The SecretoryPathway The transport ofproteins and lipids from their site ofsynthesis at the endoplasmic reticu- lum (ER) to the cellsurface ismediated by the secretory pathway and isan essential process in eukaryotic organisms. A great variety ofmolecules are extruded from cellsby the action ofthe secretory pathway, including extracellular matrix components that provide the foundation for constructing tissuesand organs. Moreover, this pathway playsa major role in the biogenesisof the plasma membraneand itsexpansion before celldivision. Therefore, withoutsecretion there would be no cells,tissuesor organs, and so it issafeto saythat we oweourvery existence to the secretory pathway. To understand the process ofsecretion we must learn about the organelles that compose the secretory pathway; the ER and Golgi apparatus, and the transport vesicles these or- ganelles produce. The membrane ofthese organelles is primarily synthesized and assembled at the ER but with contributions from mitochondria (phosphatidylethanolamine) and the Golgi apparatus (sphingolipids). Newly synthesized proteins destined for secretion gain en- try into the secretory pathway by translocation across the ER membrane. This translocation apparatus also integrates proteins into the membrane and establishes their topology with respect to the lipid bilayer (seeChapter 7). Many secretory proteins are covalently modified with oligosaccharides to produce glycoproteins, a biosynthetic process initiated in the ER and continued in the Golgi apparatus. Once proteins are properly folded and modified in the ER, they are allowed to leave and are ushered into COPlI-coated carrier vesiclesforming at specific exit sites (see Chapters 1 and 8).

This second edition volume expands on the previous edition with a discussion of new research and discoveries in the Rab field. Chapters in this book cover topics such as new information on Rab regulation and localization; interaction; function; and diseases. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Cutting-edge and comprehensive, Rab GTPases: Methods and Protocols, Second Edition is a valuable resource for scientists working in the fields of Rab and other small GTPases, and beyond.

This second edition volume expands on the previous edition with a discussion of new research and discoveries in the Rab field. Chapters in this book cover topics such as new information on Rab regulation and localization; interaction; function; and diseases. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Cutting-edge and comprehensive, Rab GTPases: Methods and Protocols, Second Edition is a valuable resource for scientists working in the fields of Rab and other small GTPases, and beyond.