Fatty Acid Composition of Different tissues of Spodoptera exigua Larvae and a Role of Cellular Phospholipase A2

파밤나방 유충의 조직별 지방산 구성과 세포성 인지질분해효소의 역할

  • Kim, Yonggyun (Department of Bioresource Sciences, Andong National University) ;
  • Lee, Seunghee (Department of Bioresource Sciences, Andong National University) ;
  • Seo, Seunghwan (Department of Bioresource Sciences, Andong National University) ;
  • Kim, Kunwoo (Department of Bioresource Sciences, Andong National University)
  • 김용균 (안동대학교 생명자원과학과) ;
  • 이승희 (안동대학교 생명자원과학과) ;
  • 서승환 (안동대학교 생명자원과학과) ;
  • 김건우 (안동대학교 생명자원과학과)
  • Received : 2016.03.03
  • Accepted : 2016.05.12
  • Published : 2016.06.01


Eicosanoids are a group of C20 oxygenated polyunsaturated fatty acids (PUFAs). To monitor biosynthetic precursors of these PUFAs, this study extracted fatty acids from different tissues of the beet armyworm, Spodoptera exigua, and assessed their compositions using GC/MS. Fifth instar larvae were dissected to isolate different tissues of gut, fat body, hemocytes, and integument. From each tissue, total lipids were extracted and fractionated into neutral lipid (NL), glycolipid (GL), and phospholipid (PL). Most tissues contained palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2), and linolenic acid (18:3). However, their compositions were different among tissues and lipid types. Fat body and hemocytes possessed other type of fatty acids such as myristic acid (14:0) and three unknown fatty acids. Among lipid types, PL contained relatively high levels of linolenic acid than NL and GL, while it had lower saturated fatty acids. Total unsaturated fatty acid composition was varied among tissues and lipid types. PL was rich in unsaturated fatty acids in fat body, gut, and hemocytes. There was a significant influence of calcium-independent phospholipase $A_2$ ($iPLA_2$) on maintaining fatty acid composition because RNA interference of $iPLA_2$ expression significantly modified fatty acid compositions in NL and PL. However, this study did not detect arachidonic acid, a main eicosanoid biosynthesis precursor, in all tissues. This suggests an alternative biosynthesis of eicosanoids in insects, which is distinct from the biosynthetic pathway of mammals.


Eicosanoid;Fatty acid;Phospholipase;Spodoptera exigua


Supported by : 농림수산식품기술평가원


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