Arnica montana seed transcriptome
RNA Extraction : Mature dry A.montana seeds were purchased from the Jelitto perennial seed company, USA. RNA was extracted from whole 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.