Plant phospholipid signaling: “in a nutshell”

Abstract

Since the discovery of the phosphoinositide/ phospholipase C (PI/PLC) system in animal systems, we know that phospholipids are much more then just structural components of biological membranes. In the beginning, this idea was fairly straightforward. Receptor stimulation activates PLC, which hydrolyses phosphatidylinositol4,5-bisphosphate [PtdIns(4,5)P 2 ] into two second messengers: inositol 1,4,5-trisphosphate (InsP 3 ) and diacylglycerol (DG). While InsP 3 difuses into the cytosol and triggers the release of calcium from an internal store via ligand-gated calcium channels, DG remains in the membrane where it recruits and activates members of the PKC family. The increase in calcium, together with the change in phosphorylation status, (in)activates a variety of protein targets, leading to a massive reprogramming, allowing the cell to appropriately respond to the extracellular stimulus. Later, it became obvious that not just PLC, but a variety of other phospholipid-metabolizing enzymes were activated, including phospholipase A, phospholipase D, and PI 3-kinase.

Nonspecific Phospholipase C NPC4 Promotes Responses to Abscisic Acid and Tolerance to Hyperosmotic Stress inArabidopsis

“…Phospholipase D (PLD) hydrolysis of membrane lipids directly produces signaling PA. It has been shown recently that PLDa3, «, d, and a1 contribute to hyperosmotic stress-induced PA production and affect plant response to hyperosmotic stress in Arabidopsis thaliana (Hong et al, 2008(Hong et al, , 2009Munnik and Testerink, 2009). Activation of phospholipase C (PLC) is another major route for generating the PA signal.…”

A Small Phospholipase A2-α from Castor Catalyzes the Removal of Hydroxy Fatty Acids from Phosphatidylcholine in Transgenic Arabidopsis Seeds

“…They are involved in several biological processes in both animals and plants (Chen et al, 2011): (1) as a component of the acylation/ hydrolysis of phospholipids in the so-called Lands cycle involved in primary lipid metabolism in animals (Lands, 1960;Balsinde and Dennis, 1997;Imae et al, 2010) and plants (Li et al, 2013); (2) in membrane architecture and trafficking (Lee et al, 2010;Kim et al, 2011); (3) in the production of bioactive compounds involved in signaling, pathogen defense, and programmed cell death (Munnik and Testerink, 2009;Canonne et al, 2011); (4) in catalyzing the hydrolysis of oxidized lipids (van Kuijk et al, 1987;Banas et al, 1992); (5) in seed storage lipid mobilization (Rudolph et al, 2011);and (6) in uncommon and modified FA production in seeds (Bafor et al, 1991;Ståhl et al, 1995;Bates and Browse, 2011).…”

“…The third group contains four paralogous genes coding for low-molecular-mass PLA 2 s of around 14 kD, sPLA 2 a, sPLA 2 -b, sPLA 2 -g, and sPLA 2 -d Matos and Pham-Thi, 2009). Evidence for the involvement of sPLA 2 in signaling and pathogen defense is more limited (Munnik and Testerink, 2009;Canonne et al, 2011). Their involvement in membrane trafficking, however, is emerging: reductions in sPLA 2 expression in Arabidopsis (Arabidopsis thaliana) plants led to Golgi disruption and the inhibition of PIN auxin efflux transporter traffic to the plasma membrane in roots (Lee et al, 2010) and also to membrane disruption in pollen (Kim et al, 2011).…”

TaCHP: A Wheat Zinc Finger Protein Gene Down-Regulated by Abscisic Acid and Salinity Stress Plays a Positive Role in Stress Tolerance

“…DAG activates PKC (Azzi et al, 1992) and acts as a signal transducer in a Ca 2+ -dependent manner. However, in plants, there is little evidence for the existence of either PKC or any IP3 receptors (Munnik and Testerink, 2008). As a result, the function of DC1 domain-containing proteins in plants remains unclear.…”