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Updated: Mar 19, 2026

Expression of Fluorescent Proteins in Branchiostoma lanceolatum by mRNA Injection into Unfertilized Oocytes
Published on: January 12, 2015
Hemichordate models
1Marine Biological Laboratory, Graduate School of Science, Hiroshima University, 2445 Mukaishima, Onomichi, Hiroshima 722-0073, Japan.
Abstract:
Hemichordates are marine animals with two different lifestyles. The solitary, free-living enteropneusts or acorn worms resemble polychaetes or earthworms, while the tiny, colonial, sessile pterobranchs are similar to bryozoans and phoronids. Hemichordates, together with echinoderms, comprise the clade Ambulacraria and are a sister group to the Chordata. As adults, they exhibit cardinal chordate characters, such as gill slits. Their embryogenesis and dipleurula-type (tornaria) larvae are very similar to those of echinoderms. Recent advances in comparative genomics and molecular developmental biology of hemichordates, especially the vermiform enteropneusts, have shed light on deuterostome ancestors. This paper briefly reviews the numerous recent studies on the Phylum Hemichordata.
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