Journal of Plant Biotechnology

  • 제41권1호
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  • Pages.10-18
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  • 2014
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  • 1229-2818(pISSN)
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  • 2384-1397(eISSN)
한국식물생명공학회 (The Korean Society of Plant Biotechnology)
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식물 종자지방 합성대사 연구의 최근 동향

Current research on seed oil biosynthesis

  • 김현욱 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 이경렬 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 김은하 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 정수진 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 노경희 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 강한철 (농촌진흥청, 국립농업과학원, 농업생명자원부) ;
  • 김종범 (농촌진흥청, 국립농업과학원, 농업생명자원부)
  • Kim, Hyun Uk (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Lee, Kyeong-Ryeol (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Kim, Eun Ha (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Jung, Su-Jin (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Roh, Kyung Hee (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Kang, Han Chul (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration) ;
  • Kim, Jong-Bum (Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration)
  • 투고 : 2014.02.04
  • 심사 : 2014.03.26
  • 발행 : 2014.03.31
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⟨ 이전 논문 다음 논문 ⟩

초록

식물지방은 인간의 필수지방산과 영양 공급원 이외에 산업원료와 바이오 연료로 사용되고 있다. 식물지방은 색소체에서 지방산이 합성되어 소포체로 이동되어 최종적으로 중성지방으로 합성 축적되는 복잡한 대사과정을 거친다. 최근 연구결과에 의하면 종자지방 합성에 있어서 기존에 알려진 케네디 경로 이외에 세포막의 주요 인지질인 PC가 종자지방 합성에 있어 중요한 역할을 하며 종자지방에 존재하는 지방산의 불포화도를 조절하는데 핵심 역할을 함이 밝혀졌다. 또한 색소체로부터 소포체로의 지방산 이동에 PC가 직접적인 운반체 역할을 할 가능성이 제시되고 있다. PC가 종자지방 합성에 중요한 역할을 한다는 결과는 앞으로 PC가 어떤 기작에 의해 지방산을 종자로 이동시키며 소포체의 어느 특정부위에서 지방을 합성하는지에 대한 연구가 이루어져야 한다.

Seed oils (triacylglycerols) of plants are used as a source of essential fatty acids and nutrition for human. In addition, triacylglycerols have been used as industrial raw materials and biofuels. Triacylglycerols are mainly accumulated in seeds by complicated biochemical pathways. Fatty acids are synthesized in the plastids and transported into the endoplasmic reticulum for synthesizing triacylglycerols. It is known for a long time that biosynthesis of triacylglycerols is performed by a de novo synthesis, the Kennedy pathway. However recent studies have revealed that phosphatidylcholine, a major component of cell membrane, plays a central role for triacylglycerols biosynthesis. Phosphatidylcholine is a key regulator determining the relative proportions of unsaturated fatty acids in seeds. It may be a major carrier for the fluxes of fatty acids from the plastid to the endoplasmic reticulum. This finding further suggests that studies of the functions of enzymes involved in the fluxes of fatty acids from phosphatidylcholine to triacylglycerols elucidate the specialized subdomains in the endoplasmic reticulum for triacylglycerols biosynthesis.

키워드

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