Role of intrinsic versus extrinsic cues in cell type determination during development and regeneration

All of the different cell types must be made during development. The process of generating different cell fates is controlled intrinsically (inside) by the highly co-ordinated control of turning genes on or off, but also influenced by extrinsic signals from the surrounding developing cells that signal which cell types are present. The developmental role of extrinsic signalling and how powerful these signals are in instructing regenerating cells to replace only the missing (degenerated/diseased) cells are unknown. Using the zebrafish retina model, in which the main intrinsic genes and cell types are known, we will study the role of extrinsic signals in normal development and its power in directing cell type choices during regeneration.