RNA-seq of earthworms
Live earthworm species individuals were collected in 20162019. RNA was extracted by the Trizol method. For large worms, RNA was extracted from a section of the body containing the clitellum; for small individuals, the whole body was used. RNA was purified using PureLink RNA Micro Kit (Invitrogen, USA). RNASeq library preparations were carried out with 1 g of total RNA using TruSeq Stranded mRNA LT Sample Prep Kit (Illumina, USA) according with the manufacturers instructions with small modifications (4 min RNA fragmentation time and 12 PCR cycles was used). Sequenced on NextSeq550 sequencer using NextSeq 550 Mid Output v2 Kit 150 cycles (Illumina, USA).