The Golgi ribbon and the function of the golgins

Abstract

The Golgi apparatus (GA) is present in different organisms in very different forms. When visualized by immunof luorescence in most mammalian cells, the Golgi ribbon appears as a lacy structure that occupies a volume of 5-7μm in length, 1-2μm in width, and 3-5μm in depth (Storrie and Kreis 1996), and that surrounds the centrosome (or microtubule-organizing centre; MTOC) (see Chapter 2.14). The positions of the MTOC and the GA depend on cell polarity. In many polarized epithelial cells, the centrosome is positioned near the apical portion of the cell surface (Ojakian et al. 1997), where the GA also resides. From dozens to hundreds of Golgi stacks that act as a single organelle are linked together to form an interconnected, ribbon-like structure in the perinuclear area (Hidalgo Carcedo et al. 2004; Polishchuk and Mironov 2004; Mogelsvang et al. 2004). Completely isolated stacks are rare (Cole et al. 1996a, b).