Abstract
Although the U1 small nuclear ribonucleoprotein particle (snRNP) was the first mRNA-splicing cofactor to be identified, the manner in which it functions in splicing is not precisely understood. Among the information required to understand how U1 snRNP participates in splicing, it will be necessary to know its structure. Here we describe the in vitro reconstitution of a particle that possesses the properties of native U1 snRNP. 32P-labeled U1 RNA was transcribed from an SP6 promoter-human U1 gene clone and incubated in a HeLa S100 fraction. A U1 particle formed which displayed the same sedimentation coefficient (approximately 10S) and buoyant density (1.40 g/cm3) as native U1 snRNP. The latter value reflects the ability to withstand isopycnic banding in Cs2SO4 without prior fixation, a property shared by native U1 snRNP. The reconstituted U1 particle reacted with both the Sm and RNP monoclonal antibodies, showing that these two classes of snRNP proteins were present. Moreover, the reconstituted U1 snRNP particle was found to display the characteristic Mg2+ switch of nuclease sensitivity previously described for native U1 snRNP: an open, nuclease-sensitive conformation at a low Mg2+ concentration (3 mM) and a more compact, nuclease-resistant organization at a higher concentration (15 mM). The majority of the U1 RNA in the reconstituted particle did not contain hypermethylated caps, pseudouridine, or ribose 2-O-methylation, showing that these enigmatic posttranscriptional modifications are not essential for reconstitution of the U1 snRNP particle. The extreme 3' end (18 nucleotides) of U1 RNA was required for reconstitution, but loop II (nucleotides 64 to 77) was not. Interestingly, the 5' end (15 nucleotides) of U1 RNA that recognizes pre-mRNA 5' splice sites was not required for U1 snRNP reconstruction.
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- Billings P. B., Allen R. W., Jensen F. C., Hoch S. O. Anti-RNP monoclonal antibodies derived from a mouse strain with lupus-like autoimmunity. J Immunol. 1982 Mar;128(3):1176–1180. [PubMed] [Google Scholar]
- Billings P. B., Hoch S. O. Characterization of U small nuclear RNA-associated proteins. J Biol Chem. 1984 Oct 25;259(20):12850–12856. [PubMed] [Google Scholar]
- Bringmann P., Lührmann R. Purification of the individual snRNPs U1, U2, U5 and U4/U6 from HeLa cells and characterization of their protein constituents. EMBO J. 1986 Dec 20;5(13):3509–3516. doi: 10.1002/j.1460-2075.1986.tb04676.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Calvet J. P., Pederson T. Base-pairing interactions between small nuclear RNAs and nuclear RNA precursors as revealed by psoralen cross-linking in vivo. Cell. 1981 Nov;26(3 Pt 1):363–370. doi: 10.1016/0092-8674(81)90205-1. [DOI] [PubMed] [Google Scholar]
- Chae C. B., Patton J. R. Chicken reticulocyte polysomal messenger RNA-protein complex: absence of bound proteins in most of the coding region of beta globin mRNA. Nucleic Acids Res. 1984 Jul 25;12(14):5693–5706. doi: 10.1093/nar/12.14.5693. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dignam J. D., Lebovitz R. M., Roeder R. G. Accurate transcription initiation by RNA polymerase II in a soluble extract from isolated mammalian nuclei. Nucleic Acids Res. 1983 Mar 11;11(5):1475–1489. doi: 10.1093/nar/11.5.1475. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Economidis I. V., Pederson T. In vitro assembly of a pre-messenger ribonucleoprotein. Proc Natl Acad Sci U S A. 1983 Jul;80(14):4296–4300. doi: 10.1073/pnas.80.14.4296. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fisher D. E., Conner G. E., Reeves W. H., Wisniewolski R., Blobel G. Small nuclear ribonucleoprotein particle assembly in vivo: demonstration of a 6S RNA-free core precursor and posttranslational modification. Cell. 1985 Oct;42(3):751–758. doi: 10.1016/0092-8674(85)90271-5. [DOI] [PubMed] [Google Scholar]
