Imp-L2, a putative homolog of vertebrate IGF-binding protein 7, counteracts insulin signaling in Drosophila and is essential for starvation resistance.

ABSTRACT:

Background

Insulin and insulin-like growth factors (IGFs) signal through a highly conserved pathway and control growth and metabolism in both vertebrates and invertebrates. In mammals, insulin-like growth factor binding proteins (IGFBPs) bind IGFs with high affinity and modulate their mitogenic, anti-apoptotic and metabolic actions, but no functional homologs have been identified in invertebrates so far.

Results

Here, we show that the secreted Imaginal morphogenesis protein-Late 2 (Imp-L2) binds Drosophila insulin-like peptide 2 (Dilp2) and inhibits growth non-autonomously. Whereas over-expressing Imp-L2 strongly reduces size, loss of Imp-L2 function results in an increased body size. Imp-L2 is both necessary and sufficient to compensate Dilp2-induced hyperinsulinemia in viv

SUBMITTER: Honegger B 

PROVIDER: S-EPMC2323038 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature