In multicellular animals, organ size, cell size and total organism size are regulated by signaling through the insulin receptor and TOR signaling pathways. The ribosomal protein S6 kinase is a key component of these pathways. It has been shown that mice or Drosophila lacking this kinase have a reduced body size that is associated with a decrease in cell size. Ectopic expression of activated or dominant negative transgenic variants of the Drosophila homolog of ribosomal S6 kinase (dS6K) has been shown to cause phenotypes that are consistent with a role for dS6K in growth, but whether the phenotypes were due to changes in cell size, cell number or other causes has not been shown. Here we show that ectopic expression of dS6K transgenes in the posterior wing compartment alters compartment size primarily by changes in cell size.

Included in

Biology Commons