title: miRNA profiling of Rattus norvegicus : newborn(P5)
design: Total RNA was isolated using the Trizol Reagent (Invitrogen Life Technologies), after which the concentration, quality and integrity were determined using a NanoDrop spectrophotometer(Thermo Scientific).   Small RNA libraries were constructed using the NEBNext Multiplex Small RNA Library Prep Set for Illumina (New England Biolabs, Inc.) according to the manufacturers instructions.   Briefly, 1g of total RNA from the samples was ligated to a 3adapter and a 5adapter using Ligation Enzyme Mix.  The resulting samples were reverse-transcribed using Superscript II reverse transcriptase.   Amplification was executed for the PCR products.   All steps were performed according to the manufacturer's protocols.  Small RNA libraries were analyzed for QC and average size of inserts was approximately 140 to 150 bp.  The sequencing library was quantified using the Agilent high sensitivity DNA assay on a Bioanalyzer 2100 system (Agilent) and was then sequenced on NovaSeq 6000 platform (Illumina) by Shanghai Personal Biotechnology Cp. Ltd.