CONCLUSION

1. Deprivation of amino acids induces IL6 mRNA in the presence of glucose in HeLa cells.

2. 3’UTR of IL6 is deeply implicated in this process.

3. Partially deleted 3’UTR also contributes to increase of reporter activities, suggesting that cis-acting elements within 3’UTR distribute extending whole IL6 3’UTR.

4. NF-κB knock-down partially blocks reporter activities containing 3’UTR of IL6 as well as IL6 mRNA induction, implying that NF-κB functions in 3’UTR of IL6, subsequently stabilization of mRNA stabilization in addition to activation of IL6 promoters.

5. The studies with MAP kinase inhibitors are showing that activity of p38 MAP kinase is required for mRNA stabilization of IL6 through 3’UTR, therefore, p38-MK2/3-TTP pathway would be associated with IL6 mRNA stabilization through ARE sequences within 3’UTR sequences.

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２７

양분 고갈 상태에서 IL6 mRNA의 안정성과 관련이 있고, 활성화 영향을 준다는 것을 제시한다.

결론적으로 이 연구는 NF-κB와 p38에 관한 stress signal은 3’UTR sequence를 통 해 mRNA 안정성에 관여하지만, 이것에 대한 분자적 구조에 대한 연구는 더 필 요 할 것이다.

핵심어 : IL6 cytokines, AU rich element, 3’untranslation region, post-transcription, mRNA stability and translation