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. 1992 Oct;12(10):4279–4287. doi: 10.1128/mcb.12.10.4279

The spliceosome assembly pathway in mammalian extracts.

S F Jamison 1, A Crow 1, M A Garcia-Blanco 1
PMCID: PMC360351  PMID: 1383687

Abstract

A mammalian splicing commitment complex was functionally defined by using a template commitment assay. This complex was partially purified and shown to be a required intermediate for complex A formation. The productive formation of this commitment complex required both splice sites and the polypyrimidine tract. U1 small nuclear ribonucleoprotein (snRNP) was the only spliceosomal U snRNP required for this formation. A protein factor, very likely U2AF, is probably involved in the formation of the splicing commitment complex. From the kinetics of appearance of complex A and complex B, it was previously postulated that complex A represents a functional intermediate in spliceosome assembly. Complex A was partially purified and shown to be a required intermediate for complex B (spliceosome) formation. Thus, a spliceosome pathway is for the first time supported by direct biochemical evidence: RNA+U1 snRNP+?U2 auxiliary factor+?Y----CC+U2 snRNP+Z----A+U4/6,5 snRNPs+ beta----B.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Barabino S. M., Blencowe B. J., Ryder U., Sproat B. S., Lamond A. I. Targeted snRNP depletion reveals an additional role for mammalian U1 snRNP in spliceosome assembly. Cell. 1990 Oct 19;63(2):293–302. doi: 10.1016/0092-8674(90)90162-8. [DOI] [PubMed] [Google Scholar]
  2. Bindereif A., Green M. R. An ordered pathway of snRNP binding during mammalian pre-mRNA splicing complex assembly. EMBO J. 1987 Aug;6(8):2415–2424. doi: 10.1002/j.1460-2075.1987.tb02520.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Black D. L., Chabot B., Steitz J. A. U2 as well as U1 small nuclear ribonucleoproteins are involved in premessenger RNA splicing. Cell. 1985 Oct;42(3):737–750. doi: 10.1016/0092-8674(85)90270-3. [DOI] [PubMed] [Google Scholar]
  4. Black D. L., Steitz J. A. Pre-mRNA splicing in vitro requires intact U4/U6 small nuclear ribonucleoprotein. Cell. 1986 Aug 29;46(5):697–704. doi: 10.1016/0092-8674(86)90345-4. [DOI] [PubMed] [Google Scholar]
  5. Blencowe B. J., Sproat B. S., Ryder U., Barabino S., Lamond A. I. Antisense probing of the human U4/U6 snRNP with biotinylated 2'-OMe RNA oligonucleotides. Cell. 1989 Nov 3;59(3):531–539. doi: 10.1016/0092-8674(89)90036-6. [DOI] [PubMed] [Google Scholar]
  6. Bothwell A. L., Ballard D. W., Philbrick W. M., Lindwall G., Maher S. E., Bridgett M. M., Jamison S. F., Garcia-Blanco M. A. Murine polypyrimidine tract binding protein. Purification, cloning, and mapping of the RNA binding domain. J Biol Chem. 1991 Dec 25;266(36):24657–24663. [PubMed] [Google Scholar]
  7. Cheng S. C., Abelson J. Spliceosome assembly in yeast. Genes Dev. 1987 Nov;1(9):1014–1027. doi: 10.1101/gad.1.9.1014. [DOI] [PubMed] [Google Scholar]
  8. Choi Y. D., Grabowski P. J., Sharp P. A., Dreyfuss G. Heterogeneous nuclear ribonucleoproteins: role in RNA splicing. Science. 1986 Mar 28;231(4745):1534–1539. doi: 10.1126/science.3952495. [DOI] [PubMed] [Google Scholar]
  9. 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]
  10. Frendewey D., Keller W. Stepwise assembly of a pre-mRNA splicing complex requires U-snRNPs and specific intron sequences. Cell. 1985 Aug;42(1):355–367. doi: 10.1016/s0092-8674(85)80131-8. [DOI] [PubMed] [Google Scholar]
