title: Regulatory gene networks that shape the development of adaptive phenotypic plasticity in a cichlid fish.
abstract: Phenotypic plasticity is the ability of organisms with a given genotype to develop different phenotypes according to environmental stimuli, resulting in individuals that are better adapted to local conditions. In spite of their ecological importance, the developmental regulatory networks underlying plastic phenotypes often remain uncharacterized. We examined the regulatory basis of diet-induced plasticity in the lower pharyngeal jaw (LPJ) of the cichlid fish Astatoreochromis alluaudi, a model species in the study of adaptive plasticity. Through raising juvenile A. alluaudi on either a hard or soft diet (hard-shelled or pulverized snails) for between 1 and 8 months, we gained insight into the temporal regulation of 19 previously identified candidate genes during the early stages of plasticity development. Plasticity in LPJ morphology was first detected between 3 and 5 months of diet treatment. The candidate genes, belonging to various functional categories, displayed dynamic expression patterns that consistently preceded the onset of morphological divergence and putatively contribute to the initiation of the plastic phenotypes. Within functional categories, we observed striking co-expression, and transcription factor binding site analysis was used to examine the prospective basis of their coregulation. We propose a regulatory network of LPJ plasticity in cichlids, presenting evidence for regulatory crosstalk between bone and muscle tissues, which putatively facilitates the development of this highly integrated trait. Through incorporating a developmental time-course into a phenotypic plasticity study, we have identified an interconnected, environmentally responsive regulatory network that shapes the development of plasticity in a key innovation of East African cichlids.
authors.affiliation: Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Universitätstrasse 10, 78457, Konstanz, Germany; International Max Planck Research School for Organismal Biology, University of Konstanz, Universitätsstr 10, 78457, Konstanz, Germany.
authors.forename: Ralf F
authors.initials: RF
authors.lastname: Schneider
authors.forename: Yuanhao
authors.initials: Y
authors.lastname: Li
authors.forename: Axel
authors.initials: A
authors.lastname: Meyer
authors.forename: Helen M
authors.initials: HM
authors.lastname: Gunter
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000818:Animals; D001665:Binding Sites; D023681:Cichlids / Q000235:genetics*; D004032:Diet; D018507:Gene Expression Regulation, Developmental; D053263:Gene Regulatory Networks; D007568:Jaw / Q000033:anatomy & histology; D010641:Phenotype; D014157:Transcription Factors / Q000235:genetics
chemical_list: D014157:Transcription Factors
keywords: Astatoreochromis alluaudi; bone remodelling; cichlid; developmental time-course; evo-devo; pharyngeal jaw