Figure 8.

DEAP2 can partially compensate for loss of PAM68 but not vice versa. A) Pictures (upper panel) and false color images of the maximum quantum yield of photosystem (PS)II (Fv/Fm, lower panel) of 6-week-old wild type (WT), deap2-1, cDEAP2-1, pam68-2, deap2-1 overexpressing PAM68 (deap2-1 35S:PAM68), pam68-2 overexpressing PAM68 (oePAM68) or DEAP2 (pam68-2 35S:DEAP2). All overexpressed proteins carry a c-terminal MYC-tag. Three independent lines with varying amounts of protein expression were selected (Supplemental Fig. 7). Shown here are lines #1 and #3 with lowest and highest Myc-tagged protein levels as determined by immunoblotting. Signal intensities for Fv/Fm were calculated from chlorophyll fluorescence analyses and are reflected by the false color scale beside the panels. B and C) Fv/Fm (B) and leaf area (C, shown as square root) from n = 6–10 genotypes as shown in (A) with error bars indicating standard deviation. Capital letters above graphs indicate groups with significant differences between genotypes (P < 0.05) as determined by one-way ANOVA and Holm-Sidak multiple comparison test. D) Immunoblot analysis of total protein extracts using specific antibodies against DEAP2 and PAM68 (left panel) and PSII subunits (right panel). The accumulation of subunits of other thylakoid complexes is shown in Supplemental Fig. 7. Ponceau red (P.R.) staining of one membrane prior to immunodetection is shown as a loading control. The additional thick line in the left panel indicates plant lines with varying PAM68 levels, revealing the inverse response of DEAP2 accumulation.