library_construction_protocol: Tissues were frozen on dry ice, and RNA was harvested using Trizol reagent. After the total RNA was extracted from the sample, the ribosomal RNA was removed to retain all coding RNA and ncRNA. The obtained RNA was randomly broken into short fragments, and then the first strand of cDNA was synthesized with six base random primers using the fragmented RNA as the template; Then, buffer, dNTPs (dUTP instead of dTTP), RNase H and DNA polymerase I were added to synthesize the second strand of cDNA, which was purified by QiaQuick PCR kit and eluted with EB buffer, repaired at the end, added base A and adapter, and then degraded the second strand by UNG (Uracil-N-Glycosylase) enzyme. Agarose gel electrophoresis was used for fragment size selection and PCR amplification.