Teun Munnik

..For several of them, a relationship to water stress has been reported. This review summarizes the current status of PPIs and IPPs in plants and discusses their potential in osmotic stress signalling and drought...

..Such lipid-binding domains have also been used to create GFP based-lipid biosensors to visualize PPIs dynamics in vivo. Here, we highlight some recent advances and ideas on PPIs' role in plant signalling...

..Below, these are described "in a nutshell."..

..Furthermore, we show that both PLDs are activated upon dehydration and the knock-out mutants are hypersensitive to hyperosmotic stress, displaying strongly reduced growth...

..truncatula and A. thaliana, a clear PtdIns4P gradient was apparent in the plasma membrane, with the highest concentration in the tip. This only occurred in growing root hairs, indicating a role for PtdIns4P in tip growth...

..Together, these data show that YFP-2xFYVE may be used as a biosensor to specifically visualize PtdIns3P in living plant cells...

..New roles for PtdIns(4,5)P(2) in plant cell signalling are discussed...

..Moreover, larvae of the Cabbage White butterfly (Pieris rapae) grew equally well on wild-type and the pld knock-out mutants...

..These results are discussed in the context of the diverse cellular roles played by PIP(2) and PA, including regulation of ion channels and the cytoskeleton...

..Plants exploit hydrodynamics to drive processes including gas exchange, leaf positioning, nutrient acquisition and growth. This paradigm is extended by recent work that reveals an important role for hydrodynamics in pollen tube growth...

..Using these novel insights, we propose a model for the mechanism by which PLD activation triggers microtubule reorganization in plant cells...

..Possible functions for PLDbeta in plant-pathogen interactions are discussed...

..Several protein targets have now been discovered that bind PA. Whether the PA molecules engaged in these interactions come from PLD or DGK remains to be elucidated...

..Moreover, the first protein targets of PA have been identified. Based on this recent work, potential mechanisms by which PA provokes downstream effects are emerging...

..PLD and its product, phosphatidic acid, exert their effects by functioning in signal transduction cascades and by influencing the biophysical state of lipid membranes...

..However, mutations in this motif did not affect either PA-binding or PA-dependent inhibition of CTR1 activity. Subsequent deletion analysis of CTR1's kinase domain revealed a novel PA-binding region at the C-terminus of the kinase...

..In S. cerevisiae, the expression of DPP1 is regulated coordinately with the majority of genes encoding enzymes involved in phospholipid biosynthesis...

..Together these results show that salt stress rapidly activates several lipid responses in rice leaves but that these responses do not explain the difference in salt tolerance between sensitive and tolerant cultivars...

..The ACE model involves delivery and recycling of materials required for new cell synthesis and the H model involves mechanisms that integrate and regulate key cellular pathways and drive cell elongation during growth...

..Through characterization of several of these PA targets, a molecular and genetic basis for PA's role in plant stress and development is emerging...

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..However, whereas phospholipase C and DAG kinase were activated during treatment with all three different compounds, PLD was only activated by Nod factor. No evidence was obtained for the activation of phospholipase A(2)...

..4/2.10 to membranes upon exposure to salt, supporting their observed binding affinity for the phospholipid phosphatidic acid. Together, our results reveal a role for SnRK2.4 and -2.10 in root growth and architecture in saline conditions...

..This suggests that PEPC's affinity for PA had increased. The work shows that PA-affinity chromatography/mass spectrometry is an effective way to isolate and identify PA-binding proteins from plants...

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..The combined results suggest that hydrodynamic loading/unloading in the apical region induces cell volume oscillations and has a role in driving cell elongation and pollen tube growth...

..The same lipid-binding domains are present in Arabidopsis proteins. We believe that they represent an untapped well of information about plant lipid signalling...

..This was because the PLC/DGK pathway was activated as well, resulting in phosphoinositide-specific fatty acids and molecular species in PA...

..This report provides crucial spatial and temporal details of vesicle trafficking and anisotropic growth...

..These results may have broader significance for plant cell growth...

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