title: Select microRNAs are essential for early development in the sea urchin.
abstract: microRNAs (miRNAs) are small noncoding RNAs that mediate post-transcriptional gene regulation and have emerged as essential regulators of many developmental events. The transcriptional network during early embryogenesis of the purple sea urchin, Strongylocentrotus purpuratus, is well described and can serve as an excellent model to test functional contributions of miRNAs in embryogenesis. We examined the loss of function phenotypes of major components of the miRNA biogenesis pathway. Inhibition of de novo synthesis of Drosha and Dicer in the embryo led to consistent developmental defects, a failure to gastrulate, and embryonic lethality, including changes in the steady state levels of transcription factors and signaling molecules involved in germ layer specification. We annotated and profiled small RNA expression from the ovary and several early embryonic stages by deep sequencing followed by computational analysis. miRNAs as well as a large population of putative piRNAs (piwi-interacting RNAs) had dynamic accumulation profiles through early development. Defects in morphogenesis caused by loss of Drosha could be rescued with four miRNAs. Taken together our results indicate that post-transcriptional gene regulation directed by miRNAs is functionally important for early embryogenesis and is an integral part of the early embryonic gene regulatory network in S. purpuratus.
authors.affiliation: Department of Molecular Biology, Cellular Biology and Biochemistry, Brown University, Providence, RI 02912, USA. jsong@udel.edu
authors.forename: Jia L
authors.initials: JL
authors.lastname: Song
authors.forename: Marlon
authors.initials: M
authors.lastname: Stoeckius
authors.forename: Jonas
authors.initials: J
authors.lastname: Maaskola
authors.forename: Marc
authors.initials: M
authors.lastname: Friedländer
authors.forename: Nadezda
authors.initials: N
authors.lastname: Stepicheva
authors.forename: Celina
authors.initials: C
authors.lastname: Juliano
authors.forename: Svetlana
authors.initials: S
authors.lastname: Lebedeva
authors.forename: William
authors.initials: W
authors.lastname: Thompson
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Rajewsky
authors.forename: Gary M
authors.initials: GM
authors.lastname: Wessel
mesh_terms: D000818:Animals; D053898:Biosynthetic Pathways / Q000235:genetics; D015152:Blotting, Northern; D015153:Blotting, Western; D016000:Cluster Analysis; D019295:Computational Biology; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000235:genetics* / Q000502:physiology; D055785:Gene Knockdown Techniques; D053263:Gene Regulatory Networks / Q000235:genetics*; D035683:MicroRNAs / Q000096:biosynthesis / Q000378:metabolism*; D058977:Molecular Sequence Annotation; D016376:Oligonucleotides, Antisense / Q000235:genetics; D010053:Ovary / Q000378:metabolism; D010641:Phenotype; D034741:RNA, Small Interfering / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D043244:Ribonuclease III / Q000172:deficiency / Q000235:genetics; D017422:Sequence Analysis, DNA; D047270:Strongylocentrotus purpuratus / Q000196:embryology* / Q000235:genetics*
chemical_list: D035683:MicroRNAs; D016376:Oligonucleotides, Antisense; D034741:RNA, Small Interfering; D043244:Ribonuclease III