title: Poly(A) polymerase activity and RNA polyadenylation in Streptomyces coelicolor A3(2).
abstract: The Streptomyces coelicolor genome sequence was searched for open reading frames (ORFs) similar to Escherichia coli poly(A) polymerase I, revealing an ORF with 36% amino acid sequence identity to that protein. Mycelial extracts prepared from S. coelicolor cultures incorporated radioactive ATP into an acid-insoluble form, and some of the products of this incorporation had the properties expected of poly(A). [3H]-uridine and [3H]-adenosine were used to label the RNA in S. coelicolor cultures of different ages, and total RNA was fractionated by oligo dT cellulose chromatography. Approximately 3% of the total uridine-labelled RNA and 11% of the adenosine-labelled RNA were retained by the oligo dT cellulose columns. Enzymatic digestion of the retained RNA supported the conclusion that a significant fraction of the adenosine label was present in 3'-poly(A) chains. Measurement of poly(A) tail lengths by end labelling of total RNA and RNase digestion revealed a maximum length of approximately 18 residues. Radioactive cDNA prepared from the RNA fraction retained by oligo dT cellulose hybridized to the 16S and 23S genes from a streptomycete ribosomal RNA operon but not to the 5S gene. Reverse transcription-polymerase chain reaction (RT-PCR) revealed the presence of mRNAs in the RNA fraction retained by oligo dT cellulose.
authors.affiliation: Department of Biology, Emory University, Atlanta, GA 30322, USA.
authors.forename: P
authors.initials: P
authors.lastname: Bralley
authors.forename: G H
authors.initials: GH
authors.lastname: Jones
mesh_terms: D000595:Amino Acid Sequence; D015139:Blotting, Southern; D029968:Escherichia coli Proteins; D008969:Molecular Sequence Data; D009876:Operon; D011061:Poly A / Q000737:chemistry / Q000378:metabolism; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics* / Q000378:metabolism*; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000302:isolation & purification / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D011061:Poly A; D011062:Polynucleotide Adenylyltransferase; C063643:pcnB protein, E coli