Open AccessG protein and diacylglycerol regulate metamorphosis of planktonic molluscan larvae
Author(s) -
Gregory T. Baxter,
Daniel E. Morse
Publication year - 1987
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.84.7.1867
Subject(s) - metamorphosis , diacylglycerol kinase , biology , second messenger system , g protein , cholera toxin , microbiology and biotechnology , gtp' , biochemistry , signal transduction , protein kinase c , larva , endocrinology , enzyme , ecology
The regulatory guanine nucleotide binding protein (G protein) activators cholera toxin and the GTP analog 5-guanylyl imidophosphate, the second messenger diacylglycerol, and certain diamino acids all facilitate (amplify) the settlement and metamorphic responses of planktonic larvae ofHaliotis rufescens (marine mollusc) to morphogenetic chemical stimuli. In contrast, the G protein-inhibiting analog guanosine 5′-O -[β-thio]diphosphate inhibits facilitation by L-α,β-diaminopropionic acid but does not block facilitation by diacylglycerol. Diacylglycerol, cholera toxin, and the guanine nucleotide analogs alone neither induce the settlement and metamorphosis of the larvae nor do they inhibit induction of metamorphosis by γ-aminobutyric acid. These results thus establish the existence of separate regulatory and inductive pathways controlling larval metamorphosis in response to two classes of exogenous chemical signals from the environment. The regulatory pathway, operating independently through a G protein-diacylglycerol cascade apparently controlled by facilitating diamino acids in the water column, can amplify the larval responsiveness to inducers of metamorphosis. This mechanism may have adaptive significance in the recognition and selection of favorable habitats for metamorphosis of the larvae. Similar regulatory pathways, based on exogenous control of a G protein-diacylglycerol cascade, may govern responsiveness to stimuli in other sensory and developmental systems.