Modulating the expression of aquaporin genes in planta: A key to understand their physiological functions?
Aquaporins (AQPs) are believed to act as "cellular plumbers", allowing plants to rapidly alter their membrane water permeability in response to environmental cues. This study of AQP regulation at both the RNA and protein levels has revealed a large number of possible mechanisms. Currently, modulation of AQP expression in planta is considered the strategy of choice for elucidating the role of AQPs in plant physiology. This review highlights the fact that this strategy is complicated by many factors, such as the incomplete characterization of transport selectivity of the targeted AQP, the fact that AQPs might act as multifunctional channels with multiple physiological roles, and the number of post-translational regulation mechanisms. The classification of AQPs as constitutive or stress-responsive isoforms is also proposed.
Unité de Biochimie physiologique, Institut des Sciences de la Vie, Université catholique de Louvain, Croix du Sud 5-15, B-1348 Louvain-la-Neuve, Belgium.
Charles
C
Hachez
Enric
E
Zelazny
François
F
Chaumont
D020346:Aquaporins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D001693:Biological Transport, Active; D002463:Cell Membrane Permeability; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D009994:Osmolar Concentration; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D010944:Plants / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D012492:Salts / Q000378:metabolism; D014867:Water / Q000378:metabolism
D020346:Aquaporins; D010940:Plant Proteins; D012492:Salts; D014867:Water