library_construction_protocol: After the zebrafish head genome was extracted, the chromatin was ultrasonographed with covaris. Using the Vazyme DNA library building kit, all DNA samples after IP extraction and DNA before 100ng IP extraction were input, and 13 and 6 (input) cycles were used on the thermal cycler to amplify the library. Use DNA clear beads from Vazyme to select after-expansion beads in 150-250bp length. The library was verified using Q-seq.