Characterization of unstable poly (A)-RNA in Caulobacter crescentus.
A significant amount of poly(A)-RNA in Caulobacter crescentus is located on polysomes and the size distribution of this polysomal poly(A)-RNA is small compared to the total pulse-labeled RNA in these cells. These observations suggest that the poly (A)-RNA represents a subset of small messenger RNA molecules. Poly (A)-RNA, and presumably the poly (A) portion of these molecules is extremely unstable: as assayed by binding to oligo (dT)-cellulose the poly (A)-RNA turns over with a chemical half-life of 15--20 s compared to a half-life of approx. 2 min for total cellular messenger RNA. The presence of adenosine in hydrolysates of poly(A) tracts showed that these sequences are located at the 3'-OH end of the RNA. The ratios of AMP/adenosine in the samples confirmed that the length of the A-tracts is approx. 13-17 nucleotides (Ohta, N., Sanders, M. and Newton, A. (1975) Proc. Natl. Acad. Sci. U.S.A. 72, 2343--2346)
D001419:Bacteria / Q000378:metabolism*; D001483:Base Sequence; D002453:Cell Cycle; D008970:Molecular Weight; D011061:Poly A / Q000032:analysis / Q000378:metabolism*; D011132:Polyribosomes / Q000378:metabolism*; D012329:RNA, Bacterial / Q000032:analysis / Q000378:metabolism*; D012265:Ribonucleotides / Q000032:analysis; D013997:Time Factors
D012329:RNA, Bacterial; D012265:Ribonucleotides; D011061:Poly A