Speaker
Description
Organ growth during development is orchestrated by a combination of patterning, cell
proliferation, and morphogenesis, but the extent in which these contributions are
integrated into a multi-scale process is largely unknown. The developing wing of the fruit
fly, Drosophila melanogaster, offers an excellent experimental model to address this
question because there is a broad knowledge of the molecular players that drive
patterning and growth. Previous work has revealed that the gene regulatory network that
drives the expansion of the gene that determines cell fate, also involves the nuclear
translocation of the Hippo effector, Yorkie (Yki), which has been extensively reported as
a source of driving an excess of cell proliferation in overexpression conditions. However,
it is unclear if wild-type Yki levels participate in normal developmental growth. We
found that nuclear Yki levels moderately and transiently increase prior to wing cell
differentiation. We then used mathematical modelling to show that this result is
consistent with the gene network of the system and built a multi-scale molecular/tissue
model to investigate the possible role of this transient nuclear Yki as a mechanism that
transiently contribute to organ growth. This modelling-driven hypotheses-generation
approach uncovers a key role of transient effects that are often neglected when averaging
over space and time in classical developmental studies.emphasized text
