27 Mar 2009
Tsvi Tlusty
Weizmann Institute of Science
Israel
We will discuss the problem of molecular recognition during the process of homologous recombination. A general question to be examined in this context is the effect of conformational changes on the quality of molecular recognition.
Recombination requires detecting homologous DNAs within a huge variety of heterologous sequences. During the detection process the participating DNAs are extended by 50-60%. What is the role of this stretch, which involves a considerable amount of energy?
Looking at the DNA recognition process in terms of a signal detection problem, it appears that the observed DNA extension maximizes the ability to detect homologous sequences. This suggests a generic design principle for molecular recognition systems, termed conformational proofreading, in which the expenditure of energy to induce conformational changes enhances the quality of detection.