Download Studies on the in vivo and in vitro dynamics of the bacterial MinD

Studies on the in vivo and in vitro Dynamics of the Bacterial MinD
Cytoskeleton
林以立 Yii-Lih Lin1,5、沈介磐 Jie-Pan Shen1,5、賴欣梅 Hsin-Mei Lai2,6、謝正偉 Cheng-Wei Hsieh2、
史有伶 Yu-Ling Shih2,6*、周家復 Chia-Fu Chou1,3,4*
1Institute of Physics, 2Institute of Biological Chemistry, 3Research Center for Applied Sciences,
4Genomics Research Center, Academia Sinica, Taipei, Taiwan
5Nano Science and Technology Program, Taiwan International Graduate Program,
Academia Sinica, Taipei, Taiwan
6Institute of Biochemical Science, National Taiwan University, Taipei, Taiwan
*Correspondence e-mail address: [email protected], [email protected]
The cell division in Escherichia coli requires the septal machinery to be
precisely placed at the middle of a cell. The dynamic pole-to-pole oscillation of
the Min
system is
critical
to
the
division
site
placement
and
consequently prevents the inadequate division which results in the production of
unequal-sized daughter cells. The MinD cytoskeleton is the central participant of
this process. The mechanism of oscillation has been proposed to underlie cycles
of rapid polymerization and depolymerization of the MinD protein filaments
through the MinE-regulated ATP binding and hydrolysis in MinD[1].
Our goals are to characterize MinD dynamics both in vivo and in vitro
through: (1) analysis of MinD oscillation patterns in E. coli when cells are
confined in microfluidic channels of defined shapes, and (2) in vitro
reconstruction of MinD protein filaments undergoing the dynamic processes of
polymerization and depolymerization. We have currently entrapped and
reshaped E. coli cells within micro-chambers. Moreover, we have observed that
purified MinD can interact with liposome and form extended filamentous
structures in our in vitro system. Fluorescence and total internal reflection (TIRF)
microscopy will be used to further study the MinD oscillation patterns in vivo and
protein polymerization and depolymerization processes in vitro.
1. Rothfield, L., A. Taghbalout, and Y.L. Shih, Spatial control of bacterial division-site placement.
Nature Reviews Microbiology, 2005. 3(12): p. 959-968.