title: Specific insulin-like peptides encode sensory information to regulate distinct developmental processes.
abstract: An insulin-like signaling pathway mediates the environmental influence on the switch between the C. elegans developmental programs of reproductive growth versus dauer arrest. However, the specific role of endogenous insulin-like peptide (ILP) ligands in mediating the switch between these programs remains unknown. C. elegans has 40 putative insulin-like genes, many of which are expressed in sensory neurons and interneurons, raising the intriguing possibility that ILPs encode different environmental information to regulate the entry into, and exit from, dauer arrest. These two developmental switches can have different regulatory requirements: here we show that the relative importance of three different ILPs varies between dauer entry and exit. Not only do we find that one ILP, ins-1, ensures dauer arrest under harsh environments and that two other ILPs, daf-28 and ins-6, ensure reproductive growth under good conditions, we also show that daf-28 and ins-6 have non-redundant functions in regulating these developmental switches. Notably, daf-28 plays a more primary role in inhibiting dauer entry, whereas ins-6 has a more significant role in promoting dauer exit. Moreover, the switch into dauer arrest surprisingly shifts ins-6 transcriptional expression from a set of dauer-inhibiting sensory neurons to a different set of neurons, where it promotes dauer exit. Together, our data suggest that specific ILPs generate precise responses to dauer-inducing cues, such as pheromones and low food levels, to control development through stimulus-regulated expression in different neurons.
authors.affiliation: Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland.
authors.forename: Astrid
authors.initials: A
authors.lastname: Cornils
authors.forename: Mario
authors.initials: M
authors.lastname: Gloeck
authors.forename: Zhunan
authors.initials: Z
authors.lastname: Chen
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Joy
authors.initials: J
authors.lastname: Alcedo
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D004625:Embryo, Nonmammalian; D018507:Gene Expression Regulation, Developmental; D007328:Insulin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D061385:Insulins; D008136:Longevity / Q000235:genetics / Q000502:physiology; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D036361:Peptide Hormones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction; D013002:Somatomedins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D013534:Survival / Q000502:physiology
chemical_list: D029742:Caenorhabditis elegans Proteins; D007328:Insulin; D061385:Insulins; D010446:Peptide Fragments; D036361:Peptide Hormones; D013002:Somatomedins; C473608:daf-28 protein, C elegans; C424903:ins-1 protein, C elegans; D011972:Receptor, Insulin