Accueil  >  Séminaires  >  Understanding Molecular Mechanisms of Biological Error Correction
Understanding Molecular Mechanisms of Biological Error Correction
Par Anatoly B. Kolomeisky (Rice University)
Le 28 Mai 2019 à 11h00 - Salle de séminaires 5ème étage, Tour 32-33

Résumé

One of the most fascinating features of biological systems is the ability to sustain an
extraordinary high accuracy of all major cellular processes despite the stochastic nature of
underlying chemical processes. It is widely believed that such low errors are the result of the
error correcting mechanism known as a kinetic proofreading. However, there are contradicting
views on the balance of speed and accuracy in biological processes. We developed a
comprehensive theoretical framework that allowed us to quantitatively investigate the molecular
mechanisms of the proofreading using the method of first-passage processes. Within this
framework, we simultaneously analyzed speed and accuracy of the two fundamental biological
processes, DNA replication and tRNA selection during the translation. The results indicate that
speed-accuracy trade-off is not always observed, as usually assumed. However, when the trade-
off is present, the biological systems tend to optimize the speed rather than the accuracy of the
processes, as long as the error level is tolerable. Additional constraints due to the energetic cost
of proofreading also might play a role in the error correcting process. We present theoretical
arguments to explain these surprising observations. Other possible criteria for optimizing
biological systems are also discussed. Our theoretical findings provide a new microscopic picture
of how complex biological processes are able to function so fast with a high accuracy.