Analysis of the expression ACS and ACO genes in petals from dl flowers. Total RNA was obtained from petals collected from flowers at anthesis (A) and from pollinated and non-pollinated flowers at 4, 12, 24, 48, and 72 h after anthesis. For ACS gene expression, RPA analysis was performed using 30 μg of total RNA per sample. The accumulation of ACO transcripts was examined by RNA gel-blot analysis using 15 μg of total RNA. Gels were stained with ethidium bromide to ensure equal loading of the samples.