Laboratório Nacional de Biociências, Centro Nacional de Pesquisa em Energia e Materiais, Campinas SP, Brazil.
J Proteome Res. 2010 Sep 3;9(9):4595-603. doi: 10.1021/pr100314q.
The human proteins FEZ1 (fasciculation and elongation protein zeta 1) and FEZ2 are orthologs of the protein UNC-76 from C. elegans, involved in the growth and fasciculation of the worms axon. Pull down assays showed that the protein FEZ1 interacts with other proteins (e.g., the protein SCOCO, short coiled-coil protein), mitochondria, and vesicles. These components may therefore represent cargoes to be transported along the microtubule, and the transport may be mediated through FEZ1 reported binding to kinesins (KIF3A). We previously showed that FEZ1 dimerizes in its N-terminal region and interacts with other proteins, including the candidate cargoe proteins, through its C-terminus. Here, we studied the fragment FEZ1(92-194) as well as full-length 6xHis-FEZ1 (1-392) in vitro and endogenous FEZ1 isolated from HEK 293 cells and were able to demonstrate the formation of an intermolecular disulfide bond through FEZ1 Cys-133, which appears to be essential for dimerization. This disulfide bond may be important for the FEZ1 role as a dimeric and bivalent transport adaptor molecule, since it establishes a strong link between the monomers, which could be a prerequisite for the simultaneous binding of two cargoes.
人类蛋白质 FEZ1(束状和延伸蛋白 zeta 1)和 FEZ2 是秀丽隐杆线虫 UNC-76 蛋白的同源物,参与线虫轴突的生长和束状化。下拉测定表明,FEZ1 蛋白与其他蛋白质(例如,SCOCO 蛋白,短螺旋卷曲蛋白)、线粒体和囊泡相互作用。因此,这些成分可能代表要沿微管运输的货物,并且可以通过 FEZ1 报告的与驱动蛋白(KIF3A)的结合来介导运输。我们之前表明,FEZ1 在其 N 端区域二聚化,并通过其 C 端与其他蛋白质(包括候选货物蛋白)相互作用。在这里,我们研究了体外 FEZ1(92-194)片段以及全长 6xHis-FEZ1(1-392)和从 HEK 293 细胞中分离出的内源性 FEZ1,能够证明通过 FEZ1 Cys-133 形成分子间二硫键,这似乎对二聚化至关重要。这种二硫键对于 FEZ1 作为二聚体和二价运输衔接分子的作用可能很重要,因为它在单体之间建立了牢固的联系,这可能是同时结合两个货物的前提。