Molecular characterization of a new scorpion venom lipolysis activating peptide: Evidence for disulfide bridge-mediated functional switch of peptides.
Venoms from scorpions contain extremely rich bioactive peptides that often carry diverse functions and are presumably needed to achieve synergistic effects for rapidly immobilizing prey and defending themselves. BotLVP1 is a unique heterodimer protein recently found in the scorpion Buthus occitanus tunetanus venom that is structurally related to scorpion toxins affecting sodium channels (NaScTxs) but exhibits adipocyte lipolysis activity. We have isolated and identified two cDNA clones encoding subunits alpha and beta of a BotLVP1-like peptide (named BmLVP1) from the Chinese scorpion Buthus martensii venom gland and determined the first complete gene structure of this subfamily. These results highlight a genetic link between these lipolysis activating peptides and NaScTxs. Comparison of cDNA and genomic sequences combined with protein structural and functional analysis provides evidence supporting the existence of RNA editing mechanism in scorpion venom glands, which could mediate functional switch of BmLVP1 gene, from adipocyte lipolysis to neurotoxicity, by altering the wrapper disulfide bridge (WDB) pattern of the peptides.
Zhu
S
S
Group of Animal Innate Immunity, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, No. 25 Beisihuan-Xi Road, Beijing 100080, PR China. Zhusy@ioz.ac.cn
Gao
B
B
D000225:Adenine / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D004220:Disulfides / Q000378:metabolism*; D008066:Lipolysis; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D017393:RNA Editing / Q000235:genetics; D012604:Scorpion Venoms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012605:Scorpions / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism; D040681:Structural Homology, Protein; D014158:Transcription, Genetic / Q000235:genetics
D018076:DNA, Complementary; D004220:Disulfides; D010455:Peptides; D012604:Scorpion Venoms; D015222:Sodium Channels; D000225:Adenine