Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Extensin network formation in Vitis vinifera callus cells is an essential and causal event in rapid and H2O2-induced reduction in primary cell wall hydration | Pereira et al. BMC Plant Biology 2011 11 106 http 1471-2229 11 106 BMC Plant Biology RESEARCH ARTICLE Open Access Extensin network formation in Vitis vinifera callus cells is an essential and causal event in rapid and H2O2-induced reduction in primary cell wall hydration Cristina Silva Pereira1 José ML Ribeiro1 Ada D Vatulescu1 Kim Findlay2 Alistair J MacDougall3 and Phil AP Jackson1 Abstract Background Extensin deposition is considered important for the correct assembly and biophysical properties of primary cell walls with consequences to plant resistance to pathogens tissue morphology cell adhesion and extension growth. However evidence for a direct and causal role for the extensin network formation in changes to cell wall properties has been lacking. Results Hydrogen peroxide treatment of grapevine Vitis vinifera cv. Touriga callus cell walls was seen to induce a marked reduction in their hydration and thickness. An analysis of matrix proteins demonstrated this occurs with the insolubilisation of an abundant protein GvP1 which displays a primary structure and post-translational modifications typical of dicotyledon extensins. The hydration of callus cell walls free from saline-soluble proteins did not change in response to H2O2 but fully regained this capacity after addition of extensin-rich saline extracts. To assay the specific contribution of GvP1 cross-linking and other wall matrix proteins to the reduction in hydration GvP1 levels in cell walls were manipulated in vitro by binding selected fractions of extracellular proteins and their effect on wall hydration during H2O2 incubation assayed. Conclusions This approach allowed us to conclude that a peroxidase-mediated formation of a covalently linked network of GvP1 is essential and causal in the reduction of grapevine callus wall hydration in response to H2O2. Importantly this approach also indicated that extensin network effects on hydration was only partially irreversible and remained .
