Using Nanofluidic Channels to Probe the Dynamics of Rad51-DNA Filaments

Louise Helena Fornander, Fredrik Persson, Joachim Fritzsche, Joshua Araya, Philip Nevin, Penny Beuning, Mauro Modesti, Karolin Frykholm, Fredrik Westerlund
2014 Biophysical Journal  
furthermore suggest that MutS and its homologs are exquisitely tuned to bend DNA just enough to discriminate mismatches from canonical DNA. Moreover, the recognition of insertion/deletion-containing DNA also appears to require bending but at an even greater extent than mismatch-containing DNA. The simulation results are further discussed in the context of the overall mechanism of post-replication DNA repair. 3504-Pos Board B232 Single Molecule Dynamics Governing the Initiation of V(D)J
more » ... tion The recombination activating genes (RAG)1 and RAG2 perform V(D)J recombination by rearranging conserved recombination signal sequences (RSSs) to generate antigen-receptors during lymphopoiesis. However the orchestration of V(D)J recombination on biologically relevant (long) length scales has resisted experimental investigation. Here we develop singlemolecule assays to watch in real time as RAG1/2 and its co-factor HMGB1 carry out V(D)J recombination from start (RSS binding) to finish (hairpin formation) on long DNA molecules. We capture various intermediate states preceding hairpin formation, show how RAG1/2 and HMGB1 form bends on the DNA, demonstrate how the identity of the recombination signal sequence modulates bending with single bp resolution and show HMGB1 must compact DNA flanking RSSs to form hairpins. Our results provide single-molecule mechanistic insight into the orchestration of V(D)J recombination. 3505-Pos Board B233 Substrate Interactions of a Human DNA Alkyltransferase
doi:10.1016/j.bpj.2013.11.3830 fatcat:s3zulgebojhupo5stnytecmivy