Scientific
Goals
My research in the lab is focused on Eg5, a molecular
motor that plays a key role in separation of
chromosomes and formation of the bipolar microtubule
spindle during mitosis. The aim of my work
is to elucidate the structure and function of
full length tetrameric human Eg5, first as isolated
complexes and ultimately complexed with the spindle
within cells.
Isolated
Eg5 tetramers, supplemented with various markers
for distinct structural elements, will be imaged
using cryo-electron microscopy and tomography, and
structural data obtained by tomographic 3D reconstruction
or single particle 3D reconstruction if necessary.
Following this, Eg5 complexes in microtubule bundles
will be examined in several conformations by cryo-electron
tomography and volume averaging. This
should give us insight into nucleotide dependant
functional states of Eg5 in its primary role as a
microtubule organizer, and the underlying mechanistic
principles of how spindles are operated by motors
and microtubules.
Finally,
it is my goal to visualize Eg5 in its working state
within the cell. This will be achieved by preparing
ultrathin sections of cells embedded in vitreous
ice and structural data will be obtained again with
cryo-electron tomography. This will address
the importance of understanding how these motor complexes
act in their real-life environment in the presence
of many other factors such as non-motor microtubule
associated proteins.
Eg5’s
important role in facilitating mitosis makes it an
attractive target for cancer treatment. It
has been shown that a number of small molecule inhibitors,
such as monastrol, can specifically inhibit Eg5 causing
cell cycle arrest. The long-term goal of these
Eg5 structural studies is to obtain a model system
with which to test kinesin-related drugs with high-throughput
approaches as potential treatments for cancer and
other related diseases. |
