Helianthus annuus seed transcriptome
RNA Extraction : RNA was extracted from dehulled mature sunflower seeds using the hot phenol method as described in Mylne et al., 2012, Plant Cell 24: 2765-2778. The total RNA solution was purified further using the NucleoSpin RNA Clean-up kit (Machery-Nagel). The quality of the RNA was tested by measuring the A260/280 and A260/230 ratios using a NanoDrop Spectrophotometer (ND-1000 Spectrophotometer, ThermoFisher Scientific) and visualizing on a 1% agarose gel stained with ethidium bromide. Library Construction : The total RNA solution was enriched by BGI Genomics (Beijing, China) for poly(A) mRNA using oligo(dT) beads, the mRNA was fragmented and used as a template for first-strand cDNA synthesis using random hexamers. The second strand cDNA was synthesized, short fragments purified with QIAQuick PCR extraction kit, the ends repaired and then connected to sequencing adapters. After a final size selection, the library was sequenced using an Illumina HiSeq 2000. Data processing : Clean reads were obtained by filtering adaptors, contamination and low-quality reads from the raw reads.