c-Junは自身とc-Fosで二重化し,異なるDNA結合親和性の複合体を形成する

T D Halazonetis¹, K Georgopoulos, M E Greenberg

¹Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.

Cell

|December 2, 1988

まとめ

プロトオンコゲンであるc-Junとc-Fosは,転写因子複合体を形成する. このc-Jun/c-Fosヘテロジマーは,c-Junホモジマよりも25倍効率的にDNAを結合し,遺伝子発現を調節する.

科学分野:

分子生物学は分子生物学である.
遺伝学遺伝学とは
細胞生物学細胞生物学

背景:

プロトオンコゲンであるc-Junとc-Fosは,転写を調節するタンパク質をコードする.
これらのタンパク質は,プロモーターのAP-1活性化要素と結合する複合体を形成します.

研究の目的:

c-Junホモジメとc-Jun/c-FosヘテロジメのDNA結合親和性を調査する.
c-Fosがc-JunのDNA結合活性を調節する役割を解明する.

主な方法:

c-Junとc-Fosタンパク質のインビトロ翻訳.
AP-1 DNAサイトへのホモジメロおよびヘテロジメロ複合体のDNA結合活性分析.

主要な成果:

c-Junタンパク質は,AP-1DNAサイトをホモジマーとして結合する.
c-Fosタンパク質はDNAを独立して二酸化したり結合したりしません.
コトランスレートされたc-Junとc-Fosタンパク質は,c-Junホモダイマーと比較して,AP-1サイトに対する親和性が25倍増加したヘテロダイマーを形成する.

結論:

c-Fosは,成長因子刺激細胞で転写活性複合体を形成するc-Junの自然なパートナーです.
c-Fosなしのc-Junの過剰発現は,異常なホモディメア複合体につながり,正常な遺伝子調節を妨害する可能性があります.

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