- Hardy S. F., Grabowski P. J., Padgett R. A., Sharp P. A. Cofactor requirements of splicing of purified messenger RNA precursors. Nature. 1984 Mar 22;308(5957):375–377. doi: 10.1038/308375a0. [DOI] [PubMed] [Google Scholar]
- Hinterberger M., Pettersson I., Steitz J. A. Isolation of small nuclear ribonucleoproteins containing U1, U2, U4, U5, and U6 RNAs. J Biol Chem. 1983 Feb 25;258(4):2604–2613. [PubMed] [Google Scholar]
- Kinlaw C. S., Robberson B. L., Berget S. M. Fractionation and characterization of human small nuclear ribonucleoproteins containing U1 and U2 RNAs. J Biol Chem. 1983 Jun 10;258(11):7181–7189. [PubMed] [Google Scholar]
- Kleinschmidt A. M., Pederson T. Accurate and efficient 3' processing of U2 small nuclear RNA precursor in a fractionated cytoplasmic extract. Mol Cell Biol. 1987 Sep;7(9):3131–3137. doi: 10.1128/mcb.7.9.3131. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Krämer A., Keller W., Appel B., Lührmann R. The 5' terminus of the RNA moiety of U1 small nuclear ribonucleoprotein particles is required for the splicing of messenger RNA precursors. Cell. 1984 Aug;38(1):299–307. doi: 10.1016/0092-8674(84)90551-8. [DOI] [PubMed] [Google Scholar]
- Lelay-Taha M. N., Reveillaud I., Sri-Widada J., Brunel C., Jeanteur P. RNA-protein organization of U1, U5 and U4-U6 small nuclear ribonucleoproteins in HeLa cells. J Mol Biol. 1986 Jun 5;189(3):519–532. doi: 10.1016/0022-2836(86)90321-9. [DOI] [PubMed] [Google Scholar]
- Lerner E. A., Lerner M. R., Janeway C. A., Jr, Steitz J. A. Monoclonal antibodies to nucleic acid-containing cellular constituents: probes for molecular biology and autoimmune disease. Proc Natl Acad Sci U S A. 1981 May;78(5):2737–2741. doi: 10.1073/pnas.78.5.2737. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lerner M. R., Boyle J. A., Mount S. M., Wolin S. L., Steitz J. A. Are snRNPs involved in splicing? Nature. 1980 Jan 10;283(5743):220–224. doi: 10.1038/283220a0. [DOI] [PubMed] [Google Scholar]
- Liautard J. P., Sri-Widada J., Brunel C., Jeanteur P. Structural organization of ribonucleoproteins containing small nuclear RNAs from HeLa cells. Proteins interact closely with a similar structural domain of U1, U2, U4 and U5 small nuclear RNAs. J Mol Biol. 1982 Dec 15;162(3):623–643. doi: 10.1016/0022-2836(82)90392-8. [DOI] [PubMed] [Google Scholar]
- Lin W. L., Pederson T. Ribonucleoprotein organization of eukaryotic RNA. XXXI. Structure of the U1 small nuclear ribonucleoprotein. J Mol Biol. 1984 Dec 25;180(4):947–960. doi: 10.1016/0022-2836(84)90265-1. [DOI] [PubMed] [Google Scholar]
- Madore S. J., Wieben E. D., Kunkel G. R., Pederson T. Precursors of U4 small nuclear RNA. J Cell Biol. 1984 Sep;99(3):1140–1144. doi: 10.1083/jcb.99.3.1140. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Madore S. J., Wieben E. D., Pederson T. Intracellular site of U1 small nuclear RNA processing and ribonucleoprotein assembly. J Cell Biol. 1984 Jan;98(1):188–192. doi: 10.1083/jcb.98.1.188. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maniatis T., Reed R. The role of small nuclear ribonucleoprotein particles in pre-mRNA splicing. Nature. 1987 Feb 19;325(6106):673–678. doi: 10.1038/325673a0. [DOI] [PubMed] [Google Scholar]
- Manser T., Gesteland R. F. Human U1 loci: genes for human U1 RNA have dramatically similar genomic environments. Cell. 1982 May;29(1):257–264. doi: 10.1016/0092-8674(82)90110-6. [DOI] [PubMed] [Google Scholar]
- Mattaj I. W., De Robertis E. M. Nuclear segregation of U2 snRNA requires binding of specific snRNP proteins. Cell. 1985 Jan;40(1):111–118. doi: 10.1016/0092-8674(85)90314-9. [DOI] [PubMed] [Google Scholar]
- Maxam A. M., Gilbert W. Sequencing end-labeled DNA with base-specific chemical cleavages. Methods Enzymol. 1980;65(1):499–560. doi: 10.1016/s0076-6879(80)65059-9. [DOI] [PubMed] [Google Scholar]
