Expression and regulation of phospholipase A2 in venom gland of the chinese honeybee, Apis cerana cerana.
Phospholipase A(2) (PLA(2)) is one of the components of bee venom with a wide range of pharmacological functions. It operates as a major allergen working with other venom components to defend the colony from intruder. In the present study, the cDNA sequence of the Ac-pla(2) gene from cDNA library of the venom gland of Apis cerana was compared with the amplified corresponding region of genomic DNA. The result showed that the Ac-pla(2) gene consisted of four exons and three introns. Southern blot showed that the Ac-pla(2) gene was a single copy per haploid genome. The most active transcription period was during the first 8 days of adults, which correspondingly was the period of sharp increase of PLA(2) protein. ELISA analysis revealed that the PLA(2) was undetectable in pupal stage and the newly eclosed adult, but increased sharply to a maximum of 10-12 mug per honeybee by 8-10 days of adult life, followed by a gradual decrease to 8 mug for the rest of adult life. Transcriptional or post transcriptional regulation is the key step for Ac-pla(2) expression. The early secreted Ac-PLA(2) showed a low degree of post-translational modification; with increasing age, glycosylation was detected by Western blot and glycoprotein staining analysis. Different post-translational modifications were found among different individuals in A. cerana when compared to A. mellifera.
Li
Jiang-Hong
JH
Institute of Applied Entomology, Zhejiang University, Hangzhou, China.
Zhang
Chuan-Xi
CX
Shen
Li-rong
LR
Tang
Zhen-Hua
ZH
Cheng
Jia-An
JA
D000367:Age Factors; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001514:Bee Venoms / Q000201:enzymology* / Q000235:genetics; D001516:Bees; D015139:Blotting, Southern; D015153:Blotting, Western; D002681:China; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D040461:Gene Components; D015971:Gene Expression Regulation, Enzymologic; D015723:Gene Library; D006023:Glycoproteins / Q000378:metabolism; D008969:Molecular Sequence Data; D010741:Phospholipases A / Q000235:genetics* / Q000378:metabolism*; D054467:Phospholipases A2; D017422:Sequence Analysis, DNA
D001514:Bee Venoms; D017931:DNA Primers; D018076:DNA, Complementary; D006023:Glycoproteins; D010741:Phospholipases A; D054467:Phospholipases A2