Hubert Thomas, Van Impe Katrien, Vandekerckhove Joël, Gettemans Jan
Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium.
Biochem Biophys Res Commun. 2009 Feb 27;380(1):166-70. doi: 10.1016/j.bbrc.2009.01.064. Epub 2009 Jan 21.
Extensive cross-talk between the actin and the microtubule cytoskeletons has been reported. Especially in mitosis, processes dependent on actin- and microtubule-based structures alternate and regulate each other in a complex cascade leading to division into two daughter cells. Here, we have studied the subcellular localization of the filamentous actin-capping protein CapG. Fluorescence microscopy of endogenous CapG and EGFP-tagged CapG revealed CapG localization at the mother centriole in interphase, the mitotic spindle in mitosis and the midbody ring in abscission. Surprisingly, nucleoporin Nup62, an interaction partner of CapG, also localized to the midbody ring at the end of abscission and colocalized with CapG. We propose a role for the actin-binding protein CapG as a mediator of cross-talk between the actin cytoskeleton and microtubule-based organelles that regulate cell division.
已有报道称肌动蛋白和微管细胞骨架之间存在广泛的相互作用。特别是在有丝分裂过程中,依赖于基于肌动蛋白和微管的结构的过程交替出现,并在一个复杂的级联反应中相互调节,导致细胞分裂为两个子细胞。在这里,我们研究了丝状肌动蛋白封端蛋白CapG的亚细胞定位。对内源性CapG和EGFP标记的CapG进行荧光显微镜观察,结果显示CapG在间期定位于母中心粒,在有丝分裂期定位于有丝分裂纺锤体,在分裂后期定位于中体环。令人惊讶的是,CapG的相互作用伙伴核孔蛋白Nup62在分裂后期结束时也定位于中体环,并与CapG共定位。我们提出肌动蛋白结合蛋白CapG作为肌动蛋白细胞骨架和调节细胞分裂的基于微管的细胞器之间相互作用的介质发挥作用。