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Navigation Strategies of Motor Proteins on Decorated Tracks.

Bertalan Z, Budrikis Z, La Porta CA, Zapperi S - PLoS ONE (2015)

Bottom Line: Here, we show by numerical simulations that deterministic and random motor steps yield different outcomes when random obstacles decorate the microtubule tracks: kinesin moves faster on clean tracks but its motion is strongly hindered on decorated tracks, while dynein is slower on clean tracks but more efficient in avoiding obstacles.Further simulations indicate that dynein's advantage on decorated tracks is due to its ability to step backwards.Our results explain how different navigation strategies are employed by the cell to optimize motor driven cargo transport.

View Article: PubMed Central - PubMed

Affiliation: Institute for Scientific Interchange Foundation, Torino, Italy.

ABSTRACT
Motor proteins display widely different stepping patterns as they move on microtubule tracks, from the deterministic linear or helical motion performed by the protein kinesin to the uncoordinated random steps made by dynein. How these different strategies produce an efficient navigation system needed to ensure correct cellular functioning is still unclear. Here, we show by numerical simulations that deterministic and random motor steps yield different outcomes when random obstacles decorate the microtubule tracks: kinesin moves faster on clean tracks but its motion is strongly hindered on decorated tracks, while dynein is slower on clean tracks but more efficient in avoiding obstacles. Further simulations indicate that dynein's advantage on decorated tracks is due to its ability to step backwards. Our results explain how different navigation strategies are employed by the cell to optimize motor driven cargo transport.

No MeSH data available.


Related in: MedlinePlus

Velocity profiles for kinesin and dynein are largely unaffected by changes in the off-axis parameter pang.For the range of pang studied, 0.02 ≤ pang ≤ 0.6, changing pang does not affect the shape of the velocity profile except in the case of dynein with pang = 0.02, where dynein is faster than kinesin only for large ρ. Lines are guides to the eye; errorbars are smaller than the symbol size.
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pone.0136945.g006: Velocity profiles for kinesin and dynein are largely unaffected by changes in the off-axis parameter pang.For the range of pang studied, 0.02 ≤ pang ≤ 0.6, changing pang does not affect the shape of the velocity profile except in the case of dynein with pang = 0.02, where dynein is faster than kinesin only for large ρ. Lines are guides to the eye; errorbars are smaller than the symbol size.

Mentions: Even for the coordinated stepping of wild-type kinesin, helical motion confers and advantage over linear motion. Simulations of kinesin-1, which moves along a single protofilament, indicate that its motion is halted for any decoration fraction. The importance of sideways steps for navigation has also been identified experimentally [28]. We have tested a range of values for the off-axis parameter 0.02 ≤ pang ≤ 0.6 away from its wild-type values. We find that for pang ≳ 0.1 the fraction of off-axis steps does not make a large contribution to the motor protein velocity on decorated tracks, for both motor proteins, as shown in Fig 6.


Navigation Strategies of Motor Proteins on Decorated Tracks.

Bertalan Z, Budrikis Z, La Porta CA, Zapperi S - PLoS ONE (2015)

Velocity profiles for kinesin and dynein are largely unaffected by changes in the off-axis parameter pang.For the range of pang studied, 0.02 ≤ pang ≤ 0.6, changing pang does not affect the shape of the velocity profile except in the case of dynein with pang = 0.02, where dynein is faster than kinesin only for large ρ. Lines are guides to the eye; errorbars are smaller than the symbol size.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556374&req=5

pone.0136945.g006: Velocity profiles for kinesin and dynein are largely unaffected by changes in the off-axis parameter pang.For the range of pang studied, 0.02 ≤ pang ≤ 0.6, changing pang does not affect the shape of the velocity profile except in the case of dynein with pang = 0.02, where dynein is faster than kinesin only for large ρ. Lines are guides to the eye; errorbars are smaller than the symbol size.
Mentions: Even for the coordinated stepping of wild-type kinesin, helical motion confers and advantage over linear motion. Simulations of kinesin-1, which moves along a single protofilament, indicate that its motion is halted for any decoration fraction. The importance of sideways steps for navigation has also been identified experimentally [28]. We have tested a range of values for the off-axis parameter 0.02 ≤ pang ≤ 0.6 away from its wild-type values. We find that for pang ≳ 0.1 the fraction of off-axis steps does not make a large contribution to the motor protein velocity on decorated tracks, for both motor proteins, as shown in Fig 6.

Bottom Line: Here, we show by numerical simulations that deterministic and random motor steps yield different outcomes when random obstacles decorate the microtubule tracks: kinesin moves faster on clean tracks but its motion is strongly hindered on decorated tracks, while dynein is slower on clean tracks but more efficient in avoiding obstacles.Further simulations indicate that dynein's advantage on decorated tracks is due to its ability to step backwards.Our results explain how different navigation strategies are employed by the cell to optimize motor driven cargo transport.

View Article: PubMed Central - PubMed

Affiliation: Institute for Scientific Interchange Foundation, Torino, Italy.

ABSTRACT
Motor proteins display widely different stepping patterns as they move on microtubule tracks, from the deterministic linear or helical motion performed by the protein kinesin to the uncoordinated random steps made by dynein. How these different strategies produce an efficient navigation system needed to ensure correct cellular functioning is still unclear. Here, we show by numerical simulations that deterministic and random motor steps yield different outcomes when random obstacles decorate the microtubule tracks: kinesin moves faster on clean tracks but its motion is strongly hindered on decorated tracks, while dynein is slower on clean tracks but more efficient in avoiding obstacles. Further simulations indicate that dynein's advantage on decorated tracks is due to its ability to step backwards. Our results explain how different navigation strategies are employed by the cell to optimize motor driven cargo transport.

No MeSH data available.


Related in: MedlinePlus