RTP and Tus: Difference between revisions
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'''Differential Binding Affinity''' | '''Differential Binding Affinity''' | ||
[[Image:RTP_DBA_Model.jpg|300px| | [[Image:RTP_DBA_Model.jpg|300px|right|thumb| Differential Binding Affinity Model proposed by Kralicek ''et al.'' in 1997. | ||
Image from Duggin ''et al.'', 2004. ]] | Image from Duggin ''et al.'', 2004. ]] | ||
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The entire concept of a “molecular clamp” in fork arrest has since been refuted by mutational studies performed by Duggin ''et al.'' in 2004. After creating mutant DNA Ter sites and analysing the resulting efficiency of replication fork arrest, Duggin ''et al.'' found that mutations which caused decreased affinity of RTP for the proximal half of the terminator DNA (i.e. the half which faces the approaching replisome) did not necessarily decrease fork arrest efficiency, and that increased proximal site affinity did not increase fork arrest efficiency. These results were inconsistent with the differential binding affinity model and induced conformational change, suggesting other factors apart from DNA-protein binding must also be responsible for replication fork arrest by RTP <ref>Duggin IG, Matthews JM, Dixon, NE, Wake RG, Mackay JP (2004) A Complex Mechanism Determines Polarity of DNA Replication Fork Arrest by the Replication Terminator Complex of ''Bacillus subtilis''. ''The Journal of Biological Chemistry'' 280(13): 13105-13113.</ref>. | The entire concept of a “molecular clamp” in fork arrest has since been refuted by mutational studies performed by Duggin ''et al.'' in 2004. After creating mutant DNA Ter sites and analysing the resulting efficiency of replication fork arrest, Duggin ''et al.'' found that mutations which caused decreased affinity of RTP for the proximal half of the terminator DNA (i.e. the half which faces the approaching replisome) did not necessarily decrease fork arrest efficiency, and that increased proximal site affinity did not increase fork arrest efficiency. These results were inconsistent with the differential binding affinity model and induced conformational change, suggesting other factors apart from DNA-protein binding must also be responsible for replication fork arrest by RTP <ref>Duggin IG, Matthews JM, Dixon, NE, Wake RG, Mackay JP (2004) A Complex Mechanism Determines Polarity of DNA Replication Fork Arrest by the Replication Terminator Complex of ''Bacillus subtilis''. ''The Journal of Biological Chemistry'' 280(13): 13105-13113.</ref>. | ||
<Structure load='2EFW' size='400' frame='true' align='right' caption='RTP complexed with Ter DNA (Vivian ''et al'' 2007)' scene='Insert optional scene name here' /> | |||
'''Helicase Binding''' | '''Helicase Binding''' | ||