  11. García-Blanco M. A., Jamison S. F., Sharp P. A. Identification and purification of a 62,000-dalton protein that binds specifically to the polypyrimidine tract of introns. Genes Dev. 1989 Dec;3(12A):1874–1886. doi: 10.1101/gad.3.12a.1874. [DOI] [PubMed] [Google Scholar]
  12. Ge H., Zuo P., Manley J. L. Primary structure of the human splicing factor ASF reveals similarities with Drosophila regulators. Cell. 1991 Jul 26;66(2):373–382. doi: 10.1016/0092-8674(91)90626-a. [DOI] [PubMed] [Google Scholar]
  13. Gil A., Sharp P. A., Jamison S. F., Garcia-Blanco M. A. Characterization of cDNAs encoding the polypyrimidine tract-binding protein. Genes Dev. 1991 Jul;5(7):1224–1236. doi: 10.1101/gad.5.7.1224. [DOI] [PubMed] [Google Scholar]
  14. Grabowski P. J., Seiler S. R., Sharp P. A. A multicomponent complex is involved in the splicing of messenger RNA precursors. Cell. 1985 Aug;42(1):345–353. doi: 10.1016/s0092-8674(85)80130-6. [DOI] [PubMed] [Google Scholar]
  15. Grabowski P. J., Sharp P. A. Affinity chromatography of splicing complexes: U2, U5, and U4 + U6 small nuclear ribonucleoprotein particles in the spliceosome. Science. 1986 Sep 19;233(4770):1294–1299. doi: 10.1126/science.3638792. [DOI] [PubMed] [Google Scholar]
  16. Green M. R. Biochemical mechanisms of constitutive and regulated pre-mRNA splicing. Annu Rev Cell Biol. 1991;7:559–599. doi: 10.1146/annurev.cb.07.110191.003015. [DOI] [PubMed] [Google Scholar]
  17. Helfman D. M., Roscigno R. F., Mulligan G. J., Finn L. A., Weber K. S. Identification of two distinct intron elements involved in alternative splicing of beta-tropomyosin pre-mRNA. Genes Dev. 1990 Jan;4(1):98–110. doi: 10.1101/gad.4.1.98. [DOI] [PubMed] [Google Scholar]
  18. Konarska M. M., Sharp P. A. Electrophoretic separation of complexes involved in the splicing of precursors to mRNAs. Cell. 1986 Sep 12;46(6):845–855. doi: 10.1016/0092-8674(86)90066-8. [DOI] [PubMed] [Google Scholar]
  19. Konarska M. M., Sharp P. A. Interactions between small nuclear ribonucleoprotein particles in formation of spliceosomes. Cell. 1987 Jun 19;49(6):763–774. doi: 10.1016/0092-8674(87)90614-3. [DOI] [PubMed] [Google Scholar]
  20. Krainer A. R., Conway G. C., Kozak D. Purification and characterization of pre-mRNA splicing factor SF2 from HeLa cells. Genes Dev. 1990 Jul;4(7):1158–1171. doi: 10.1101/gad.4.7.1158. [DOI] [PubMed] [Google Scholar]
  21. Krainer A. R., Mayeda A., Kozak D., Binns G. Functional expression of cloned human splicing factor SF2: homology to RNA-binding proteins, U1 70K, and Drosophila splicing regulators. Cell. 1991 Jul 26;66(2):383–394. doi: 10.1016/0092-8674(91)90627-b. [DOI] [PubMed] [Google Scholar]
  22. Krämer A. Presplicing complex formation requires two proteins and U2 snRNP. Genes Dev. 1988 Sep;2(9):1155–1167. doi: 10.1101/gad.2.9.1155. [DOI] [PubMed] [Google Scholar]
  23. Lamm G. M., Blencowe B. J., Sproat B. S., Iribarren A. M., Ryder U., Lamond A. I. Antisense probes containing 2-aminoadenosine allow efficient depletion of U5 snRNP from HeLa splicing extracts. Nucleic Acids Res. 1991 Jun 25;19(12):3193–3198. doi: 10.1093/nar/19.12.3193. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Lamond A. I., Konarska M. M., Sharp P. A. A mutational analysis of spliceosome assembly: evidence for splice site collaboration during spliceosome formation. Genes Dev. 1987 Aug;1(6):532–543. doi: 10.1101/gad.1.6.532. [DOI] [PubMed] [Google Scholar]
