Expression and characterization of a lipase-related protein in the malpighian tubules of the Chinese oak silkworm, Antheraea pernyi.
Lipases are ubiquitous enzymes in nature, which play a crucial role in fat metabolism by catalyzing the hydrolysis of triacylglycerol to free fatty acids and glycerol. However, reports concerning insect lipase are rare. In this study, we studied the expression and activity of a lipase-related protein from Antheraea pernyi (ApLRP). Recombinant ApLRP was expressed in Escherichia coli cells and used to raise rabbit anti-ApLRP polyclonal antibodies. ApLRP mRNA and protein expression were abundant in the midgut and malpighian tubules, respectively. After challenge with four different microorganisms (E. coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus), the expression levels of ApLRP mRNA in midgut were inducted significantly compared with the control. The different pathogens induced different ApLRP gene expression patterns. The optimum temperature and pH for the enzyme's activity were 35°C and 7.0, respectively. ApLRP activity was stimulated in the presence of Mg2+, Na+, Ca2+ and b-mercaptoethanol; while Zn2+, Cu2+ and Fe3+ inhibited its activity. Detergents such as SDS, glycerol and Tween-20 increased the lipase activity by 20-30%. Our results indicated that ApLRP might play an important role in the innate immunity of insects.
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
L
L
Wang
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
J
J
Li
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
X
X
Zhao
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
C
C
Qian
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
G
G
Wei
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
B
B
Zhu
College of Life Science, Anhui Agricultural University,Hefei 230036,China.
C
C
Liu
D000818:Animals; D052982:Beauveria / Q000502:physiology; D012831:Bombyx / Q000201:enzymology* / Q000276:immunology / Q000382:microbiology; D002118:Calcium / Q000494:pharmacology; D003300:Copper / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D004926:Escherichia coli / Q000502:physiology; D054884:Host-Pathogen Interactions; D006863:Hydrogen-Ion Concentration; D007113:Immunity, Innate / Q000187:drug effects; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000494:pharmacology; D007814:Larva / Q000201:enzymology / Q000276:immunology / Q000382:microbiology; D008049:Lipase / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D008274:Magnesium / Q000494:pharmacology; D008317:Malpighian Tubules / Q000378:metabolism*; D016982:Micrococcus luteus / Q000502:physiology; D017924:Nucleopolyhedroviruses / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology; D013696:Temperature; D015032:Zinc / Q000494:pharmacology
D019476:Insect Proteins; D012333:RNA, Messenger; D003300:Copper; D012964:Sodium; D007501:Iron; D008049:Lipase; D008274:Magnesium; D015032:Zinc; D002118:Calcium
Antheraea pernyi; activity; immunity; lipase