1bg2
HUMAN UBIQUITOUS KINESIN MOTOR DOMAIN
OverviewOverview
Kinesin is the founding member of a superfamily of microtubule based motor proteins that perform force-generating tasks such as organelle transport and chromosome segregation. It has two identical approximately 960-amino-acid chains containing an amino-terminal globular motor domain, a central alpha-helical region that enables dimer formation through a coiled-coil, and a carboxy-terminal tail domain that binds light chains and possibly an organelle receptor. The kinesin motor domain of approximately 340 amino acids, which can produce movement in vitro, is much smaller than that of myosin (approximately 850 amino acids) and dynein (1,000 amino acids), and is the smallest known molecular motor. Here, we report the crystal structure of the human kinesin motor domain with bound ADP determined to 1.8-A resolution by X-ray crystallography. The motor consists primarily of a single alpha/beta arrowhead-shaped domain with dimensions of 70 x 45 x 45 A. Unexpectedly, it has a striking structural similarity to the core of the catalytic domain of the actin-based motor myosin. Although kinesin and myosin have virtually no amino-acid sequence++ identity, and exhibit distinct enzymatic and motile properties, our results suggest that these two classes of mechanochemical enzymes evolved from a common ancestor and share a similar force-generating strategy.
About this StructureAbout this Structure
1BG2 is a Single protein structure of sequence from Homo sapiens. The following page contains interesting information on the relation of 1BG2 with [Kinesin]. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of the kinesin motor domain reveals a structural similarity to myosin., Kull FJ, Sablin EP, Lau R, Fletterick RJ, Vale RD, Nature. 1996 Apr 11;380(6574):550-5. PMID:8606779 Page seeded by OCA on Fri May 2 11:27:55 2008