Open AccessRecombinant kinesin motor domain binds to beta-tubulin and decorates microtubules with a B surface lattice.
Author(s) -
Young Ho Song,
Eckhard Mandelkow
Publication year - 1993
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.90.5.1671
Subject(s) - microtubule , tubulin , kinesin , biophysics , dimer , chemistry , microbiology and biotechnology , biology , organic chemistry
We have expressed the recombinant squid kinesin head domain in Escherichia coli and studied its interaction with microtubules. The head is active as a microtubule-stimulated ATPase and binds to microtubules, but it does not support microtubule gliding by itself. The head binds to both microtubules and depolymerized tubulin. In each case the zero-length crosslinker 1-ethyl-3-[3-dimethylamino)propyl] carbodiimide induces a bond specifically to beta- but not alpha-tubulin. The head decorates brain microtubules with an 8-nm axial spacing. Thus the stoichiometry is one kinesin head per tubulin dimer. The lattice is that of flagellar B-tubules, implying that reassembled microtubules are not symmetric. Moreover, the A- and B-tubules of intact flagellar outer doublets are both decorated with a B lattice. This suggests that the B lattice is a general property of microtubules.