DNA damage stabilizes interaction of CSB with the transcription elongation machinery
The Cockayne syndrome B (CSB) protein is essential for transcription-coupled DNA repair (TCR), which is dependent on RNA polymerase II elongation. TCR is required to quickly remove the cytotoxic transcription-blocking DNA lesions. Functional GFP-tagged CSB, expressed at physiological levels, was homogeneously dispersed throughout the nucleoplasm in addition to bright nuclear foci and nucleolar accumulation. Photobleaching studies showed that GFP-CSB, as part of a high molecular weight complex, transiently interacts with the transcription machinery. Upon (DNA damage-induced) transcription arrest CSB binding these interactions are prolonged, most likely reflecting actual engagement of CSB in TCR. These findings are consistent with a model in which CSB monitors progression of transcription by regularly probing elongation complexes and becomes more tightly associated to these complexes when TCR is active.
|Keywords||*DNA Damage, *Transcription, Genetic, Active Transport, Cell Nucleus, Cell Line, Cell Nucleus/metabolism, Cells, Cultured, Cockayne Syndrome/metabolism, Computer Simulation, DNA Helicases/*chemistry/metabolism, DNA Repair, DNA, Complementary/metabolism, DNA-Binding Proteins/genetics, Fibroblasts/metabolism, Green Fluorescent Proteins, Humans, Image Processing, Computer-Assisted, Immunoblotting, Kinetics, Light, Luminescent Proteins/metabolism, Microscopy, Microscopy, Fluorescence, Protein Binding, RNA Polymerase II/chemistry, Recombinant Fusion Proteins/chemistry/metabolism, Research Support, Non-U.S. Gov't, Software, Time Factors, Ultraviolet Rays, Xeroderma Pigmentosum Group A Protein|
van den Boom, V., Citterio, E., Hoogstraten, D., Zotter, A., van Cappellen, W.A., Houtsmuller, A.B., … Egly, J-M.. (2004). DNA damage stabilizes interaction of CSB with the transcription elongation machinery. The Journal of Cell Biology. Retrieved from http://hdl.handle.net/1765/8360