• 식물조직배양학회지
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• 제24권2호
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• pp.93-97
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• 1997

Linoleic acid를 linolenic acid로 전환시키는 지방산불포화효소의 유전자(fad3)를 유채의 fad3 DNA probe를 이용한 plaque hybridization방법으로 $\lambda$ZAPII Arabidopsis thaliana cDNA expression library로부터 분리하였으며 1.8 kb-EcoRI DNA조각을 지니는 lambda clone을 pGEM7으로 subcloning하여 염기서열을 분석하였다. 그 결과로부터의 아미노산서열분석에 의하면 fad3 유전자는 open reading frame이 386개의 아미노산으로 이루어졌으며 44,075 Da의 분자량이 예측되고 있다. 엽록체의 $\omega$-3 지방산불포화효소(fad7)와 endoplasmic reticulum의 지방산불포화효소(fad2)와의 비교시 각각 70%와 58%의 유사성이 나타났다. 특히 82-151의 아미노산서열과 276-333의 아미노산지역은 보존성이 높았으며 이는 불포화지방산효소의 기능에 필수적인 지역으로 보여진다. 한편 대장균을 이용한 IPTG에 의한 Fad3단백질의 유도생성은 대장균의 생육에 독성효과를 나타내는 것으로 나타났다.

• Journal of Plant Biotechnology
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• 제1권1호
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• pp.20-30
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• 1999

In order to modify lipid production of Perilla qualitatively as well as quantitatively by genetic engineering, genes involved in carbon metabolism were isolated and characterized. These include acyl-ACP thioesterases from Perilla frutescens and Iris sp., four different $\beta$-ketoacyl- ACP synthases from Perilla frutescens, and two $\Delta$15 a-cyl-ACP desaturases(Pffad7, pffad3). Δ15 acyl-ACP desa turase (Δ15-DES) is responsible for the conversion of linoleic acid (18:2) to $\alpha$-linolenic acid (ALA, 18:3). pffad 3 encodes Δ15 acyl-desaturase which is localized in ER membrane. On the other hand, Pffad7 encodes a 50 kD plastid protein (438 residues), which showed highest sequence similarity to Sesamum indicum fad7 protein. Northern blot analysis revealed that the Pffad7 is highly expressed in leaves but not in roots and seeds. And Pffad3 is expressed throughout the seed developmental stage except very early and fully mature stage. We constructed Pffad7 gene under 355 promoter and Pffad3 gene under seed specific vicillin promoter. Using Pffad7 construct, Perilla, an oil seed crop in Korea, was transformed by Agrobacterium leaf disc method. $\alpha$-linolenic acid contents increased in leaves but decreased in seeds of transgenic Perilla. Currently, we are transforming Perilla with Pffad3 construct to change Perilla seed oil composition. We isolated three ADP-glucose pyrophosphorylase (AGP) genes from Perilla immature seed specific cDNA library. Nucleotide sequence analysis showed that two of three AGP (Psagpl, Psagp2) genes encode AGP small subunit polypeptides and the remaining (Plagp) encodes an AGP large subunit. PSAGPs, AGP small subunit peptide, form active heterotetramers with potato AGP large subunit in E. coli expressing plant AGP genes.