Open AccessTranscriptomic analysis of sea star development through metamorphosis to the highly derived pentameral body plan with a focus on neural transcription factors
Author(s) -
Maria Byrne,
Demian Koop,
Dario Strbenac,
Paula Cisternas,
Regina Balogh,
Jean Yang,
Phillip L. Davidson,
Gregory A. Wray
Publication year - 2020
Publication title -
dna research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 98
eISSN - 1756-1663
pISSN - 1340-2838
DOI - 10.1093/dnares/dsaa007
Subject(s) - biology , body plan , metamorphosis , focus (optics) , transcriptome , transcription factor , neural development , transcription (linguistics) , computational biology , evolutionary biology , microbiology and biotechnology , genetics , gene , ecology , gene expression , larva , linguistics , physics , philosophy , optics
The Echinodermata is characterized by a secondarily evolved pentameral body plan. While the evolutionary origin of this body plan has been the subject of debate, the molecular mechanisms underlying its development are poorly understood. We assembled a de novo developmental transcriptome from the embryo through metamorphosis in the sea star Parvulastra exigua. We use the asteroid model as it represents the basal-type echinoderm body architecture. Global variation in gene expression distinguished the gastrula profile and showed that metamorphic and juvenile stages were more similar to each other than to the pre-metamorphic stages, pointing to the marked changes that occur during metamorphosis. Differential expression and gene ontology (GO) analyses revealed dynamic changes in gene expression throughout development and the transition to pentamery. Many GO terms enriched during late metamorphosis were related to neurogenesis and signalling. Neural transcription factor genes exhibited clusters with distinct expression patterns. A suite of these genes was up-regulated during metamorphosis (e.g. Pax6, Eya, Hey, NeuroD, FoxD, Mbx, and Otp). In situ hybridization showed expression of neural genes in the CNS and sensory structures. Our results provide a foundation to understand the metamorphic transition in echinoderms and the genes involved in development and evolution of pentamery.