The Role of Calcium in Intracellular Trafficking

M.      Micaroni

doi:10.2174/156652410793384204

Abstract

The molecular mechanism of membrane fusion essential to vital cellular activities such as intracellular transport, hormone secretion, enzyme release, or neurotransmission, involve the assembly and disassembly of a specialized set of proteins in opposing bilayers. Recent evidences shed new light on the role Ca2+ has in the regulation of this mechanism in which the Golgi apparatus works as a central station; from here, Ca2+ ions are released into and recovered from the cytosol during the different steps of the cargo progression. In fact, transient cytosolic Ca2+ fluctuations take a crucial role to recruit proteins and enzymes Ca2+-sensitive on Golgi membranes where they are involved in membranes remodelling which is fundamental process for the fusion events that allow protein trafficking. Here I provide an overview of the role Ca2+ plays in intra-Golgi trafficking underlying some interesting aspects to clarify the mechanisms of cargo progression.

Keywords: ATPase calcium pump, calcium, Golgi apparatus, intra-Golgi trafficking, membrane fusion, secretory pathway, SERCA, SPCA, endocytic pathways, Chelation, exocytosis, thapsigargin, yeast, Caenorhabditis elegans, chloroquine, cytotoxicity, synaptic exocytosis, voltage-gated Ca2+ channels, Transient gradients, homeostasis, glycosylation