LABEL-FREE MONITORING OF CELL SIGNALLING PROCESSES THROUGH AFM-BASED FORCE MEASUREMENTS - Life at the Nanoscale: Atomic Force Microscopy of Live Cells - page 356

Intracellular Ca 2+ level is well known to regulate several intracellular
kinases and calcium-binding proteins. It is also directly involved in the
polymerization of the g-actin monomer into polymeric f-actin ilaments,
making the actin content a dynamic component of the cytoskeleton. Indeed,
several actin regulatory cytoskeletal proteins are regulated by calcium,
such as calmodulin, 32 and CaMKII, 33,34 which are involved in motility and
(a)
(b)
(c)
(d)
Figure 17.5. Simultaneous monitoring of intracellular calcium and cell mechanical
luctuation in AT 1 -transfected HEK-293 cells stimulated by AngII. (a) Stimulation
of the AT 1 -receptor leads to the elevation of the cytoplasmic calcium pool. (b)
Mechanical response recorded together with (c) intracellular Ca 2+ concentration
evaluated using the ratiometric luorescent calcium indicator FURA 2/AM. (d)
Fluorescence micrographs of the FURA-2/AM loaded cells at different time of AT 1 -
receptor stimulation. The luorescence intensity in (c) was evaluated using the ratio
of the emission at 510 nm for sequential excitation at 340 and 380 nm.