Rps18

cDNA synthesis and qPCR were performed using a previously reported method^{30 (link)}, with slight modifications. Briefly, cDNA was synthesized using the PrimeScript RT reagent kit (Takara Bio) with oligo(dT) primers and 1 μg of total RNA. The synthesized cDNA was mixed with SYBR Premix Ex Taq II (Takara Bio) and specific primers. Amplification was performed for 50 cycles, each at 95 °C for 15 s and 60 °C for 1 min, using a StepOnePlus real-time PCR system (Thermo Fisher Scientific). The list of primers used is presented in Supplementary Table S7. All measurements were performed in duplicate. For quantifying the levels of GAPDH and RPS18, a calibration curve was generated using 10, 5, 2.5, 1.25, 0.625, and 0.3125 fM synthetic DNA, which included the target sequence (GAPDH, GenScript Japan, Tokyo, Japan; RPS18, Integrated DNA Technologies, Coralville, IA, USA). The list of synthetic DNA sequences used is provided in Supplementary Table S8. For gel images, amplification was performed for 35 cycles, each at 95 °C for 15 s and 60 °C for 1 min, using an Applied Biosystems 2720 Thermal Cycler (Thermo Fisher Scientific).