Dynamic Mechanism Of DNA Polymerase? And Two-kinesin Assembly

Proteins are significant components in cells.Different proteins always have different structures and conduct different functions according to their conformations.Molecular motor proteins are typical ones that attract worldwide attentions.Molecular motors can use the chemical energy released from ATP hydrolysis to produce mechanical work.As a well-known type of motor proteins,DNA polymerase I is responsible for DNA replicaion.DNA polymerase I can move along DNA template and incorporate dNTP to synthesize new DNA strand.It is composed of a core domain and 5?-nuclease domain,which are connected by a polypeptide linker.It is an interesting topic to study the dynamic mechanism of DNA polymerase I.Here,we carry out deep studies on DNA polymerase I,and we reveal that the linker plays an important role in the function of DNA polymerase I.We find the linker possesses optimum number of residues and makes the 5?-nuclease domain transit most efficiently.Other proteins,such as DNA polymerase IV and T7 primase that have similar structure to DNA polymerase I,have similar results.Conventional kinesin is another type of motor proteins.It can transport cellular cargos and move along microtubules for seconds.Multiple kinesins can also work together processively,among which two-kinesin assembly is the simplest case.We conduct theoretical studies on dynamic characters of two-kinesin assembly,and we find that the coupling strength signicantly determines the velocity and stall force of the assembly.Besides,we find that the chemomechanical coupling can also influence the stall force.Our research methods include many computational simulations,such as molecular dynamic simulations,Monte Carlo simulations,Brownian dynamic simulations and theoretical modeling.The results we obtained are consistent with all relative experiments and some results are predictions for further experimatal study.More importantly,our researches and conclusions have general meanings and may be used to study dynamic mechanism of other molecular motor protiens.