  25. Legrain P., Seraphin B., Rosbash M. Early commitment of yeast pre-mRNA to the spliceosome pathway. Mol Cell Biol. 1988 Sep;8(9):3755–3760. doi: 10.1128/mcb.8.9.3755. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Lossky M., Anderson G. J., Jackson S. P., Beggs J. Identification of a yeast snRNP protein and detection of snRNP-snRNP interactions. Cell. 1987 Dec 24;51(6):1019–1026. doi: 10.1016/0092-8674(87)90588-5. [DOI] [PubMed] [Google Scholar]
  27. 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]
  28. Michaud S., Reed R. An ATP-independent complex commits pre-mRNA to the mammalian spliceosome assembly pathway. Genes Dev. 1991 Dec;5(12B):2534–2546. doi: 10.1101/gad.5.12b.2534. [DOI] [PubMed] [Google Scholar]
  29. Patton J. G., Mayer S. A., Tempst P., Nadal-Ginard B. Characterization and molecular cloning of polypyrimidine tract-binding protein: a component of a complex necessary for pre-mRNA splicing. Genes Dev. 1991 Jul;5(7):1237–1251. doi: 10.1101/gad.5.7.1237. [DOI] [PubMed] [Google Scholar]
  30. Pikielny C. W., Rymond B. C., Rosbash M. Electrophoresis of ribonucleoproteins reveals an ordered assembly pathway of yeast splicing complexes. 1986 Nov 27-Dec 3Nature. 324(6095):341–345. doi: 10.1038/324341a0. [DOI] [PubMed] [Google Scholar]
  31. Reed R., Maniatis T. The role of the mammalian branchpoint sequence in pre-mRNA splicing. Genes Dev. 1988 Oct;2(10):1268–1276. doi: 10.1101/gad.2.10.1268. [DOI] [PubMed] [Google Scholar]
  32. Reed R. Protein composition of mammalian spliceosomes assembled in vitro. Proc Natl Acad Sci U S A. 1990 Oct;87(20):8031–8035. doi: 10.1073/pnas.87.20.8031. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Reed R. The organization of 3' splice-site sequences in mammalian introns. Genes Dev. 1989 Dec;3(12B):2113–2123. doi: 10.1101/gad.3.12b.2113. [DOI] [PubMed] [Google Scholar]
  34. Ruby S. W., Abelson J. An early hierarchic role of U1 small nuclear ribonucleoprotein in spliceosome assembly. Science. 1988 Nov 18;242(4881):1028–1035. doi: 10.1126/science.2973660. [DOI] [PubMed] [Google Scholar]
  35. 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]
  36. Seraphin B., Rosbash M. Identification of functional U1 snRNA-pre-mRNA complexes committed to spliceosome assembly and splicing. Cell. 1989 Oct 20;59(2):349–358. doi: 10.1016/0092-8674(89)90296-1. [DOI] [PubMed] [Google Scholar]
  37. Smith C. W., Porro E. B., Patton J. G., Nadal-Ginard B. Scanning from an independently specified branch point defines the 3' splice site of mammalian introns. Nature. 1989 Nov 16;342(6247):243–247. doi: 10.1038/342243a0. [DOI] [PubMed] [Google Scholar]
  38. Swanson M. S., Dreyfuss G. RNA binding specificity of hnRNP proteins: a subset bind to the 3' end of introns. EMBO J. 1988 Nov;7(11):3519–3529. doi: 10.1002/j.1460-2075.1988.tb03228.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Séraphin B., Abovich N., Rosbash M. Genetic depletion indicates a late role for U5 snRNP during in vitro spliceosome assembly. Nucleic Acids Res. 1991 Jul 25;19(14):3857–3860. doi: 10.1093/nar/19.14.3857. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Séraphin B., Rosbash M. The yeast branchpoint sequence is not required for the formation of a stable U1 snRNA-pre-mRNA complex and is recognized in the absence of U2 snRNA. EMBO J. 1991 May;10(5):1209–1216. doi: 10.1002/j.1460-2075.1991.tb08062.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Zamore P. D., Green M. R. Identification, purification, and biochemical characterization of U2 small nuclear ribonucleoprotein auxiliary factor. Proc Natl Acad Sci U S A. 1989 Dec;86(23):9243–9247. doi: 10.1073/pnas.86.23.9243. [DOI] [PMC free article] [PubMed] [Google Scholar]

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