图3. RSV粗提物从外源mRNA的“抓帽”
M：DNA marker。A：以正常或热失活RSV粗提物进行体外“抓帽”,然后利用巢式RT-PCR扩增含珠蛋白-α帽子序列的RSV NCP（孔1和3）或NP（孔2和4） mRNA,以RT-PCR扩增vcRNA4上NCP对应区域（孔6和8）或vRNA3上NP对应区域（孔5和7）;B：在0—1.5 mmol·L^-1帽子类似物m⁷G (5′) ppp (5′) G存在下进行体外“抓帽”,然后以巢式RT-PCR扩增含珠蛋白-α帽子序列的RSV NCP（孔1—4）,以RT-PCR扩增vcRNA4上NCP对应区域（孔5—8）

Fig. 3. The cap-snatching of crude RSV preparations from exogenously supplied mRNAs
M：DNA marker。A：Untreated or heat inactivated RSV crude preparations were used in the in vitro cap-snatching assay. Nested RT-PCR was used to detect RSV NCP (lanes 1 and 3) or NP (lanes 2 and 4) mRNAs with capped-RNA leaders derived from globin-α. RT-PCR was used to detect a NP-corresponding region on RSV vRNA3 (lanes 5 and 7) or a NCP-corresponding region on RSV vcRNA4 (lanes 6 and 8);B：The cap analog m⁷G (5′) ppp (5′) G was added at a final concentration of 0.5, 1 or 1.5 mmol·L^-1. Nested RT-PCR was used to detect RSV NCP with capped-RNA leaders derived from globin-α (lanes 1 to 4) and RT-PCR was used to detect a NCP-corresponding region on RSV vcRNA4