EN
Insulin-like peptides (ILPs) and growth factors (IGFs) not only regulate development, growth, reproduction, metabolism, stress resistance, and lifespan, but also certain behaviors and cognitive functions. ILPs, IGFs, their tyrosine kinase receptors and downstream signaling components have been largely conserved over animal evolution. Eight ILPs have been identified in Drosophila (DILP1-8) and they display cell and stage specific expression patterns. One insulin receptor, dInR, is known in Drosophila and most other invertebrates. Nevertheless the different DILPs are independently regulated transcriptionally and appear to have partly distinct functions, with some redundancy. I will discuss what is known about regulation of production and release of DILPs in Drosophila with focus on insulin signaling in the daily life of the adult fly. Under what conditions are DILP-producing cells (IPCs) activated and which factors have been identified in control of IPC activity in flies? The brain IPCs that produce DILP2, 3 and 5 are targeted by a leptin-like molecule and DILP6 from the fat body. Also a few neurotransmitters and neuropeptides, like serotonin, octopamine, GABA, short neuropeptide F (sNPF), corazonin and tachykinin-related peptide have been identified as regulators of IPCs in Drosophila. I also discuss physiological conditions under which IPC activity may be regulated, including nutritional states, stress and diapause induction.