Infected Cells
RNA was isolated from vesicles or virus obtained from 20 L cultures. For cellular RNA preparation, 100ml cells were collected (10,000g, 10 min, 4 oC) and stored at -80 oC until extraction. Total RNA (including RNA from approximately 18 nucleotides and higher) was extracted using the miRNeasy kit according to the manufacturer’s instructions (Qiagen, Hilden, Germany). Libraries were prepared using the TruSeq® Small RNA Library kit (Illumina), according to Illumina's protocol with slight modification. After PCR amplification (14 cycles for RNA from control and infected cells and 20 cycles for all other samples), the samples were run on 4% agarose E-gel (E-Gel EX Gels, 4%, Invitrogen), then the cDNA below 300bp was cut and the library was purified using Mini Elute columns (Qiagen), according to the manufacturer’s instructions.