title: Adaptive Physiological Response to Perceived Scarcity as a Mechanism of Sensory Modulation of Life Span.
abstract: Chemosensation is a potent modulator of organismal physiology and longevity. In Drosophila, loss of recognition of diverse tastants has significant and bidirectional life-span effects. Recently published results revealed that when flies were unable to taste water, they increased its internal generation, which may have subsequently altered life span. To determine whether similar adaptive responses occur in other contexts, we explored the impact of sensory deficiency of other metabolically important molecules. Trehalose is a major circulating carbohydrate in the fly that is recognized by the gustatory receptor Gr5a. Gr5a mutant flies are short lived, and we found that they specifically increased whole-body and circulating levels of trehalose, but not other carbohydrates, likely through upregulation of de novo synthesis. dILP2 transcript levels were increased in Gr5a mutants, a possible response intended to reduce hypertrehalosemia, and likely a contributing factor to their reduced life span. Together, these data suggest that compensatory physiological responses to perceived environmental scarcity, which are designed to alleviate the ostensive shortage, may be a common outcome of sensory manipulation. We suggest that future investigations into the mechanisms underlying sensory modulation of aging may benefit by focusing on direct or indirect consequences of physiological changes that are designed to correct perceived disparity with the environment.
authors: Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor.
authors: Michael J
authors: MJ
authors: Waterson
authors: Program in Developmental Biology, Baylor College of Medicine; Houston, TX.
authors: Tammy P
authors: TP
authors: Chan
authors: Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor. Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor. Geriatrics Center, University of Michigan, Ann Arbor. spletch@umich.edu.
authors: Scott D
authors: SD
authors: Pletcher
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D004330:Drosophila / Q000502:physiology*; D029721:Drosophila Proteins / Q000097:blood / Q000235:genetics; D051034:Inhibitor of Apoptosis Proteins / Q000097:blood; D008136:Longevity / Q000502:physiology*; D009154:Mutation; D011956:Receptors, Cell Surface / Q000235:genetics; D013651:Taste Disorders / Q000503:physiopathology*; D014199:Trehalose / Q000097:blood
chemical_list: C111892:DIAP2 protein, Drosophila; D029721:Drosophila Proteins; D051034:Inhibitor of Apoptosis Proteins; D011956:Receptors, Cell Surface; C405956:gustatory receptor, Drosophila; D014199:Trehalose
keywords: Hemolymph; Insulin-like peptide signaling.; Life-span regulation; Sensory perception; Taste; Trehalose