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Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

Student, Craig T Martin, Michael Webster

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 [[Image:RTP a3 DNA binding.png | thumb | upright=1.2| left| DNA-binding interactions of the a3 helix of RTP.]]
-When an RTP dimer binds to a TerA or TerB site, the basic residues of the a3 helix are positioned in the major grooven and the beta ribbon rests at the minor groove. Non-specific ionic interactions between the N-terminus and the DNA backbone stabilise the complex.
+When an RTP dimer binds to a TerA or TerB site, the basic residues of the α3 helix are positioned in the major groove, and the β-ribbon rests within the minor groove. Non-specific ionic interactions between the N-terminus and the DNA backbone stabilise the complex.
-It is known, with some certainty, that the RTP dimer adopts an asymmetric arrangement upon binding of the TerB site. In the C110S mutant complexed with the native TerB sequence (2EFW), the two subunits interact differently with the DNA bases to produce wing-up and wing-down conformations. These can be distinguished by the angle the a2 helix makes with the a3 helix. It is likely that asymmetry is also introduced when the RTP dimer binds to the TerA site but the crystal structure of this complex has not been solved?
+It is known with some certainty that the RTP dimer adopts an asymmetric arrangement upon binding of the TerB site. In the [[2efw| C110S mutant]] complexed with the native TerB sequence, the two subunits interact differently with the DNA bases to produce wing-up and wing-down conformations. These can be distinguished by the angle the a2 helix makes with the a3 helix indicated in this <scene name='Sandbox20/2efw/14'>model</scene>. It is likely that asymmetry is also introduced when the RTP dimer binds to the TerA site, but the crystal structure of this complex has not been solved.
 Although the TerA site inherently has a lower binding affinity for RTP, as evident from the larger dissociation constant associated with the RTP-TerA complex, positive cooperativity from the binding of RTP to TerB facilitates the binding of RTP to TerA. It is proposed that RTP bends the DNA at the TerB site in a manner that favours RTP binding at TerA. The RTP dimer at TerB may also present a surface for stabilising interactions with the dimer at TerA. This is believed to happen through the b1 loop and b3 strand (need to standardise the names)
-The asymmetry of the dimer is shown by the names 'wing up' and 'wing down'. It is measured by the angle between the a2 and a3 heices, as shown <scene name='Sandbox20/2efw/14'>by clicking here</scene>.
 === Replication Termination Activity===