CS298-4, Seminar on Self-Assembly
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Monday December 5, 2005, 4:10pm-5:30pm,
in 380 Soda Hall.
Zack Norwood presents:
"Membrane Self-Assembly Processes: Steps Toward the First Cellular Life"
by PIERRE-ALAIN MONNARD* AND DAVID W. DEAMER
Department of Chemistry and Biochemistry, University of California Santa Cruz
This review addresses the question of the origin of life, with emphasis
on plausible boundary structures that may have initially provided cellular
compartmentation. Some form of compartmentation is a necessary prerequisite
for maintaining the integrity of interdependent molecular systems
that are associated with metabolism, and for permitting variations required
for speciation. The fact that lipid-bilayer membranes define boundaries of
all contemporary living cells suggests that protocellular compartments
were likely to have required similar, self-assembled boundaries.
Amphiphiles such as short-chain fatty acids, which were presumably available on
the early Earth, can self-assemble into stable vesicles that encapsulate
hydrophilic solutes with catalytic activity. Their suspensions in aqueous
media have therefore been used to investigate nutrient uptake across simple
membranes and encapsulated catalyzed reactions, both of which would
be essential processes in protocellular life forms.
© 2002 Wiley-Liss, Inc.
THE ANATOMICAL RECORD 268:196 –207 (2002)
Ranjana Sahai presents:
"Self-assembled Micro-Devices Driven by Muscle"
JIANZHONG XI, JACOB J. SCHMIDT and CARLO D. MONTEMAGNO
UCLA Department of Bioengineering
Current procedures for manual extraction of mature muscle tissue in
micromechanical structures are time consuming and can damage the living
components. To overcome these limitations, we have devised a new system
for assembling muscle-powered microdevices based on judicious
manipulations of materials phases and interfaces. In this system,
individual cells grow and self-assemble into muscle bundles that are
integrated with micromechanical structures and can be controllably
released to enable free movement. Having realized such an assembly with
cardiomyocytes we demonstrate two potential applications: a force
transducer able to characterize in situ the mechanical properties of
muscle and a self-assembled hybrid (biotic/abiotic) microdevice that
moves as a consequence of collective cooperative contraction of muscle
bundles. Because the fabrication of silicon microdevices is independent
of the subsequent assembly of muscle cells, this system is highly
versatile and may lead to the integration of cells and tissues with a
variety of other microstructures.
NATURE MATERIALS: - Published online: 16 January 2005
Page Editor: Carlo H. Séquin