PHF5A and viral infectious disease: This indicates that U2 snRNP blocks AAV vectors at a particular post-entry step of viral infection, likely occurring before 24 hours p.i. Similar to PHF5A disruption, meayamycin B also enhanced the transduction by both single-stranded AAV and scAAV vectors through increasing the number as well as the fluorescent intensity of GFP-positive cells (Fig 3H).