title: Exploring new molecules and activities from Lonomia obliqua caterpillars.
abstract: Skin contact with Lonomia caterpillar bristles causes a consumptive coagulopathy. From a cDNA library we cloned and expressed a prothrombin activator (rLopap) in active form, and from the bristles extract we characterized a FX activator (Losac). Several clones were sequenced and analyzed by expressed sequence tags. A database of about 1,270 sequences was constructed and deposited in NCBI (CX815710-CX817210) [corrected] Both the native protein from the venom (Lopap) and the recombinant form (r-Lopap) promoted prothrombin hydrolysis, generating prethrombin-2, F1.2 and thrombin. Losac is a single-chain (43 kDa) protein that cleaves the FX heavy chain producing FXaalpha. In HUVECs rLopap and Losac are able to modulate cell survival by preventing apoptosis. rLopap increases NO and PGI2 concentration and Losac induces t-PA expression. Finally, to identify the venom proteins related to human envenomation, a 2D electrophoresis map is being performed as an attempt to find the major toxins recognized by the anti-lonomia venom.
authors.affiliation: Biochemistry and Biophysics Laboratory, Butantan Institute, São Paulo, Brazil. amchudzinski@butantan.gov.br
authors.forename: Ana Marisa
authors.initials: AM
authors.lastname: Chudzinski-Tavassi
authors.forename: Miryam Paola
authors.initials: MP
authors.lastname: Alvarez Flores
mesh_terms: D000818:Animals; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D004211:Disseminated Intravascular Coagulation / Q000139:chemically induced; D015723:Gene Library; D006801:Humans; D007814:Larva / Q000472:pathogenicity; D007915:Lepidoptera / Q000472:pathogenicity*; D009363:Neoplasm Proteins / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D017422:Sequence Analysis, DNA; D012697:Serine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D009363:Neoplasm Proteins; C119835:Lonomia obliqua prothrombin activator protease; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases; C030910:cancer procoagulant