Abstract:
:We present here direct evidence for the preservation of a transcriptional initiation sequence in a eukaryotic rRNA precursor: the 5'-end group for precursor to 17S rRNA (p17S RNA) from Dictyostelium discoideum is identified as the triphosphate residue pppA-. We also show that mature 5S RNA form Dictyostelium bears a different triphosphate residue, pppG-. In contrast, we find no evidence for more than one phosphate at the 5' end of the 25S rRNA precursor (p25S RNA). These observations indicate that synthesis of the large ribosomal RNAs of Dictyostelium begins with the 5'-terminal sequence of the p17S RNA, and that 5S RNA transcription must be initiated independently, despite the close association of the 5S and rRNA coding segments.
journal_name
Proc Natl Acad Sci U S Aauthors
Batts-Young B,Lodish HFdoi
10.1073/pnas.75.2.740subject
Has Abstractpub_date
1978-02-01 00:00:00pages
740-4issue
2eissn
0027-8424issn
1091-6490journal_volume
75pub_type
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