tailieunhanh - Báo cáo y học: "Positioning Effects of KillerRed inside of Cells correlate with DNA Strand Breaks after Activation with Visible Light"

Tuyển tập các báo cáo nghiên cứu khoa học ngành y học tạp chí Medical Sciences dành cho các bạn sinh viên ngành y tham khảo đề tài: Positioning Effects of KillerRed inside of Cells correlate with DNA Strand Breaks after Activation with Visible Light. | Int. J. Med. Sci. 2011 8 97 Research Paper International Journal of Medical Sciences 2011 8 2 97-105 Ivyspring International Publisher. All rights reserved. Positioning Effects of KillerRed inside of Cells correlate with DNA Strand Breaks after Activation with Visible Light Waldemar Waldeck1 Gabriele Mueller1 Manfred Wiessler2 Katalin Tóth1 and Klaus Braun2 H 1. German Cancer Research Center Dept. of Biophysics of Macromolecules INF 580 D-69120 Heidelberg Germany 2. German Cancer Research Center Dept. of Medical Physics in Radiology INF 280 D-69120 Heidelberg Germany H Corresponding author Dr. Klaus Braun German Cancer Research Center DKFZ Dept. of Medical Physics in Radiology Im Neuenheimer Feld 280 D-69120 Heidelberg Germany. Phone 49 6221-42 2495 Fax 49 6221-42 3326 e-mail . de Received Accepted Published Abstract Fluorescent proteins FPs are established tools for new applications not-restricted to the cell biological research. They could also be ideal in surgery enhancing the precision to differentiate between the target tissue and the surrounding healthy tissue. FPs like the KillerRed KRED used here can be activated by excitation with visible day-light for emitting active electrons which produce reactive oxygen species ROS resulting in photokilling processes. It is a given that the extent of the KRED s cell toxicity depends on its subcellular localization. Evidences are documented that the nuclear lamina as well as especially the chromatin are critical targets for KRED-mediated ROS-based DNA damaging. Here we investigated the damaging effects of the KRED protein fused to the nuclear lamina and to the histone H2A DNA-binding protein. We detected a frequency of DNA strand breaks dependent first on the illumination time and second on the spatial distance between the localization at the chromatin and the site of ROS production. As a consequence we could identify defined DNA bands with 200 400 and 600 bps as most .