replication 2 of SpM03
After the total RNA of male and female flowers was extracted by TRIzol reagent (Life technologies), mRNA was enriched by Oligo (dT) beads. The enriched mRNA was fragmented into short fragments using fragmentation buffer and reverse transcribed into cDNA with random primers. Second-strand cDNA was synthesized by DNA polymerase I, RNase H, dNTP, and buffer. The cDNA fragments were then purified with QiaQuick PCR extraction kit, end repaired, poly(A) added, and ligated to Illumina sequencing adapters. The ligation products were size selected by agarose gel electrophoresis, PCR amplified,and sequenced using Illumina HiSeq? 2510 by Gene Denovo Biotechnology Co..