop-motion animation commonly employed in the creation of movies.
Initiating from the understanding that UV-induced damage to DNA often leads to the disruption of base pairs, crucial for holding the two strands together, both research procedures share a common starting point. This UV-induced damage results in the separation of base pairs, leading adjacent pairs to bind with other broken strands. Consequently, this interlocking prevents the natural self-repair process of DNA.
In the initial study, a comprehensive international team employed time-resolved crystallography experiments to meticulously capture and observe the unfolding action of the repair mechanism. In the second study, another expansive international team of researchers opted for a multifaceted approach, combining time-resolved crystallography with computational analyses. This dual strategy allowed them to thoroughly document and comprehend the intricate details of the repair process.
In a coordinated effort, both research teams employed a sophisticated approach to document the intricate process of photolyase in action. By directing a laser at the photolyase during its repair activity, followed by the emission of X-ray pulses, the teams meticulously captured each step of the repair mechanism. Their investigations unveiled a remarkable sequence: a segment of the photolyase assumed a V shape, adept at capturing a photon and harnessing its energy.
This acquired energy facilitated the transformation of the V shape, flipping it upside down, and subsequently transferring an electron to a damaged DNA strand. This electron transfer induced the cleavage of the undesired bond within the DNA strand. The subsequent release of an electron restored the photolyase to its initial upright V position. In this restored state, the photolyase played a crucial role in facilitating the reformation of a new bond between the previously separated DNA strands by rejoining the base pairs. This detailed revelation of the repair process sheds light on the intricate molecular dance orchestrated by photolyase in its mission to rectify damaged DNA.
Resources
- ONLINE NEWS Yirka, B. & Phys.org. (2023, December 1). Two methods for demonstrating how photolyase isolates use light to repair damaged DNA. Phys.org. [Phys.org]
- JOURNAL Christou, N., Apostolopoulou, V., Melo, D. V. M., Ruppert, M., Fadini, A., Henkel, A., Sprenger, J., Oberthüer, D., Günther, S., Pateras, A., Mashhour, A. R., Yefanov, O., Galchenkova, M., Reinke, P., Kremling, V., Scheer, T. E. S., Lange, E., Middendorf, P., Schubert, R., . . . Lane, T. J. (2023). Time-resolved crystallography captures light-driven DNA repair. Science, 382(6674), 1015–1020. [Science]
- JOURNAL Maestre-Reyna, M., Wang, P., Nango, E., Hosokawa, Y., Saft, M., Furrer, A., Yang, C., Putu, E. P. G. N., Wu, W., Emmerich, H., Caramello, N., Franz-Badur, S., Yang, C., Engilberge, S., Wranik, M., Glover, H., Weinert, T., Wu, H., Lee, C. C., . . . Tsai, M. (2023). Visualizing the DNA repair process by a photolyase at atomic resolution. Science, 382(6674). [Science]
- JOURNAL Vos, M. H. (2023). Filming DNA repair at the atomic level. Science, 382(6674), 996–997. [Science]
Cite this page:
APA 7: TWs Editor. (2023, December 2). The Repair of Damaged DNA by Photolyase Isolates Using Light: Two Methods to Demonstrate It. PerEXP Teamworks. [News Link]
