Regulatory roles of phosphoinositides in membrane trafficking and their potential impact on cell-wall synthesis and re-modelling.
BACKGROUND
Plant cell walls are complex matrices of carbohydrates and proteins that control cell morphology and provide protection and rigidity for the plant body. The construction and maintenance of this intricate system involves the delivery and recycling of its components through a precise balance of endomembrane trafficking, which is controlled by a plethora of cell signalling factors. Phosphoinositides (PIs) are one class of signalling molecules with diverse roles in vesicle trafficking and cytoskeleton structure across different kingdoms. Therefore, PIs may also play an important role in the assembly of plant cell walls.


METHODS
The eukaryotic PI pathway is an intricate network of different lipids, which appear to be divided in different pools that can partake in vesicle trafficking or signalling. Most of our current understanding of how PIs function in cell metabolism comes from yeast and mammalian systems; however, in recent years significant progress has been made towards a better understanding of the plant PI system. This review examines the current state of knowledge of how PIs regulate vesicle trafficking and their potential influence on plant cell-wall architecture. It considers first how PIs are formed in plants and then examines their role in the control of vesicle trafficking. Interactions between PIs and the actin cytoskeleton and small GTPases are also discussed. Future challenges for research are suggested.
Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany.
Praveen
P
Krishnamoorthy
Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany.
Clara
C
Sanchez-Rodriguez
Martin-Luther-University Halle-Wittenberg, Institute for Biochemistry, Department of Cellular Biochemistry, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany Persson@mpimp-golm.mpg.de Ingo.heilmann@biochemtech.uni-halle.de.
Ingo
I
Heilmann
Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Parkville, VIC 3010, Australia Persson@mpimp-golm.mpg.de Ingo.heilmann@biochemtech.uni-halle.de.
Staffan
S
Persson
D001692:Biological Transport; D002473:Cell Wall / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D007425:Intracellular Membranes / Q000378:metabolism*; D008954:Models, Biological; D010716:Phosphatidylinositols / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D015398:Signal Transduction
D010716:Phosphatidylinositols
PI; Phosphoinositide; actin; cytoskeleton; endocytosis; exocytosis; plant cell wall; small GTPase; vesicle trafficking