The Functions of the Golgin Family of Coiled-Coil Proteins

The golgins are a family of ubiquitously expressed and evolutionary conserved Golgi-localised coiled-coil proteins. The golgins are particularly important for vesicle trafficking and structural organisation of the Golgi apparatus. The golgins mediate tethering, or long-range capture, of transport vesicles to Golgi membranes, a key step in vesicle traffic that ensures the specificity of vesicle transport at the Golgi. Following tethering, the golgins associate with other factors to ensure that vesicles undergo the transition to membrane fusion mediated by SNARE proteins. The golgins also contribute to the structural organisation of the Golgi apparatus, particularly in Golgi ribbon formation. This is achieved in several ways, which includes linking the Golgi membranes to the microtubule cytoskeleton, controlling the activity of cytoskeletal regulators and physically linking Golgi elements into the ribbon. Golgin-dependent interactions with the microtubule cytoskeleton also contribute to cell polarity, migration and division. In addition to regulating Golgi function and organisation, the golgins scaffold various factors to control the activity of these factors in a range of cellular processes which includes signaling, autophagy, spindle assembly and cell fate determination. In this book chapter we discuss current understanding of the golgins and their functional roles in cells.