3'-end-forming signals of yeast mRNA.
It was previously shown that three distinct but interdependent elements are required for 3' end formation of mRNA in the yeast Saccharomyces cerevisiae: (i) the efficiency element TATATA and related sequences, which function by enhancing the efficiency of positioning elements; (ii) positioning elements, such as TTAAGAAC and AAGAA, which position the poly(A) site; and (iii) the actual site of polyadenylation. In this study, we have shown that several A-rich sequences, including the vertebrate poly(A) signal AATAAA, are also positioning elements. Saturated mutagenesis revealed that optimum sequences of the positioning element were AATAAA and AAAAAA and that this element can tolerate various extents of replacements. However, the GATAAA sequence was completely ineffective. The major cleavage sites determined in vitro corresponded to the major poly(A) sites observed in vivo. Our findings support the assumption that some components of the basic polyadenylation machinery could have been conserved among yeasts, plants, and mammals, although 3' end formation in yeasts is clearly distinct from that of higher eukaryotes.
Guo
Z
Z
Department of Biochemistry, University of Rochester School of Medicine and Dentistry, New York 14642, USA.
Sherman
F
F
D000199:Actins / Q000235:genetics; D000426:Alcohol Dehydrogenase / Q000235:genetics; D000483:Alleles; D001483:Base Sequence; D003574:Cytochrome c Group / Q000235:genetics*; D045304:Cytochromes c; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics; D019204:GTP-Binding Proteins / Q000235:genetics; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011061:Poly A / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics; D012323:RNA Processing, Post-Transcriptional; D012331:RNA, Fungal / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013329:Structure-Activity Relationship; D013728:Terminator Regions, Genetic; D014158:Transcription, Genetic; D020741:rho GTP-Binding Proteins
D000199:Actins; C014059:CYC1 protein, S cerevisiae; D003574:Cytochrome c Group; D017931:DNA Primers; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D011061:Poly A; D045304:Cytochromes c; D000426:Alcohol Dehydrogenase; D011494:Protein Kinases; D019204:GTP-Binding Proteins; C051302:RHO1 protein, S cerevisiae; D020741:rho GTP-Binding Proteins