design: Total RNA samples are qualified by agarose gel electrophoresis and quantified using Nanodrop. We use the commercial kit for tRF & tiRNA-seq library preparation, which includes 3-adapter and 5-adapter ligation adaptor ligation, cDNA synthesis and library PCR amplification. The prepared tRF & tiRNA-seq libraries are finally quantified using Agilent BioAnalyzer 2100, then sequenced using Illumina NextSeq 500.