BRAIN and NERVE－神経研究の進歩60巻4号

2008年04月発行

増大特集 神経系の発生とその異常

脳発生におけるPax6の機能とその異常

著者： 松本葉子¹² 大隅典子¹

所属機関： ¹東北大学大学院医学系研究科創生応用医学研究センター形態形成解析分野 ²東北大学医学部小児病態学分野

ページ範囲：P.365 - P.374

文献概要

はじめに

　ヒトの脳には100～200億のニューロン（神経細胞）が存在し，その約10倍の数のグリア細胞（神経膠細胞）がニューロンの働きを助けていると考えられている。脳の中でニューロンは精緻な神経回路を形成し，高次機能を発揮している。

　近年の分子発生学・分子遺伝学の進歩により，中枢神経系の発生を制御する分子メカニズムが明らかになり，さまざまな異常についてその責任遺伝子が同定されてきた。転写因子をコードするPax6遺伝子は，眼の形成に関するマスターコントロール遺伝子として発見され，その後の研究から神経管の領域化やニューロン新生，ニューロンの移動，神経軸索の伸長などさまざまな現象に関与していることが明らかになっている。本稿では中枢神経系の初期発生について概説し，胎生期におけるPax6の機能について解説する。最後に，生後のPax6研究の最近の知見について紹介する。

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