title: Burnt-end Ark: adult haemolymph
design: 1. mRNA enrichment: After qualified RNA detection, magnetic beads with Oligo (dT) were first used to enrich eukaryotic mRNA through A-T complementary pairing and ployA tail binding of mRNA; 2. fragmentation: mRNA was divided into short fragments by fragmentation buffer reagent. 3. Reverse transcription: mRNA was used as template to synthesize a cDNA strand with six-base random hexamers, and then buffer solution, dNTPs and DNA polymerase I were added to synthesize a two-strand cDNA, and then AMPure XP beads were used to purify the double-strand cDNA. 4. Terminal repair: the repaired cDNA was completed and purified, cDNA3 'end was added with A (dA-tailing); 5. Connection joints: Each joint has a 6bp index, also called barcode. Different index joints are used for each sample. 6. Fragment selection and PCR enrichment: AMPure XP beads were used for fragment size selection, and finally PCR enrichment was carried out to get the final cDNA library for sequencing.