Fig. 4
Nuclease-resistance assay of mRNA packaged by the PP7 capsid carrying LMWP. a The purified 2PP7 VLPs, 2PP7-Protamine VLPs and 2PP7-Protamine-GFP VLPs (800 μg/ml) were separately mixed with DNase I (20 U/mL) and RNase A (10 mg/mL), incubated at 37 °C for 12 h, and verified by 1 % agarose gel electrophoresis: lane M, DL 2000 DNA marker; lane 1, 2PP7-Protamine VLPs; lane 2, 2PP7-Protamine-GFP VLPs; lane 3, 2PP7 VLPs. b Verification of nucleic acids packaged by 2PP7-Protamine VLPs (lanes 1, 2, 3, 4; the PP7 coat protein dimer gene containing LMWP was amplified) and 2PP7-Protamine-GFP VLPs (lanes 6, 7, 8, 9; the GFP gene was amplified). The PCR products in different lanes were as follows: lanes 1 and 9, reverse transcription product of RNA extracted from corresponding VLPs; lanes 2 and 8, RNA extracted from corresponding VLPs; lanes 3 and 7, purified VLP sample; lanes 4 and 6, reverse transcription product of purified VLPs sample; lane 5, ddH2O. M1, DL 2000 DNA marker; M2, DL 10000 DNA marker