Open Close
Okamoto, N., Nakamori, R., Murai, T., Yamauchi, Y., Masuda, A., Nishimura, T. (2013). A secreted decoy of InR antagonizes insulin/IGF signaling to restrict body growth in Drosophila.  Genes Dev. 27(1): 87--97.
FlyBase ID
Publication Type
Research paper

Members of the insulin peptide family have conserved roles in the regulation of growth and metabolism in a wide variety of metazoans. Drosophila insulin-like peptides (Dilps) promote tissue growth through the single insulin-like receptor (InR). Despite the important role of Dilps in nutrient-dependent growth control, the molecular mechanism that regulates the activity of circulating Dilps is not well understood. Here, we report the function of a novel secreted decoy of InR (SDR) as a negative regulator of insulin signaling. SDR is predominantly expressed in glia and is secreted into the hemolymph. Larvae lacking SDR grow at a faster rate, thereby increasing adult body size. Conversely, overexpression of SDR reduces body growth non-cell-autonomously. SDR is structurally similar to the extracellular domain of InR and interacts with several Dilps in vitro independent of Imp-L2, the ortholog of the mammalian insulin-like growth factor-binding protein 7 (IGFBP7). We further demonstrate that SDR is constantly secreted into the hemolymph independent of nutritional status and is essential for adjusting insulin signaling under adverse food conditions. We propose that Drosophila uses a secreted decoy to fine-tune systemic growth against fluctuations of circulating insulin levels.

PubMed ID
PubMed Central ID
PMC3553286 (PMC) (EuropePMC)
Associated Information
Associated Files
Other Information
Secondary IDs
    Language of Publication
    Additional Languages of Abstract
    Parent Publication
    Publication Type
    Genes Dev.
    Genes & Development
    Publication Year
    Data From Reference