let-60は,C. elegans vulval誘導中に細胞運命を指定する遺伝子で,rasタンパク質をコードしています

M Han¹, P W Sternberg

¹Howard Hughes Medical Institute.

Cell

|November 30, 1990

まとめ

C. elegans の let-60 遺伝子は,ヴァルバの発達に不可欠な ras 遺伝子です. その正確な発現は細胞運命を制御し,活動が増加し,ヴァルバ誘導における上流遺伝子をバイパスする.

科学分野:

発達生物学発達生物学について
分子遺伝学分子遺伝学
細胞生物学細胞生物学

背景:

C. elegans の let-60 遺伝子は,以前は,ヴァルバ誘導中の細胞運命を決定する制御に関与していた.
ヴァルヴァ発達の分子メカニズムを理解することは,より広範な発達過程を理解するために不可欠です.

研究の目的:

let-60遺伝子をクローンし,特徴づけること.
ヴァルバ細胞の運命決定と誘導経路におけるlet-60遺伝子産物の役割を明らかにする.

主な方法:

遺伝子クローニングとlet-60遺伝子の配列決定.
既知のrasタンパク質とのlet-60遺伝子製品ホモロジーの分析.
染色体外配列とC. elegans. の遺伝子変異を用いた機能分析.

主要な成果:

let-60遺伝子は,ras遺伝子製品と高度に保存されたタンパク質をコードし,共有された生化学的機能を示唆しています.
変化したレット-60ラスの活動 (機能の獲得または機能の喪失) は,ヴァルバ発達の逆のフェノタイプにつながります.
let-60 rasの活性が増加すると,他のヴァルバ誘導遺伝子の変異によって引き起こされる欠陥を抑制することができます.

結論:

let-60遺伝子産物は,C. elegansのrasタンパク質で, Vulvalの適切な発達に不可欠である.
let-60 ras発現のレベルと空間的なパターンは,ヴァルバインダクション中に厳格に規制されています.
異常なlet-60 rasの活動は,ヴァルバ誘導経路におけるその中心的な役割を強調し,上流信号要求を回避する可能性がある.

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