title: Developmental Progression in the Coral Acropora digitifera Is Controlled by Differential Expression of Distinct Regulatory Gene Networks.
abstract: Corals belong to the most basal class of the Phylum Cnidaria, which is considered the sister group of bilaterian animals, and thus have become an emerging model to study the evolution of developmental mechanisms. Although cell renewal, differentiation, and maintenance of pluripotency are cellular events shared by multicellular animals, the cellular basis of these fundamental biological processes are still poorly understood. To understand how changes in gene expression regulate morphogenetic transitions at the base of the eumetazoa, we performed quantitative RNA-seq analysis duringAcropora digitifera's development. We collected embryonic, larval, and adult samples to characterize stage-specific transcription profiles, as well as broad expression patterns. Transcription profiles reconstructed development revealing two main expression clusters. The first cluster grouped blastula and gastrula and the second grouped subsequent developmental time points. Consistently, we observed clear differences in gene expression between early and late developmental transitions, with higher numbers of differentially expressed genes and fold changes around gastrulation. Furthermore, we identified three coexpression clusters that represented discrete gene expression patterns. During early transitions, transcriptional networks seemed to regulate cellular fate and morphogenesis of the larval body. In late transitions, these networks seemed to play important roles preparing planulae for switch in lifestyle and regulation of adult processes. Although developmental progression inA. digitiferais regulated to some extent by differential coexpression of well-defined gene networks, stage-specific transcription profiles appear to be independent entities. While negative regulation of transcription is predominant in early development, cell differentiation was upregulated in larval and adult stages.
authors.affiliation: Okinawa Institute of Science and Technology, Okinawa, Japan School of Natural Sciences, Ryukyus University, Okinawa, Japan argalaxin@gmail.com alexander.mikheyev@oist.jp.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Reyes-Bermudez
authors.affiliation: Okinawa Institute of Science and Technology, Okinawa, Japan.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Villar-Briones
authors.affiliation: Universidad de los Andes, Bogota, Colombia.
authors.forename: Catalina
authors.initials: C
authors.lastname: Ramirez-Portilla
authors.affiliation: School of Natural Sciences, Ryukyus University, Okinawa, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Hidaka
authors.affiliation: Okinawa Institute of Science and Technology, Okinawa, Japan argalaxin@gmail.com alexander.mikheyev@oist.jp.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Mikheyev
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000235:genetics* / Q000254:growth & development; D002454:Cell Differentiation / Q000235:genetics; D019143:Evolution, Molecular; D018507:Gene Expression Regulation, Developmental; D053263:Gene Regulatory Networks / Q000235:genetics*; D007814:Larva / Q000235:genetics* / Q000254:growth & development; D059467:Transcriptome / Q000235:genetics*
keywords: RNA-seq; WGCNA; cell differentiation; coral development; tissue morphogenesis; transcription regulation