Polyadenylation of rRNA in Saccharomyces cerevisiae
In contrast to mRNAs, rRNAs are transcribed by RNA polymerase I or III and are not believed to be polyadenylated. Here we show that in Saccharomyces cerevisiae, at least a small fraction of rRNAs do have a poly(A) tail. The levels of polyadenylated rRNAs are dramatically increased in strains lacking...
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Published in | Proceedings of the National Academy of Sciences - PNAS Vol. 101; no. 23; pp. 8581 - 8586 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
United States
National Academy of Sciences
08.06.2004
National Acad Sciences |
Subjects | |
Online Access | Get full text |
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Summary: | In contrast to mRNAs, rRNAs are transcribed by RNA polymerase I or III and are not believed to be polyadenylated. Here we show that in Saccharomyces cerevisiae, at least a small fraction of rRNAs do have a poly(A) tail. The levels of polyadenylated rRNAs are dramatically increased in strains lacking the degradation function of Rrp6p, a component of the nuclear exosome. Pap1p, the poly(A) polymerase, is responsible for adenylating the rRNAs despite the fact that the rRNAs do not have a canonical polyadenylation signal. Polyadenylated rRNAs reside mainly within the nucleus and are in turn degraded. For at least one rRNA type, the polyadenylation preferentially occurs on the precursor rather than the mature product. The existence of polyadenylated rRNAs may reflect a quality-control mechanism of rRNA biogenesis. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 To whom correspondence should be addressed. E-mail: fred_sherman@urmc.rochester.edu. Contributed by Fred Sherman, April 26, 2004 Abbreviation: PT, poly(dT)30 primer. |
ISSN: | 0027-8424 1091-6490 |
DOI: | 10.1073/pnas.0402888101 |