Figure 9.
Phenotype of ETF/ETFQO-related Arabidopsis mutants during growth under extended dark conditions. A, RT-PCR analysis on total RNA from the wild type (WT) and the pahx-1, pahx-2, and pahx-3 mutant lines, as well as two double knockout lines ivdhh1-1 × d2hgdh1-2 and etfqo-1 with primer sets for the genes indicated on the left. B, Images of 4-week-old, short-day-grown Arabidopsis plants immediately (0 d) and after further growth for up to 15 d in darkness conditions. The leaves of the pahx mutant lines were only partially yellowed and dehydrated following 15 d growth in darkness compared to the wild-type (WT) control (Col0). Chlorophyll content (C), chlorophyll a/b ratio (D), and Fv/Fm (E), the maximum quantum yield of PSII electron transport, of leaves of 4-week-old, short-day-grown, Arabidopsis plants after further growth for 0, 3, 7, 10, and 15 d in extended darkness. Values are means ± se of six independent samplings; an asterisk indicates values that were determined by the Student’s t test to be significantly different from the wild type (P < 0.05).