Nucleic Acids Research, 1991, Vol. 19, No. 11 3011-3017
© 1991
MOLECULAR BIOLOGY |
Splice site requirement for the efficient accumulation of polyoma virus late mRNAs
Department of Microbiology, University of Connecticut Health Center Farmington, CT 06030, USA
*To whom correspondence should be addressed
Received February 8, 1991. Revised April 30, 1991. Accepted April 30, 1991.
Polyoma virus late nuclear primary transcripts are giant and heterogeneous, containing tandem repeats of the late strand of the circular viral genome. Late pre-mRNA processing involves the splicing of noncoding leader exons to each other (removing genome-length introns), with the joining of the last leader to a coding body exon. We have constructed a number of mutants blocked only in leader-leader splicing, or blocked in both leader-leader and leader-body splicing. We examined the accumulation of both nuclear and cytoplasmic late-strand RNAs in NIH3T3 cells. Consistent with our previous results, mutants lacking the 3' splice site of the late leader (leader-leader splicing blocked) showed a 1020 fold defect in late RNA accumulation. Mutants which lacked the leader 5' splice site (leader-body splicing blocked) had a more profound defect, exhibiting virtually no late-strand cytoplasmic or nuclear RNA. This result was unexpected as a substantial proportion of wild type late cytoplasmic messages are unspliced. A mutant with no intron, but having functional 3' and 5' splice sites bordering the leader exon, is capable of producing large amounts of unspliced late mRNA. This demonstrates that an excisable intron is not a requirement for late mRNA accumulation. The accumulation of polyoma late mRNAs requires the presence of leader exons bordered by functional 3' and 5' splice sites, whether or not these sites are used during pre-mRNA processing.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
M. Kumar and G. G. Carmichael Nuclear antisense RNA induces extensive adenosine modifications and nuclear retention of target transcripts PNAS, April 15, 1997; 94(8): 3542 - 3547. [Abstract] [Full Text] [PDF] |
||||
![]() |
R M Sandri-Goldin and G E Mendoza A herpesvirus regulatory protein appears to act post-transcriptionally by affecting mRNA processing. Genes & Dev., May 1, 1992; 6(5): 848 - 863. [Abstract] [PDF] |
||||

