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AMPK γ 유전자의 표피세포극성 유지기능 규명

AMPK γ is Required for Maintaining Epithelial Cell Structure and Polarity

  • 고형종 (동아대학교 의과대학 약리학교실)
  • Koh, Hyong-Jong (Department of Pharmacology, Mitochondria Hub Regulation Center (MHRC), Dong-A University College of Medicine)
  • 투고 : 2011.01.27
  • 심사 : 2011.02.09
  • 발행 : 2011.05.30

초록

AMPK는 catalytic ${\alpha}$ subunit과 regulatory ${\beta}$${\gamma}$ subunit으로 구성된 인산화 효소로, 그 동안 생체 내 중요 대사 조절자로써 연구되어 왔으나, 최근 유전학 연구를 통해 지금까지 밝혀지지 아니한 새로운 생체기능을 가짐이 밝혀졌다. 본 연구에서 초파리 유전학 기법을 활용하여 AMPK ${\gamma}$ subunit 유전자가 결손된 모델 초파리를 제작 하여 연구한 결과, AMPK ${\gamma}$ 유전자 결손 시 초파리 embryo의 표피형성이 심각하게 저해됨을 발견하였고, 조직학적 실험을 통해 표피세포의 극성이 AMPK ${\gamma}$ 유전자 결손 초파리에서 손상되어 있음을 확인하였다. 또한 세포극성을 조절하는 중요 분자인 MRLC의 인산화 또한 AMPK ${\gamma}$ 유전자 결손 시 저해되었으며, AMPK ${\gamma}$ 유전자 재도입 시 MRLC인산화와 표피세포의 극성이 모두 회복됨이 확인되어, 초파리 표피세포의 극성유지에 AMPK ${\gamma}$ 유전자가 필수적 임을 확인하였다.

AMP-activated protein kinase (AMPK), a heterotrimeric complex comprising a catalytic ${\alpha}$ subunit and regulatory ${\beta}$ and ${\gamma}$ subunits, has been primarily studied as a major metabolic regulator in various organisms, but recent genetic studies discover its novel physiological functions. The first animal model with no functional AMPK ${\gamma}$ subunit gene was generated by using Drosophila genetics. AMPK ${\gamma}$ flies demonstrated lethality with severe defects in cuticle formation. Further histological analysis found that deletion of AMPK ${\gamma}$ causes severe defects in cell polarity in embryo epithelia. The phosphorylation of nonmuscle myosin regulatory light chain (MRLC), a critical regulator of epithelial cell polarity, was also diminished in AMPK ${\gamma}$ embryo epithelia. These defects in AMPK ${\gamma}$ mutant epithelia were successfully restored by over-expression of AMPK ${\gamma}$. Collectively, these results suggested that AMPK ${\gamma}$ is a critical cell polarity regulator in metazoan development.

키워드

참고문헌

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