Putting randomness to work: unique form of nanoscale random motion may drive key cellular functions

of a phosphate -- releases from the microtubule.
  • ATP hydrolysis makes the switch mechanism irreversible. Though ATP normally provides energy for macromolecular synthesis, Fox argues that in motor proteins ATP performs a switching role, changing the protein conformation and its binding affinity.
  • The unbound head -- just 5-7 nanometers in diameter -- is moved about randomly by Brownian motion in the cellular fluid until it encounters a new site where it can bind. Reported in the early 1800s by biologist Robert Brown, Brownian motion is the irregular activity of tiny particles suspended in a fluid. It results from the thermally driven movement of molecules in a fluid, the velocity of the particles depending on the temperature temperature.
  • Because of structural limits in the kinesin and spacing of binding sites on the microtubules, the moving head can reach only one possible binding site -- 8 nanometers past the bound head, which temporarily remains attached to the microtubule.
  • The head binds to the new site, moving the kinesin and its cargo about 8 nanometers along the microtubule.
  • The process quickly starts anew with the original two heads in interchanged positions.
  • "Normally, Brownian motion cannot do anything concerted or with directionality, because it is random," Fox explained. "But what happens here is a random process in a system that has asymmetric boundary conditions created by the ATP switching. That makes it possible to get a net directed motion along the microtubule."

    The model described by Fox and post-doctoral colleague Mee Hyang Choi depends on two unique properties of structures at the nanometer-scale: thermal energy can be a robust source of power, and random motion occurs very rapidly.

    "Normally, we would t

    Contact: John Toon
    Georgia Institute of Technology Research News

    Page: 1 2 3 4

    Related biology news :

    1. Putting energy into heart protection
    2. Putting GPS to work, researchers shed light on road-following by pigeons
    3. Putting genes in a pill
    4. Putting microRNAs in their place
    5. Putting muscle in the nucleus
    6. Putting muscle in the nucleus
    7. Putting a price tag on paradise
    8. Putting medical research on-line to give patients the information they need
    9. Putting Doesnt Pollute, Research Finds
    10. Putting A Price Tag On Pollution
    11. Putting Down Your Roots: How Plants Know To Do It

    Post Your Comments:

    (Date:6/23/2017)... N.Y. and ITHACA, N.Y. ... ) and Cornell University, a leader in dairy research, ... with bioinformatics designed to help reduce the chances that ... With the onset of this dairy project, Cornell University ... Consortium for Sequencing the Food Supply Chain, a food ...
    (Date:5/23/2017)... , May 23, 2017  Hunova, the first robotic gym for the ... been officially launched in Genoa, Italy . The first ... and the USA . The technology was developed ... market by the IIT spin-off Movendo Technology thanks to a 10 million ... News Release, please click: ...
    (Date:5/16/2017)... May 16, 2017   Bridge Patient Portal ... and MD EMR Systems , an electronic ... for GE, have established a partnership to build ... and the GE Centricity™ products, including Centricity Practice ... These new integrations will allow healthcare ...
    Breaking Biology News(10 mins):
    (Date:10/11/2017)...  VMS BioMarketing, a leading provider of patient support solutions, ... Educator (CNE) network, which will launch this week. The VMS ... care professionals to enhance the patient care experience by delivering ... health care professionals to help women who have been diagnosed ... ...
    (Date:10/10/2017)... DIEGO, CALIF. (PRWEB) , ... October 10, 2017 , ... ... as part of its corporate rebranding initiative announced today. The bold new look ... its reach, as the company moves into a significant growth period. , It will ...
    (Date:10/10/2017)... , Oct. 10, 2017 SomaGenics announced the ... NIH to develop RealSeq®-SC (Single Cell), expected to be ... small RNAs (including microRNAs) from single cells using NGS ... the need to accelerate development of approaches to analyze ... "New techniques for measuring levels of mRNAs ...
    (Date:10/9/2017)... ... ... At its national board meeting in North Carolina, ARCS® Foundation ... Physics and Astronomy, has been selected for membership in ARCS Alumni Hall of ... Breakthrough Prize in Fundamental physics for the discovery of the accelerating expansion of the ...
    Breaking Biology Technology:
    Cached News: