槲寄生凝集素在穿过膜进入细胞质之前会解离为催化亚基和结合亚基。

Mistletoe lectin dissociates into catalytic and binding subunits before translocation across the membrane to the cytoplasm.

作者信息

Agapov I I, Tonevitsky A G, Moysenovich M M, Maluchenko N V, Weyhenmeyer R, Kirpichnikov M P

机构信息

State Research Center GNIIgenetika, Moscow, Russia.

出版信息

FEBS Lett. 1999 Jun 11;452(3):211-4. doi: 10.1016/s0014-5793(99)00639-0.

DOI:10.1016/s0014-5793(99)00639-0

PMID:10386592

Abstract

Hybridomas producing monoclonal antibodies (mAbs) against the mistletoe lectin A-chain (MLA) were obtained to investigate the intracellular routing and translocation of ribosome-inactivating proteins. Anti-MLA mAb MNA5 did not bind the holotoxin but interacted with isolated MLA. This epitope was not recognized upon MLA denaturation or conjugation of MLA with the ricin binding subunit (RTB). Furthermore, the mAbs did not appreciably react with a panel of MLA synthetic octapeptides linked to the surface of polyethylene pins. A study of the cytotoxicity of mistletoe lectin, ricin, and chimeric toxin MLA/RTB for the hybridomas revealed that interchain disulfide bond reduction and subunit dissociation are required for cytotoxic activity of mistletoe lectin.

摘要

为了研究核糖体失活蛋白的细胞内转运和易位，制备了产生抗槲寄生凝集素A链（MLA）单克隆抗体（mAb）的杂交瘤。抗MLA单克隆抗体MNA5不与全毒素结合，但与分离的MLA相互作用。MLA变性或MLA与蓖麻毒素结合亚基（RTB）偶联后，该表位不被识别。此外，这些单克隆抗体与连接在聚乙烯针表面的一组MLA合成八肽没有明显反应。对杂交瘤中槲寄生凝集素、蓖麻毒素和嵌合毒素MLA/RTB的细胞毒性研究表明，链间二硫键还原和亚基解离是槲寄生凝集素细胞毒性活性所必需的。