Imaging the Impact of Chemically Inducible Proteins on Cellular Dynamics In Vivo
231LN cells expressing tdTomato (red) and tunable E-cadherin-zsGreen-DD (green) were injected intravenously in the avian embryo and allowed to extravasate and proliferate into micrometastases. Representative maximum intensity projections are shown. A) In vivo treatment with 1.0 µM Shield-1 demonstrates transition from a mesenchymal morphology to an epithelial morphology and continued maintenance of the epithelial morphology over an extended period of time (>40 hrs). Formation of E-cadherin junctions is apparent at t = 0.5 hrs, increasing through 24 hrs. B) Representative micrometastatic colony expressing tunable E-cadherin-zsG-DD and treated with 0.2 µM Shield-1. No induction effect is observed with 0.2 µM Shield-1 in vivo. C) Single Z-plane slices of a representative micrometastastic colony expressing tunable E-cadherin-zsG-DD and treated with 0.5 µM Shield-1. These panels represent the stabilization effect induced by 0.5 µM Shield-1 over the 12 hour time course; E-cadh-zsG-DD is stabilized and junctions appear between 231LN cells. E-cadh-zsG-DD junctions between cells of the micrometastatic colony are highlighted by arrows. D) Panels represent the depletion effect in the same colony with depleted levels of 0.5 µM Shield-1; E-cadh-zsG-DD junctions gradually disperse over time and 231LN cells eventually revert to a mesenchymal morphology. All scale bars are 25 µm. E) Quantitation of E-cadh-zsG-DD signal in 231LN-tdTomato cells in a 4-dimension image set over the entire 28 hour time course.