Lack of Canonical E6 and E7 Open Reading Frames in Bird Papillomaviruses: Fringilla coelebs Papillomavirus and Psittacus erithacus timneh Papillomavirus

Determination and analyses of the complete sequence of Fringilla coelebs papillomavirus and Psittacus erithacus timneh papillomavirus indicate that they represent a distinct and distant lineage of papillomaviruses. The lack of canonical E6-E7 open reading frames suggests that they serve adaptive functions during papillomavirus evolution.