Chudzinski-Tavassi Ana Marisa, Alvarez Flores Miryam Paola
Biochemistry and Biophysics Laboratory, Butantan Institute, São Paulo, Brazil.
Pathophysiol Haemost Thromb. 2005;34(4-5):228-33. doi: 10.1159/000092429.
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.
皮肤接触洛诺米毛虫刚毛会引发消耗性凝血病。我们从一个cDNA文库中克隆并表达了具有活性形式的凝血酶原激活剂（rLopap），并从刚毛提取物中鉴定出一种FX激活剂（Losac）。对几个克隆进行了测序，并通过表达序列标签进行分析。构建了一个约1270个序列的数据库并提交至NCBI（CX815710 - CX817210）[已修正]毒液中的天然蛋白（Lopap）和重组形式（r - Lopap）均能促进凝血酶原水解，生成凝血酶原2、F1.2和凝血酶。Losac是一种单链（43 kDa）蛋白，可切割FX重链产生FXaα。在人脐静脉内皮细胞（HUVECs）中，rLopap和Losac能够通过防止细胞凋亡来调节细胞存活。rLopap可增加一氧化氮（NO）和前列环素（PGI2）的浓度，Losac可诱导组织型纤溶酶原激活剂（t - PA）表达。最后，为了鉴定与人类中毒相关的毒液蛋白，正在进行二维电泳图谱分析，试图找出抗洛诺米毒液识别的主要毒素。
