At the embryonic stage, single-embryo RNA-sq or immunofluorescence staining was performed to confirm KD or marker gene expression. Cells had been suspended in FACS buffer for 30 minutes. The following day, slices were washed with TBS-T, stained with the appropriate Alexa Fluor-conjugated secondary antibodies (1,250, Thermo Fisher Scientific) or Alexa Fluor-conjugated streptavidin (1,1,000, Thermo Fisher…