Antenna association increases PSI particles resistance to high light treatment. A) PSI particles purified from WT and Lhca4 depleted plants were illuminated with high light (1600 μE) at 10°C for 45 minutes. Absorption spectra were registered during the treatment and the absorption area is reported here (WT, black squares, ΔLhca4 red circles) after normalization of the value before the treatment to 100%. B) The same analysis was done comparing PSI-LHCI from WT (black squares) with isolated PSI core (red diamonds) and LHCI (green triangles). Samples concentrations were normalized to known PSI Chl to protein stoichiometries (170 Chls per PSI-LHCI, 102 per PSI core, 50 per LHCI). SD is also reported, calculated from at least three replicates.