Restano-Cassulini Rita, Olamendi-Portugal Timoteo, Zamudio Fernando, Becerril Baltazar, Possani Lourival Domingos
Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad, 2001, Col. Chamilpa, Cuernavaca, 62210, Mexico.
Neurochem Res. 2008 Aug;33(8):1525-33. doi: 10.1007/s11064-008-9634-8. Epub 2008 Mar 13.
Voltage-gated potassium channels of the ether-a-go-go related gene (ERG) family are implicated in many important cellular processes. Three such genes have been cloned (erg1, erg2 and erg3) and shown to be expressed in the central nervous system (CNS) of mammalians. This communication describes the isolation and characterization of two isoforms of scorpion toxin (CeErg4 and CeErg5, systematic nomenclature gamma-KTx1.7 and gamma-KTx1.8, respectively) that can discriminate the various subtypes of ERG channels of human and rat. These peptides were purified from the venom of the Mexican scorpion Centruroides elegans elegans. They contain 42 amino acid residues, tightly folded by four disulfide bridges. Both peptides block in a reversible manner human and rat ERG1 channels, but have no effect on human ERG2. They also block completely and irreversibly the rat ERG2 and the human ERG3 channels hence are excellent tools for the discrimination of the various sub-types of ion-channels studied.
醚 - 去极化相关基因（ERG）家族的电压门控钾通道参与许多重要的细胞过程。已克隆出三个这样的基因（erg1、erg2和erg3），并显示它们在哺乳动物的中枢神经系统（CNS）中表达。本通讯描述了两种蝎毒素同工型（CeErg4和CeErg5，系统命名分别为γ-KTx1.7和γ-KTx1.8）的分离和特性，它们能够区分人和大鼠ERG通道的各种亚型。这些肽是从墨西哥蝎Centruroides elegans elegans的毒液中纯化出来的。它们含有42个氨基酸残基，通过四个二硫键紧密折叠。这两种肽都以可逆方式阻断人和大鼠的ERG1通道，但对人ERG2没有影响。它们还能完全且不可逆地阻断大鼠ERG2和人ERG3通道，因此是区分所研究的各种离子通道亚型的优秀工具。
