Hemichordate genomes and deuterostome origins.

TitleHemichordate genomes and deuterostome origins.
Publication TypeJournal Article
Year of Publication2015
AuthorsSimakov, O, Kawashima, T, Marlétaz, F, Jenkins, J, Koyanagi, R, Mitros, T, Hisata, K, Bredeson, J, Shoguchi, E, Gyoja, F, Yue, J-X, Chen, Y-C, Freeman, RM, Sasaki, A, Hikosaka-Katayama, T, Sato, A, Fujie, M, Baughman, KW, Levine, J, Gonzalez, P, Cameron, C, Fritzenwanker, JH, Pani, AM, Goto, H, Kanda, M, Arakaki, N, Yamasaki, S, Qu, J, Cree, A, Ding, Y, Dinh, HH, Dugan, S, Holder, M, Jhangiani, SN, Kovar, CL, Lee, SL, Lewis, LR, Morton, D, Nazareth, LV, Okwuonu, G, Santibanez, J, Chen, R, Richards, S, Muzny, DM, Gillis, A, Peshkin, L, Wu, M, Humphreys, T, Su, Y-H, Putnam, NH, Schmutz, J, Fujiyama, A, Yu, J-K, Tagawa, K, Worley, KC, Gibbs, RA, Kirschner, MW, Lowe, CJ, Satoh, N, Rokhsar, DS, Gerhart, J
Date Published2015 Nov 26
KeywordsAnimals, Chordata, Nonvertebrate, Conserved Sequence, Echinodermata, Evolution, Molecular, Genome, Multigene Family, Phylogeny, Signal Transduction, Synteny, Transforming Growth Factor beta

Acorn worms, also known as enteropneust (literally, 'gut-breathing') hemichordates, are marine invertebrates that share features with echinoderms and chordates. Together, these three phyla comprise the deuterostomes. Here we report the draft genome sequences of two acorn worms, Saccoglossus kowalevskii and Ptychodera flava. By comparing them with diverse bilaterian genomes, we identify shared traits that were probably inherited from the last common deuterostome ancestor, and then explore evolutionary trajectories leading from this ancestor to hemichordates, echinoderms and chordates. The hemichordate genomes exhibit extensive conserved synteny with amphioxus and other bilaterians, and deeply conserved non-coding sequences that are candidates for conserved gene-regulatory elements. Notably, hemichordates possess a deuterostome-specific genomic cluster of four ordered transcription factor genes, the expression of which is associated with the development of pharyngeal 'gill' slits, the foremost morphological innovation of early deuterostomes, and is probably central to their filter-feeding lifestyle. Comparative analysis reveals numerous deuterostome-specific gene novelties, including genes found in deuterostomes and marine microbes, but not other animals. The putative functions of these genes can be linked to physiological, metabolic and developmental specializations of the filter-feeding ancestor.

Alternate JournalNature
PubMed ID26580012
PubMed Central IDPMC4729200
Grant ListHD37277 / HD / NICHD NIH HHS / United States
R01 HD042724 / HD / NICHD NIH HHS / United States
U54 HG003273 / HG / NHGRI NIH HHS / United States
T32 HD055164 / HD / NICHD NIH HHS / United States
R01 HD037277 / HD / NICHD NIH HHS / United States
R01 HD073104 / HD / NICHD NIH HHS / United States
HD42724 / HD / NICHD NIH HHS / United States
R01HD073104 / HD / NICHD NIH HHS / United States