Transcript levels of chlorophyll breakdown pathway genes in wild type and <i>nos1/noa1</i> mutant leaves during dark-induced senescence.

<p>(A) A suggestive model for chlorophyll breakdown pathway with integrating the recent findings in Arabidopsis. Thickness of arrows reflects relative activities of respective enzymes (Hörtensteiner, 2009). (B–F) qRT-PCR analysis of mRNA abundance of enzyme genes (<i>SGR</i>, <i>NYC1</i>, <i>PPH</i>, <i>PAO</i> and <i>RCCR</i>) involved in chlorophyll degradation in wild type and <i>nos1/noa1</i> mutant leaves during dark-induced senescence. <i>ACTIN2</i> was used as the internal standard. Error bars indicate standard deviations of three technical replicates, and the results were consistent in three biological replicates.