脊椎動物の脳内の脊椎動物型のオプシンを持つ状光受容体
Detlev Arendt1, Kristin Tessmar-Raible, Heidi Snyman
1Developmental Biology Department, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69012 Heidelberg, Germany. detlev.arendt@embl.de
まとめ
昆虫と脊椎動物の目は,異なる光受容体細胞を使用しています. 海洋のラップワームプラティネリスは両方のタイプを有しており,初期の祖先で共存していたことを示唆し,脊椎動物の眼の進化の洞察を提供している.
科学分野:
- 進化生物学の進化生物学について
- 神経科学は神経科学である.
- オフタルモロジック (眼科)
背景:
- 視力は異なる光受容体細胞に依存する:昆虫のラブドメリック細胞,脊椎動物のシルリアン細胞.
- これらの細胞タイプは,異なる構造と光を伝達するメカニズムを示しています.
研究 の 目的:
- 海洋ラグワームプラティネリス (Platynereis) の光受容体細胞タイプの存在と進化的起源を調査する.
- プラティネリスの光受容体を昆虫や脊椎動物の光受容体と比較して,眼の初期進化を理解する.
主な方法:
- 光受容体細胞タイプとオプシンの比較分析.
- プラティネレスにおける光受容体のヒストロロジカルおよび分子特性.
主要な成果:
- Platynereisは,眼にあるラブドメリック光受容体細胞と,脳にあるシリアリ光受容体細胞の両方を所有しています.
- プラティネリスのシリア光受容体は,脊椎動物のオプシンに関連した光色素を使用します.
- 異なるオプシンを持つ両方の光受容体タイプは,最後の共通の祖先であるウルビラテリアに存在していた可能性が高い.
結論:
- この発見は,双子体におけるラボドメリック光受容体とシリアリ光受容体の共通の進化的遺産を示唆している.
- この研究は,脊椎動物の目の進化軌跡に関する新しい洞察を提供します.
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