Translocation of a Polymer through a Crowded Channel under Electrical Force

The translocation of a polymer chain through a crowded cylindrical channel is studied using the Langevin dynamics simulations. The influences of the field strength F, the chain length N, and the crowding extent rho on the translocation time are evaluated, respectively. Scaling relation tau similar to F-alpha is observed. With the crowding extent rho increasing, the scaling exponent alpha becomes large. It is found that, for noncrowded channel, translocation probability drops when the field strength becomes large. However, for highcrowded channel, it is the opposite. Moreover, the translocation time and the average translocation time for all segments both have exponential growth with the crowding extent. The investigation of shape factor <delta > shows maximum value with increasing of the number of segments outside s. At last, the number of segments inside channel N-in in the process of translocation is calculated and a peak is observed. All the information from the study may benefit protein translocation.