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BIOPHYSICAL SOCIETY NEWSLETTER
12
AUGUST
2016
Biophysical Journal
Know the Editors
Kazuhiro Oiwa
National Institute of Informa-
tion and Communications
Technology, Tokyo
Editor, Molecular Machines,
Motors, and Nanoscale
Biophysics
Q:
What are you currently working on?
Our research group has focused on understand-
ing the mechanisms of dyneins and eukaryotic
flagellar motility. Dyneins are microtubule-based
protein motors that drive cilia/flagella, and play
important roles in a variety of essential intracel-
lular motility. Using in vitro motility assays and
single-molecule measurements, we have revealed
mechanical properties and regulations of axo-
nemal and cytoplasmic dyneins. Recently, we
adopted a bottom-up approach for our study on
dyneins and axonemes, in which well-character-
ized components are combined into a functional
assembly in order to reconstitute the original
functions in vitro. Advances in nanotechnology,
including DNA origami techniques, and in mo-
lecular biology make this approach feasible.
Q:
What are you currently working on
that excites you?
Collective motion of self-propelled particles is
my current interest. We found that microtubules
driven by surface-bound dyneins self-organized
into large-scale vortices. When I was observing
microtubule movement in a small 100 μm ×
100 μm area, large streams of microtubules acci-
dentally passed through the observation area. That
was my first encounter with the phenomenon.
Like the Nazca geoglyphs, a wide view enabled us
to recognize the large-scale vortex patterns formed
in an entire flow cell. We successfully showed this
process by a simple mathematical model, based on
only the smooth motion of single microtubules
and their local interaction (alignment of micro-
tubules on collision). Now, it is exciting for us to
extend the experiments to various types of dynein
in order to find a universal class of collective
motion.
Q:
What has been your most exciting
discovery as a biophysicist?
My most exciting discovery was the large configu-
ration change of an axonemal dynein molecule
coupled with nucleotide states. This was done in
collaboration with a group at the University of
Leeds. On electron micrographs, single particle
analysis of negatively stained axonemal dynein
revealed such large changes. From this work, I
learned that raw micrographs of negatively stained
molecules contain a wealth of structural informa-
tion, and I fully recognized the power of math-
ematics.
Q:
At a cocktail party of non-scientists,
how would you explain what you do?
Talking about the invisible things that happen
inside of our bodies is a good way to capture peo-
ple’s interest. First, I would ask the non-scientists
when and how symmetric breaks take place in our
body during development. Then I would explain
that a simple function of a group of tiny organ-
elles, called cilia, determines the development of
right–left asymmetry. This is a good introduction
to present to my audience, to explain to them the
importance of studying these organelles. It is also
an amazing example of our extraordinary biologi-
cal system, in which a small bias can be detected,
enhanced, and bring about change in a wide
ranges of scales. This is an attractive concept, not
only for scientists, but also for non-scientists.
Q:
How do you stay on top of all the
latest developments in your field?
My main way of staying up to date with the latest
research is to attend the Biophysical Society An-
nual Meeting and other international conferences.
Conferences are not only showcases of the latest
research, but they also provide rich sources for
novel ideas. Also, reading peer-reviewed literature
is, of course, unavoidable. My preference is the
review journals since they are handy for catching
up with the progress in the research fields.
Kazuhiro Oiwa