The present invention identifies a protein, designated the D-sequence-binding protein (D-BP), is phosphorylated at tyrosine residues and blocks AAV-mediated transgene expression in infected cells by inhibiting the leading strand viral DNA synthesis. More particularly, the present invention demonstrates that D-BP is phosphorylated by EGF-R protein tyrosine kinase. Methods of increasing transcription and promoting replication of transgenes exploiting this information are disclosed herein.