ASNA-1は,C. elegansと哺乳類の細胞におけるインスリン分泌を正に調節する
Gautam Kao1, Cecilia Nordenson, Maria Still
1Umeå Center for Molecular Pathogenesis, Umeå University, SE-901 87 Umeå, Sweden.
Cell
|February 10, 2007
まとめ
C. elegansでは,asna-1遺伝子が成長とインスリン分泌を調節する. asna-1 が欠けているワームは,豊富な食物であっても,逆転的に成長を止め,インスリンシグナル伝達のための保存されたメカニズムを明らかにします.
科学分野:
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
- エンドクリノロジー エンドクリノロジー
背景:
- C. elegansの幼虫は,飢えたとき,最初の幼虫段階 (L1) で成長を止めます.
- L1停止を制御するメカニズムは, dauer diapauseと比較して理解が少ない.
- 成長調節におけるasna-1遺伝子の役割はほとんど不明である.
研究 の 目的:
- C. elegansの成長と発達におけるasna-1遺伝子の機能を調査する.
- L1逮捕におけるasna-1の役割を決定するために.
- asna-1とインスリンシグナル伝達との関係を調査する.
主な方法:
- C. elegans.におけるasna-1機能喪失変異体の遺伝子解析.
- 成長停止フェノタイプの評価,様々な給食条件下.
- asna-1変異体および過剰発現株におけるインスリン分泌レベルの分析.
- 培養された臓β細胞におけるヒトASNA1発現と機能の調査.
主要な成果:
- asna-1変異体は,十分な食物さえも,リバーシブルなL1成長停止を示す.
- asna-1は成長を制御するために非自律的に機能します.
- asna-1は,感覚神経細胞とインスリンを産生する腸内細胞で発現する.
- asna-1変異体はインスリン分泌量が低下し,過剰発現はインスリン効果を模倣する.
- 人間のASNA1は臓のβ細胞で特異的に発現し,インスリン分泌を調節する.
結論:
- asna-1は,C. elegans.におけるL1停止の重要な調節体である.
- ASNA1は,種間におけるインスリンシグナル伝達の保存された調節剤として作用する.
- この発見は,成長と代謝調節に影響を与える新しい経路を強調しています.
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