(16c) Connecting Exogenous Stimuli to Patterned Calcium Signalling in a Regulated Epithelial Microenvironment

Intercellular propagation of calcium ions (Ca²⁺) has been observed in a variety of tissues and is mediated by many different stimuli. Calcium signaling plays multiple roles in most cellular processes including cell cycle regulation. To better understand the role of Ca²⁺ signalling in development and homeostasis, we have developed a microfluidic chip which allows for controlled culture and stimulation of Drosophila imaginal wing discs under observation on a confocal microscope, a Regulated Epithelial Microenvironment microfluidic chip (REMChip). Key stimulation modalities include chemical perfusion, mechanical compression, mechanical tension, and electrical gradation.  Our initial results demonstrate that the wing disc can be cultured for up to 10 hours and that Ca²⁺ signalling is quiescent during mechanical compression, but once compression is removed a Ca²⁺ wave cascades throughout the disc. Through local wounding and growth factor stimulation, we have also quantified and analyzed the patterning of intercellular Ca²⁺ transients, which reflect the underlying mechanics and differentiate state of cells within the tissue.