- Mayrand S., Pederson T. Nuclear ribonucleoprotein particles probed in living cells. Proc Natl Acad Sci U S A. 1981 Apr;78(4):2208–2212. doi: 10.1073/pnas.78.4.2208. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Melton D. A., Krieg P. A., Rebagliati M. R., Maniatis T., Zinn K., Green M. R. Efficient in vitro synthesis of biologically active RNA and RNA hybridization probes from plasmids containing a bacteriophage SP6 promoter. Nucleic Acids Res. 1984 Sep 25;12(18):7035–7056. doi: 10.1093/nar/12.18.7035. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Patton J. R., Chae C. B. A method for isolation of a large amount of a single-stranded DNA fragment. Anal Biochem. 1982 Oct;126(1):231–234. doi: 10.1016/0003-2697(82)90134-8. [DOI] [PubMed] [Google Scholar]
- Patton J. R., Chae C. B. A method for mapping RNA initiation, termination, splice, and protein binding sites. Ribosome binding sites on beta-globin messenger RNA. J Biol Chem. 1983 Mar 25;258(6):3991–3995. [PubMed] [Google Scholar]
- Patton J. R., Chae C. B. Specific regions of the intervening sequences of beta-globin RNA are resistant to nuclease in 50S heterogeneous nuclear RNA-protein complexes. Proc Natl Acad Sci U S A. 1985 Dec;82(24):8414–8418. doi: 10.1073/pnas.82.24.8414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pettersson I., Hinterberger M., Mimori T., Gottlieb E., Steitz J. A. The structure of mammalian small nuclear ribonucleoproteins. Identification of multiple protein components reactive with anti-(U1)ribonucleoprotein and anti-Sm autoantibodies. J Biol Chem. 1984 May 10;259(9):5907–5914. [PubMed] [Google Scholar]
- Reddy R. Compilation of small RNA sequences. Nucleic Acids Res. 1985;13 (Suppl):r155–r163. doi: 10.1093/nar/13.suppl.r155. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reveillaud I., Lelay-Taha M. N., Sri-Widada J., Brunel C., Jeanteur P. Mg2+ induces a sharp and reversible transition in U1 and U2 small nuclear ribonucleoprotein configurations. Mol Cell Biol. 1984 Sep;4(9):1890–1899. doi: 10.1128/mcb.4.9.1890. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Silberklang M., Gillum A. M., RajBhandary U. L. Use of in vitro 32P labeling in the sequence analysis of nonradioactive tRNAs. Methods Enzymol. 1979;59:58–109. doi: 10.1016/0076-6879(79)59072-7. [DOI] [PubMed] [Google Scholar]
- Theissen H., Etzerodt M., Reuter R., Schneider C., Lottspeich F., Argos P., Lührmann R., Philipson L. Cloning of the human cDNA for the U1 RNA-associated 70K protein. EMBO J. 1986 Dec 1;5(12):3209–3217. doi: 10.1002/j.1460-2075.1986.tb04631.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wieben E. D., Madore S. J., Pederson T. Protein binding sites are conserved in U1 small nuclear RNA from insects and mammals. Proc Natl Acad Sci U S A. 1983 Mar;80(5):1217–1220. doi: 10.1073/pnas.80.5.1217. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wieben E. D., Madore S. J., Pederson T. U1 small nuclear ribonucleoprotein studied by in vitro assembly. J Cell Biol. 1983 Jun;96(6):1751–1755. doi: 10.1083/jcb.96.6.1751. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wieben E. D., Nenninger J. M., Pederson T. Ribonucleoprotein organization of eukaryotic RNA. XXXII. U2 small nuclear RNA precursors and their accurate 3' processing in vitro as ribonucleoprotein particles. J Mol Biol. 1985 May 5;183(1):69–78. doi: 10.1016/0022-2836(85)90281-5. [DOI] [PubMed] [Google Scholar]
- Wieben E. D., Pederson T. Small nuclear ribonucleoproteins of Drosophila: identification of U1 RNA-associated proteins and their behavior during heat shock. Mol Cell Biol. 1982 Aug;2(8):914–920. doi: 10.1128/mcb.2.8.914. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wieben E. D., Rohleder A. M., Nenninger J. M., Pederson T. cDNA cloning of a human autoimmune nuclear ribonucleoprotein antigen. Proc Natl Acad Sci U S A. 1985 Dec;82(23):7914–7918. doi: 10.1073/pnas.82.23.7914. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhuang Y., Weiner A. M. A compensatory base change in U1 snRNA suppresses a 5' splice site mutation. Cell. 1986 Sep 12;46(6):827–835. doi: 10.1016/0092-8674(86)90064-4. [DOI] [PubMed] [Google Scholar]





