Changes in the topography of early region transcription during polyoma virus lytic infection.
AUTOR(ES)
Fenton, R G
RESUMO
We have studied the pattern of transcription of the early region of polyoma virus DNA after the onset of the late phase of lytic infection of mouse cells. Following initiation of viral DNA synthesis, the early/late switch is accompanied not only by efficient production of late mRNAs but also by the appearance of previously unidentified early-strand RNAs which have certain structural features in common with the classical early mRNAs. Stable poly(A)+RNAs have been identified by blot analysis and S1 nuclease mapping that are not detected early during infection or in polyoma virus-transformed cells. One group consists of transcripts whose 5' ends map 150-200 nucleotides upstream from the major early 5' ends (at positions 148 and 153 on the polyoma virus genome) but whose splicing pattern and poly(A) addition sites are indistinguishable from those of mRNAs produced early in infection. The 5' exons of these early region transcripts contain an open translational reading frame that extends from nucleotide positions 5,255 to 124 and is capable of encoding a basic protein of 53 amino acids. Transcription of these RNAs does not appear to be negatively regulated by large tumor antigen. A transcript of 1,800 nucleotides appears to map predominantly between 93 and 26 map units and does not contain sequences present in the early mRNA 5' exons. These data suggest that, after the onset of polyoma DNA replication, the activation of new early-strand promoters leads to the expression of previously untranscribed viral DNA sequences.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=347294Documentos Relacionados
- Extent of Transcription of the E Strand of Polyoma Virus DNA During the Early Phase of Productive Infection
- Adenovirus early region 4 encodes two gene products with redundant effects in lytic infection.
- Epstein-Barr virus induces fragmentation of chromosomal DNA during lytic infection.
- Free and viral chromosome-bound simian virus 40 T antigen: changes in reactivity of specific antigenic determinants during lytic infection.
- Role of adenovirus type 2 early region 4 in the early-to-late switch during productive infection.