title: Memoryless self-reinforcing directionality in endosomal active transport within living cells.
abstract: In contrast to Brownian transport, the active motility of microbes, cells, animals and even humans often follows another random process known as truncated Lévy walk. These stochastic motions are characterized by clustered small steps and intermittent longer jumps that often extend towards the size of the entire system. As there are repeated suggestions, although disagreement, that Lévy walks have functional advantages over Brownian motion in random searching and transport kinetics, their intentional engineering into active materials could be useful. Here, we show experimentally in the classic active matter system of intracellular trafficking that Brownian-like steps self-organize into truncated Lévy walks through an apparent time-independent positive feedback such that directional persistence increases with the distance travelled persistently. A molecular model that allows the maximum output of the active propelling forces to fluctuate slowly fits the experiments quantitatively. Our findings offer design principles for programming efficient transport in active materials.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, USA.
authors.forename: Kejia
authors.initials: K
authors.lastname: Chen
authors.affiliation: 1] Department of Materials Science, University of Illinois, Urbana, Illinois 61801, USA [2] Institute for Genomic Biology, University of Illinois, Urbana, Illinois 61801, USA.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: 1] Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801, USA [2] Department of Materials Science, University of Illinois, Urbana, Illinois 61801, USA [3] Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA [4] Department of Physics, University of Illinois, Urbana, Illinois 61801, USA [5] IBS Center for Soft and Living Matter, UNIST, Ulsan 689-798, South Korea.
authors.forename: Steve
authors.initials: S
authors.lastname: Granick
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D002477:Cells; D011992:Endosomes / Q000378:metabolism*
references.citation: Nature. 2012 Jun 28;486(7404):545-8
references.pmid: 22722867
references.citation: J Cell Biol. 2005 Dec 5;171(5):845-55
references.pmid: 16314429
references.citation: Nature. 2007 Jan 25;445(7126):406-9
references.pmid: 17251974
references.citation: Nature. 1999 Oct 28;401(6756):911-4
references.pmid: 10553906
references.citation: Nature. 2008 May 22;453(7194):495-8
references.pmid: 18497819
references.citation: Science. 2011 Jun 24;332(6037):1551-3
references.pmid: 21700872
references.citation: Proc Natl Acad Sci U S A. 2008 Mar 25;105(12 ):4609-14
references.pmid: 18347340
references.citation: Nat Mater. 2003 Nov;2(11):715-25
references.pmid: 14593396
references.citation: Science. 2014 May 30;344(6187):1031-5
references.pmid: 24876498
references.citation: Phys Rev Lett. 2012 Jul 13;109(2):028104
references.pmid: 23030209
references.citation: ACS Nano. 2013 Oct 22;7(10):8634-44
references.pmid: 23971739
references.citation: Phys Rev Lett. 1994 Nov 28;73(22):2946-2949
references.pmid: 10057243
references.citation: Phys Rev Lett. 2008 Dec 12;101(24):248103
references.pmid: 19113674
references.citation: Biophys J. 2006 Nov 1;91(9):3542-59
references.pmid: 16891360
references.citation: Trends Cell Biol. 2009 Sep;19(9):423-7
references.pmid: 19699642
references.citation: Proc Natl Acad Sci U S A. 2003 Oct 28;100(22):12771-5
references.pmid: 14566048
references.citation: Annu Rev Biophys. 2009;38:217-34
references.pmid: 19416067
references.citation: Phys Rev Lett. 2013 Nov 15;111(20):208102
references.pmid: 24289710
references.citation: Chemphyschem. 2012 Mar;13(4):1001-6
references.pmid: 22213552
references.citation: Curr Opin Cell Biol. 2008 Feb;20(1):41-7
references.pmid: 18226515
references.citation: Proc Natl Acad Sci U S A. 2014 Feb 25;111(8):2931-6
references.pmid: 24516153
references.citation: Nature. 2007 Oct 25;449(7165):1044-8
references.pmid: 17960243
references.citation: Proc Natl Acad Sci U S A. 2013 Feb 26;110(9):3375-80
references.pmid: 23401534
references.citation: Proc Natl Acad Sci U S A. 2005 Nov 29;102(48):17284-9
references.pmid: 16287974
references.citation: Proc Natl Acad Sci U S A. 2013 Mar 26;110(13):4911-6
references.pmid: 23479621
references.citation: Proc Natl Acad Sci U S A. 2013 Dec 17;110(51):20380-5
references.pmid: 24297895