| Controlling the Direction of Kinesin-Driven Microtubule Movements along Microlithographic Tracks Biophysical Journal, Volume 81, Issue 3, 1 September 2001, Pages 1555-1561 Yuichi Hiratsuka, Tetsuya Tada, Kazuhiro Oiwa, Toshihiko Kanayama and Taro Q.P. Uyeda Abstract Motor proteins are able to move protein filaments in vitro. However, useful work cannot be extracted from the existing in vitro systems because filament motions are in random directions on two-dimensional surfaces. We succeeded in restricting kinesin-driven movements of microtubules along linear tracks by using micrometer-scaled grooves lithographically fabricated on glass surfaces. We also accomplished the extraction of unidirectional movement from the bidirectional movements along the linear tracks by adding arrowhead patterns on the tracks. These “rectifiers” enabled us to construct microminiturized circulators in which populations of microtubules rotated in one direction, and to actively transport microtubules between two pools connected by arrowheaded tracks in the fields of micrometer scales. Abstract | Full Text | PDF (865 kb) |
| Platform U: Biotechnology & Bioengineering Biophysical Journal, Volume 94, Issue , 1 February 2008, Pages 307-310 Full Text | PDF (125 kb) |
| Actin Motion on Microlithographically Functionalized Myosin Surfaces and Tracks Biophysical Journal, Volume 77, Issue 2, 1 August 1999, Pages 1126-1134 Dan V. Nicolau, Hitoshi Suzuki, Shinro Mashiko, Takahisa Taguchi and Susumu Yoshikawa Abstract High-resolution e-beam patterning exposure of the surface of poly[(-butyl-methacrylate)--(methyl methacrylate)]—a common e-beam and deep-UV resist used in semiconductor microlithography—induced sharp changes in the surface hydrophobicity. These differences in hydrophobicity resulted in the selective attachment of heavy meromyosin to hydrophobic, unexposed surfaces. The movement of the actin filaments on myosin-rich and myosin-poor surfaces was statistically characterized in terms of velocity, acceleration, and angle of movement. The actin filaments have a smooth motion on myosin-rich surfaces and an uneven motion on myosin-poor surfaces. Interestingly, an excess of myosin sites has a slowing, albeit mild effect on the motion of the actin filaments. It was also found that the myosin-rich/myosin-poor boundary has an alignment-enforcement effect, especially for the filaments approaching the border from the myosin-rich side. Based on these results, we discuss the feasibility of building purposefully designed molecular motor arrays and the testing of the hypotheses regarding the functioning of the molecular motors. Abstract | Full Text | PDF (758 kb) |
Copyright © 1995 The Biophysical Society. All rights reserved.
Biophysical Journal, Volume 69, Issue 6, 2782-2789, 1 December 1995
doi:10.1016/S0006-3495(95)80151-7
Research Article
D.C. Turner, C. Chang, K. Fang, S.L. Brandow and D.B. Murphy
We show that microtubule polymers can be immobilized selectively on lithographically patterned silane surfaces while retaining their native properties. Silane films were chemisorbed on polished silicon wafers or glass coverslips and patterned using a deep UV lithographic process developed at the Naval Research Laboratory. Hydrocarbon and fluorocarbon alkyl silanes, as well as amino and thiol terminal alkyl silanes, were investigated as substrates for microtubule adhesion with retention of biological activity. Microtubules were found to adhere strongly to amine terminal silanes while retaining the ability to act as substrates for the molecular motor protein kinesin. Aminosilane patterns with linewidths varying from 1 to 50 microns were produced lithographically and used to produce patterns of selectively adhered microtubules. Microtubules were partially aligned on the patterned lines by performing the immobilization in a fluid flow field. Patterns were imaged with atomic force microscopy and differential interference contrast microscopy. Motility assays were carried out using kinesin-coated beads and observed with differential interference contrast microscopy. Kinesin bead movement on the patterned microtubules was comparable to movement on microtubule control surfaces.