A novel splice donor site at nt 1534 is required for long-term maintenance of HPV31 genomes.
Human papillomaviruses (HPV) are small double-stranded DNA viruses that replicate as low copy number nuclear plasmids during the persistent phase. HPV only possess nine open reading frames but extend their coding capabilities by alternative RNA splicing. We have identified in cell lines with replicating HPV31 genomes viral transcripts that connect the novel splice donor (SD) sites at nt 1426 and 1534 within the E1 replication gene to known splice acceptors at nt 3295 or 3332 within the E2/E4 region. These transcripts are polyadenylated and are present at low amounts in the non-productive and productive phase of the viral life cycle. Mutation of the novel splice sites in the context of HPV31 genomes revealed that the inactivation of SD1534 had only minor effects in short-term replication assays but displayed a low copy number phenotype in long-term cultures which might be due to the expression of alternative E1;E4 or yet unknown viral proteins. This suggests a regulatory role for minor splice sites within E1 for papillomavirus replication.
Poppelreuther
Sven
S
Sektion Experimentelle Virologie, Institut für Medizinische Virologie und Epidemiologie der Viruskrankheiten, Universitaetsklinikum Tuebingen, Elfriede-Aulhorn-Str. 6, 72076 Tuebingen, Germany.
Iftner
Thomas
T
Stubenrauch
Frank
F
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018628:Gene Dosage; D015967:Gene Expression Regulation, Viral; D016679:Genome, Viral; D006801:Humans; D015603:Keratinocytes; D051379:Mice; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D009856:Oncogene Proteins, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D027383:Papillomaviridae / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D022821:RNA Splice Sites / Q000235:genetics*; D012326:RNA Splicing; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014779:Virus Replication
D004268:DNA-Binding Proteins; C118863:E1 protein, Human papillomavirus type 31; C098597:E2 protein, Human papillomavirus type 31; D009856:Oncogene Proteins, Viral; D022821:RNA Splice Sites; D014764:Viral Proteins