Results tagged “DNA” from The SIBYLS Beamline

Two related manuscripts appear in the April 15 issue of CELL reporting results endo and exo nucleases important for DNA repair. Both groups of researchers made extensive use of the MX capabilities of the SIBYLS beamline to collect critical crystallographic data. The crystal structures of human flap endonuclease (FEN1) in complex with both substrate and product forms of DNA were reported by Susan Tsutakawa et al. in the following manuscript:

Published simultaneously by Jill Orans et al is the crystal structure of human exonuclease 1 in complex with DNA substrate.

Together these two manuscripts present exciting insights into the molecular principles governing diverse endo- and exonucleolytic cleavage specificities of members of the RAD2/FEN superfamily of nucleases, which have critical roles in DNA replication and maintenance.

UC Berkeley researchers, James Berger and Nathan Thomsen, used the SIBYLS beamline to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through it’s interior. The rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain. The results were published in the Oct 30th issue of Cell, and have recently been written up as an ALS scientific highlight.

UC Berkeley researchers, James Berger and Nathan Thomsen, used the SIBYLS beamline to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through it’s interior. The rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain. The results were published in the Oct 30th issue of Cell, and have recently been written up as an ALS scientific highlight.