Arts and Humanities | Life Sciences | Physical Sciences and Mathematics | Social and Behavioral Sciences
Animal tissues must execute highly ordered and complex processes in order to perform their functions. Exocrine tissues are unique organs that secrete specialized products into a centralized cavity for short-term storage and later expulsion to an outside surface. Using advanced genetic and cell-biology imaging techniques, the Andrew Andres laboratory has been able to recapitulate one exocrine response—secretion of packaged proteins in response to a steroid signal in live tissues during real time. Pictured are four discretely timed snapshots of this process in which the cargos (fluorescently colored inclusions) are directed to the lumen (central cavity) of the tissue. This system has allowed the Andres Lab to test the role of scores of individual candidate molecules in a process that is conserved between insects and humans. Our lab has shown that a reconfiguration of ordinary muscle proteins (actin and myosin) organizes as dynamic shells around dumping structures. This shell is needed to squeeze cargoes out of cells into a lumen that becomes engorged and pressurized with accumulated product.