RNase Y + RNase Y
rRNAs removal: Ribo-Zero rRNA Removal Kit (Illumina); RppH (New England Biolabs) treatment; sonication (Covaris M220), fragments of 200 nt; T4 Polynucleotide kinase (Thermo Scientific); intermediate purification steps with RNA Clean & Concentrator kit (Zymo Research), henol:Chloroform:Isoamylalcohol (Roth) and Chloroform:Isoamylalcohol (Sigma). NEXTflex Small RNA Sequencing Kit v3 (Bioo Scientific) following manufacturers instructions until step G (22 cycles PCR). Libraries purification (substituting step H) with Agencourt AMPure XP beads (Beckman Coulter) following instructions from step I of the NEXTflex Rapid Directional qRNA-Seq Kit (Bioo Scientific). Quality control steps using Qubit (RNA BR Assay and dsDNA HS Assay) or bioanalyzer (RNA 6000 Nano Kit and High Sensivity DNA Kit). Sequencing at the Max Planck-Genome-Centre Cologne, Germany.