1. Establishment of the unusual structural features of relaxed circular (RC)-DNA via protein priming.
Establishment of the unusual structural features of relaxed circular (RC)-DNA via protein priming. Protein priming at 5′ ε generates a short ε bulge-templated DNA oligo that is phosphodiester-linked to the terminal protein (TP) domain in P protein and transferred to direct repeat 1* (DR1*) for extension. During (-)-DNA completion, pregenomic (pg)RNA is degraded except for the capped 5′ end, yielding single-stranded (ss) DNA. The undegraded RNA oligo serves as (+)-DNA primer. Direct (in situ) extension yields double-stranded linear (dsL) DNA. Properly primed (+)-DNA synthesis proceeds by transfer of the RNA primer to DR2; after reaching the 5′ end of the (-)-DNA template, the small terminal redundancy r enables exchange against the sequence-identical 3′ r sequence such that (+)-strand synthesis can go on to generate RC-DNA. See text for details.
Michael Nassal Gut 2015;64:
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