Korean Journal of Microbiology (미생물학회지)

The Microbiological Society of Korea (한국미생물학회)
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Structural and Functional Analysis of a Forkhead Gene, fkhF, in a Filamentous Fungus Aspergillus nidulans

사상성 진균 Aspergillus nidulans에서 forkhead 유전자인 fkhF의 구조와 기능 분석

  • Park, Mi-Hye (Department of Pharmaceutical Engineering, Woosuk University) ;
  • Kim, Hyoun-Young (Department of Pharmaceutical Engineering, Woosuk University) ;
  • Kim, Jong-Hwa (Department of Pharmaceutical Engineering, Woosuk University) ;
  • Han, Kap-Hoon (Department of Pharmaceutical Engineering, Woosuk University)
  • 박미혜 (우석대학교 보건복지대학 제약공학과) ;
  • 김현영 (우석대학교 보건복지대학 제약공학과) ;
  • 김종화 (우석대학교 보건복지대학 제약공학과) ;
  • 한갑훈 (우석대학교 보건복지대학 제약공학과)
  • Received : 2009.12.09
  • Accepted : 2009.12.21
  • Published : 2009.12.31
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Abstract

Genome analysis of a model filamentous fungus, Aspergillus nidulans, revealed that there are six putative forkhead genes. Among them, fkhF (AN8949.2) showed A. nidulans-specific. fkhF gene is located in chromosome VII and composed of 2,337 bp coding region for 778 amino acid. Since little is known about the involvement of the forkhead proteins in the developmental process of the filamentous fungi, including A. nidulans, we generated a deletion mutant of fkhF gene and analyzed. Deletion of fkhF resulted in less-dense conidiophore formation in a solid culture. However, the sexual developmental process or cleistothecia formation was normal. Furthermore, fkhF deletion mutant produced conidiophores and conidia under the submerged culture, suggesting that the fkhF gene is involved in repression of inappropriated induction and maturation of asexual developmental process but not in sexual development.

사상성 모델 진균인 Aspergillus nidulans에 존재하는 forkhead 유전자들의 구조와 기능을 체계적으로 연구하기 위해 유전체 분석을 통해 forkhead 도메인을 가지고 있는 6개의 forkhead 유전자를 발견하였다. 이들 중 4개의 유전자들은 다른 진균에서 발견되는 forkhead 유전자들과 전반적인 유사성이 있었으나, 2개의 유전자들은 다른 종에서는 보존되어있지 않은 A. nidulans 특이적인 유전자들이었다. A. nidulans 특이적 forkhead 유전자들 중 하나인 fkhF(AN8949.2) 유전자는 염색체 7번에 위치하고 있고, ORF는 2,337 bp로 구성되어 있으며 778개의 아미노산을 암호화하고 있는 것으로 추정되었다. 예상되는 FkhF 단백질의 N-말단 부위에 보존된 forkhead 도메인을 가지고 있었으며, 이 유전자의 기능을 분석하기 위해 유전자제거 돌연변이 균주를 제조하였다. fkhF 유전자 결손돌연변이주는 유성분화 유도 조건 등을 포함한 여러 고체배지 배양 조건에서 유성분화에는 영향을 미치지 않았으나 무성포자병(conidiophore)의 생성 밀도와 성숙도에 영향을 주는 것으로 관찰되었고, 야생형과 달리 진탕배양시에 무성포자병을 형성함이 관찰되었다. 이는 fkhF 유전자가 A. nidulans의 부적절한 무성분화를 억제하고 정상적인 무성포자 성숙과정에 관여하는 유전자라는 것을 보여준다.

Keywords

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