Abstract
Ribosomal RNA precursors and mature 28S ribosomal RNA from HeLa cells display a highly reproducible secondary structure of hairpin loops after they are spread and examined in an electron microscope. This structure was used to map the linear arrangement of these molecules. Partial digestion with 3′-exonuclease from ascites cell nuclei established that the 28S RNA region is located at the 5′-end of the 45S precursor. A spacer sequence follows the 28S region. This is followed by the 18S RNA region, and by another spacer sequence at the 3′-end. The 41S RNA contains both 18S and 28S regions. The 32S RNA contains only 28S RNA plus spacer, and the 20S RNA contains only 18S RNA plus spacer. Several minor nucleolar RNA components were also mapped with respect to the 45S RNA. These experiments lead to a more detailed processing pathway for HeLa ribosomal RNA which is in good agreement with earlier work.
Keywords: electron microscopy, 45S RNA, exonuclease, nucleolar RNA
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- Boedtker H. Dependence of the sedimentation coefficient on molecular weight of RNA after reaction with formaldehyde. J Mol Biol. 1968 Jul 14;35(1):61–70. doi: 10.1016/s0022-2836(68)80036-1. [DOI] [PubMed] [Google Scholar]
- Choi Y. C., Busch H. Structural analysis of nucleolar precursors of ribosomal ribonucleic acid. Studies on the 5'-terminal and alkali-resistant dinucleotides of nucleolar high molecular weight ribonucleic acid. J Biol Chem. 1970 Apr 25;245(8):1954–1961. [PubMed] [Google Scholar]
- Delius H., Westphal H., Axelrod N. Length measurements of RNA synthesized in vitro by Escherichia coli RNA polymerase. J Mol Biol. 1973 Mar 15;74(4):677–687. doi: 10.1016/0022-2836(73)90056-9. [DOI] [PubMed] [Google Scholar]
- Hecht R. M., Birnstiel M. L. Integrity of the DNA template, a prerequisite for the faithful transcription of Xenopus rDNA in vitro. Eur J Biochem. 1972 Sep 25;29(3):489–499. doi: 10.1111/j.1432-1033.1972.tb02013.x. [DOI] [PubMed] [Google Scholar]
- Lazarus H. M., Sporin M. B. Purification and properties of a nuclear exoribonuclease from Ehrlich ascites tumor cells. Proc Natl Acad Sci U S A. 1967 May;57(5):1386–1393. doi: 10.1073/pnas.57.5.1386. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maden B. E., Salim M., Summers D. F. Maturation pathway for ribosomal RNA in the Hela cell nucleolus. Nat New Biol. 1972 May 3;237(70):5–9. doi: 10.1038/newbio237005a0. [DOI] [PubMed] [Google Scholar]
- Perry R. P., Kelley D. E. The production of ribosomal RNA from high molecular weight precursors. 3. Hydrolysis of pre-ribosomal and ribosomal RNA by a 3'-OH specific exoribonuclease. J Mol Biol. 1972 Sep 28;70(2):265–279. doi: 10.1016/0022-2836(72)90538-4. [DOI] [PubMed] [Google Scholar]
- Reeder R. H., Brown D. D. Transcription of the ribosomal RNA genes of an amphibian by the RNA polymerase of a bacterium. J Mol Biol. 1970 Jul 28;51(2):361–377. doi: 10.1016/0022-2836(70)90148-8. [DOI] [PubMed] [Google Scholar]
- Robberson D., Aloni Y., Attardi G., Davidson N. Expression of the mitochondrial genome in HeLa cells. VI. Size determination of mitochondrial ribosomal RNA by electron microscopy. J Mol Biol. 1971 Sep 28;60(3):473–484. doi: 10.1016/0022-2836(71)90182-3. [DOI] [PubMed] [Google Scholar]
- Stanley W. M., Jr, Bock R. M. Isolation and physical properties of the ribosomal ribonucleic acid of Escherichia coli. Biochemistry. 1965 Jul;4(7):1302–1311. doi: 10.1021/bi00883a014. [DOI] [PubMed] [Google Scholar]
- Weinberg R. A., Loening U., Willems M., Penman S. Acrylamide gel electrophoresis of HeLa cell nucleolar RNA. Proc Natl Acad Sci U S A. 1967 Sep;58(3):1088–1095. doi: 10.1073/pnas.58.3.1088. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weinberg R. A., Penman S. Processing of 45 s nucleolar RNA. J Mol Biol. 1970 Jan 28;47(2):169–178. doi: 10.1016/0022-2836(70)90337-2. [DOI] [PubMed] [Google Scholar]
- Wu M., Davidson N. Secondary structure in transfer RNA genes. J Mol Biol. 1973 Jun 25;78(1):35–41. doi: 10.1016/0022-2836(73)90426-9. [DOI] [PubMed] [Google Scholar]