タケウチ　マサキ   Takeuchi Masaki   竹内　雅貴    所属   川崎医療福祉大学  医療技術学部 臨床検査学科    職種   准教授
論文種別	原著
言語種別	英語
査読の有無	査読なし
表題	The Genus Polypterus (Bichirs): A Fish Group Diverged at the Stem of Ray-Finned Fishes (Actinopterygii)
掲載誌名	正式名：Cold Spring Harbor Protocols ISSNコード：19403402/15596095
巻・号・頁	2009(5)
著者・共著者	Takeuchi M, Okabe M, Aizawa S
発行年月	2009/05
概要	Axis and germ-layer formations are central issues in vertebrate embryology that can be examined in the zebrafish, Xenopus, chick, and mouse. An intriguing question is how the mechanisms that existed in an ancestral vertebrate have been modified during vertebrate evolution. A major stream of vertebrates (Osteichthyes) evolved in two monophyletic lineages: the Sarcopterygii and Actinopterygii. The zebrafish is a well-known and well-studied teleost fish highly derived in the actinopterygian lineage, ray-finned fishes. The early cleavage pattern of teleosts is meroblastic, in contrast to the holoblastic cleavage seen in amphibians, which diverged early in the sarcopterygian lineage. There are many differences in the molecular and cellular mechanisms of embryogenesis between teleosts and amphibians or actinopterygians and sarcopterygians, including the differences in bauplan (body plan). However, the lineage leading to the teleost fishes has undergone a whole-genome duplication before their radiation, which may have also caused changes in molecular usage independent of the teleost bauplan. Polypterus diverged from all other actinopterygians ~400 million years ago (Mya) during the Devonian period, soon after the divarication of an ancestral bony fish into Actinopterygii and Sarcopterygii. Polypterus is thus uniquely well suited for studies assessing the ancestral state or bauplan of Osteichthyes and Actinopterygii, as well as the divergence of embryogenetic processes in teleosts and amphibians.
DOI	doi:10.1101/pdb.emo117
文献番号	PMID: 20147149