title: Complete mitochondrial genome of the earthworm
design: gDNA (1 mg) was sheared using the S220 Ultra sonicator (Covaris). Library preparation wasperformed with MGIEasy DNA library prep kit (MGI) according to the manufacturer's instructions.Briefly, After Size-selection of fragmented gDNA using AMPure XP magnetic beads, thefragmented gDNA was end-repaired and a-tailed at 37 C for 30 min, and 65 C for 15 min.Indexing adapter was ligated to the ends of the DNA fragments at 23 C for 60 min. After cleanupof adapter-ligated DNA, PCR was performed to enrich those DNA fragments that have adaptermolecules. Thermocycler conditions were as follows: 95C for 3 min, 7 cycles of 98C for 20 s,60C for 15 s, and 72C for 30 s, with a final extension at 72C for 10 min. The double strandedlibrary is quantified using QauntiFluor ONE dsDNA System (Promega. The library is circularizedat 37 C for 30 min, and then digested at 37 C for 30 min, followed by cleanup of circularizationproduct. To make DNA nanoball (DNB), the library is incubated at 30 C for 25 min using DNBenzyme. Finally, Library was quantified by QauntiFluor ssDNA System (Promega). Sequencing ofthe prepared DNB was conducted on the MGIseq system (MGI) with 150 bp paired-end reads.