While major advances have been made in our understanding of the progressive tissue specification during development, the translation of these regulatory cues into the remodelling of the shape of individual cells remains poorly understood.
We address this question focusing on the genetic networks that determine morphological differentiation of the Drosophila embryonic epidermis. Previous work has demonstrated the key role of a transcription factor, Shavenbaby (Svb), in determining the pattern of epidermal cell morphogenesis during development, and its diversification during evolution. Svb defines a subpopulation of epidermal cells that produce robust actin-rich apical extensions, called denticles or trichomes. Genome-wide profiling of Svb downstream targets provides access to the comprehensive set of cellulars effectors responsible for epidermal cell remodelling, identifying genes regulating the organization of cytoskeleton, membrane, extracellular matrix (ECM), etc...
We further investigate the in vivo functions of several cellular effectors identified here, choosing those homologous to gene products implicated in human pathologies. Together, our studies have uncovered the unexpected role of apical ECM reorganization for cell morphogenesis. Also, our works provide novel insights into the molecular mechanisms that regulate actin organization during invasive cell migration and cell division.