Phosphatidylinositol-specific phospholipase C interaction with G-proteins in relation to the environmental stress response in wheat (Triticum aestivum).

摘要

Tolerance to environmental stress in plants is controlled by several internal factors and environmental signals. In this study, we have focused on phosphatidylinositol-specific phospholipase C (TaPI-PLC) and phosphoglycerol-specific phospholipase C (TaPG-PLC) in wheat, Triticum aestivum . Three homologs of TaPG-PLCs were identified as cDNA with high sequence similarity to rice and Arabidopsis PG-PLC1. TaPG-PLC3 was mapped on the distal part of the long arm of chromosome 5A, whereas TaPG-PLC1 and TaPG-PLC2 like genes appear to be duplicated in two of hexploid wheat 3 three genomes. A TaPG-PLC1::Green fluorescent protein (GFP)-fusion was localized on endoplasmic reticulum (ER), golgi and plasma membrane (PM). Important protein-protein interactions were found for wheat PI-PLCs. The PI-PLCI::GFP fusion was localized on ER-and PM. In vivo interactions between TaPI-PLC1 and two classes of G-proteins, the heterotrimeric G protein subunit TaGa and a non-canonicat G-protein J822, were detected using Bimolecular Fluorescent Complementation (BiFC). The interactions were detected in both the ER and PM. In contrast, TaPI-PLC2::GFP fusion was localized only on PM and was not found to interact with TaGalpha or J822 . Since both TaPI-PLC 1 and J822 are up-regulated by cold stress and it is possible that they play an important role in signaling during cold acclimation.