title: Targeting of tonoplast proteins to the vacuole.
abstract: Vacuoles are essential for plant growth and development, and are dynamic compartments that require constant deposition of integral membrane proteins. These membrane proteins carry out many critical functions of the vacuole such as transporting ions and metabolites for vacuolar storage. Understanding the mechanisms for targeting proteins to the vacuolar membrane, or tonoplast, is important for developing novel applications for biotechnology. The mechanisms to target tonoplast proteins to the vacuole are quite complex. Multiple routes, including both Golgi-dependent and Golgi-independent mechanisms, have been implicated in tonoplast protein trafficking. A few endomembrane proteins that regulate this traffic at the level of the endoplasmic reticulum, the pre-vacuolar compartment and the tonoplast are now known. Recent reports indicate that the Golgi-dependent and independent pathways may merge at the level of the pre-vacuolar compartment. Finally, the small GTP-binding protein Rab7 and the SNARE protein SYP21 have been implicated in the traffic of tonoplast proteins from the pre-vacuolar compartment to the tonoplast. With multiple cargo proteins being analyzed under a variety of experimental systems, a clearer picture for targeting mechanisms for tonoplast proteins is starting to emerge.
authors.affiliation: Department of Plant Biology, North Carolina State University, Raleigh, NC 27695, United States. mrojasp@ncsu.edu
authors.forename: Marcela
authors.initials: M
authors.lastname: Rojas-Pierce
mesh_terms: D002462:Cell Membrane / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D021381:Protein Transport; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D010940:Plant Proteins
keywords: Protein trafficking; Tonoplast protein; Vacuole