Duplication and expression of horizontally transferred polygalacturonase genes promote host range expansion of mirid bugs

Identification of polygalacturonase genes in different mirid bugs.RNA was isolated from adults of three mirid bugs using the TRIzol (Invitrogen) reagent by following the company manual. Poly(A) mRNA was isolated from 20 µl total RNA using Oligo (dT) magnetic beads and then was broken into short fragments (about 200bp) in the presence of fragmentation buffer at 94 °C for 5 min. The mRNA samples were used to construct the cDNA libray with mRNA-Seq assay, which was performed by Novogene (Beijing, China).The libraries were sequenced using HiSeq2000 (Illumina) in paired-end mode, creating reads with a length of 100 bp.