Photoprotection in intact leaves

 16 September 2020                     

 Credit: BNC / R. Ünnep

Small-angle neutron scattering (SANS) is an ideal tool to investigate dynamic remodelling of the multilamellar photosynthetic membranes. In the present article, the authors disclosed the relationship between one of the most important photoprotective mechanisms, the non-photochemical quenching of the excess absorbed quanta that cannot be used in photosynthesis, and the ultrastructural changes of the photosynthetic membranes in intact leaves. With the aid of time-resolved SANS measurements, both the magnitude and kinetics of fast membrane reorganizations associated with this protoprotective mechanism could be determined in vivo.

Two-dimensional and one-dimensional (insets) small-angle neutron scattering profiles of heavy-water infiltrated M. deliciosa leaf
segment in the dark (left), upon illumination with white light of 300 µmol photons m-2 s-1 (middle), and in redark (right) 
Nehézvízzel infiltrált könnyezőpálma levéldarab kétdimenziós és a hozzátartozó egydimenziós kisszögű neutronszórási profilja sötétben (bal), 300 µmol foton m-2 s-1 intenzitású fénnyel történő megvilágítás hatására (közép) és a fény kikapcsolását közetően (jobb)

R. Ünnep, S. Paul, O. Zsiros, L. Kovács, N.K. Székely, G. Steinbach, M.-S. Appavou, L. Porcar, A.R. Holzwarth, G. Garab, G. Nagy "Thylakoid membrane reorganizations revealed by small-angle neutron scattering of Monstera deliciosa leaves associated with non-photochemical quenching", Open Biology, 10:200144 (2020)                                                            http://dx.doi.org/10.1098/rsob.200144