2.1 Sampling, DNA extraction, and RNA extraction
Wild
adult female C. japonica (approximately 210 g) individuals were
collected in December 2019 from Zhoushan. The animal study and procedure
were approved by the Animal Ethics Committee of Yantai University. Fresh
gill, muscle, heart, and intestinal tissues were collected using
sterilized dissection scissor and scalpel and then snap-frozen in liquid
nitrogen. High-quality genomic DNA was extracted from the muscle tissues
of C. japonica using the Blood & Cell Culture DNA Mini Kit
(QIAGEN, GER), and high-quality RNA was extracted from C.
japonica tissues using the TRIzol Reagent Kit (Invitrogen, USA). The
integrity, purity, and concentration of the genomic DNA were assessed
using 1% agarose gel electrophoresis, NanoDrop 2000 analyzer (Thermo
Fisher Scientific, USA), and Qubit 3.0 analyzer (Thermo Fisher
Scientific, USA). RNA integrity and concentration were measured using
the Agilent Bioanalyzer 2100 System (Agilent Technologies, USA) and
NanoDrop 2000 analyzer (Thermo Fisher Scientific, USA).