Abstract
Accurate splicing of precursor mRNAs (pre-mRNAs) requires recognition of the 5' and 3' splice sites at the intron boundaries. Interactions between several splicing factors and the 5' splice site, which occur prior to the first step of splicing, have been well described. In contrast, recognition of the 3' splice site, which is cleaved during the second catalytic step, is poorly understood, particularly in higher eukaryotes. Here, using site-specific photo-crosslinking, we find that the conserved AG dinucleotide at the 3' splice site is contacted specifically by a 70 kDa polypeptide (p70). The p70-3' splice site crosslink has kinetics and biochemical requirements similar to those of splicing, was detected only in the mature spliceosome and occurs subsequent to the first step. Thus, p70 has all the properties expected of a factor that functionally interacts with the 3' splice site during the second step of splicing. Using antisera to various known splicing factors, we find that p70 corresponds to a previously reported 69 kDa protein of unknown function associated with the Sm core domain of spliceosomal small nuclear ribonucleoproteins.
Full Text
The Full Text of this article is available as a PDF (544.1 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Abmayr S. M., Reed R., Maniatis T. Identification of a functional mammalian spliceosome containing unspliced pre-mRNA. Proc Natl Acad Sci U S A. 1988 Oct;85(19):7216–7220. doi: 10.1073/pnas.85.19.7216. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Aebi M., Hornig H., Padgett R. A., Reiser J., Weissmann C. Sequence requirements for splicing of higher eukaryotic nuclear pre-mRNA. Cell. 1986 Nov 21;47(4):555–565. doi: 10.1016/0092-8674(86)90620-3. [DOI] [PubMed] [Google Scholar]
- Brosi R., Gröning K., Behrens S. E., Lührmann R., Krämer A. Interaction of mammalian splicing factor SF3a with U2 snRNP and relation of its 60-kD subunit to yeast PRP9. Science. 1993 Oct 1;262(5130):102–105. doi: 10.1126/science.8211112. [DOI] [PubMed] [Google Scholar]
- Chiara M. D., Gozani O., Bennett M., Champion-Arnaud P., Palandjian L., Reed R. Identification of proteins that interact with exon sequences, splice sites, and the branchpoint sequence during each stage of spliceosome assembly. Mol Cell Biol. 1996 Jul;16(7):3317–3326. doi: 10.1128/mcb.16.7.3317. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frank D., Guthrie C. An essential splicing factor, SLU7, mediates 3' splice site choice in yeast. Genes Dev. 1992 Nov;6(11):2112–2124. doi: 10.1101/gad.6.11.2112. [DOI] [PubMed] [Google Scholar]
- 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]
- Gaur R. K., Valcárcel J., Green M. R. Sequential recognition of the pre-mRNA branch point by U2AF65 and a novel spliceosome-associated 28-kDa protein. RNA. 1995 Jun;1(4):407–417. [PMC free article] [PubMed] [Google Scholar]
- Gozani O., Patton J. G., Reed R. A novel set of spliceosome-associated proteins and the essential splicing factor PSF bind stably to pre-mRNA prior to catalytic step II of the splicing reaction. EMBO J. 1994 Jul 15;13(14):3356–3367. doi: 10.1002/j.1460-2075.1994.tb06638.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hackl W., Fischer U., Lührmann R. A 69-kD protein that associates reversibly with the Sm core domain of several spliceosomal snRNP species. J Cell Biol. 1994 Feb;124(3):261–272. doi: 10.1083/jcb.124.3.261. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kandels-Lewis S., Séraphin B. Involvement of U6 snRNA in 5' splice site selection. Science. 1993 Dec 24;262(5142):2035–2039. doi: 10.1126/science.8266100. [DOI] [PubMed] [Google Scholar]
- Konforti B. B., Koziolkiewicz M. J., Konarska M. M. Disruption of base pairing between the 5' splice site and the 5' end of U1 snRNA is required for spliceosome assembly. Cell. 1993 Dec 3;75(5):863–873. doi: 10.1016/0092-8674(93)90531-t. [DOI] [PubMed] [Google Scholar]
- Krainer A. R., Maniatis T. Multiple factors including the small nuclear ribonucleoproteins U1 and U2 are necessary for pre-mRNA splicing in vitro. Cell. 1985 Oct;42(3):725–736. doi: 10.1016/0092-8674(85)90269-7. [DOI] [PubMed] [Google Scholar]
- Krämer A. The structure and function of proteins involved in mammalian pre-mRNA splicing. Annu Rev Biochem. 1996;65:367–409. doi: 10.1146/annurev.bi.65.070196.002055. [DOI] [PubMed] [Google Scholar]
- 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]
- Lesser C. F., Guthrie C. Mutations in U6 snRNA that alter splice site specificity: implications for the active site. Science. 1993 Dec 24;262(5142):1982–1988. doi: 10.1126/science.8266093. [DOI] [PubMed] [Google Scholar]
- Madhani H. D., Guthrie C. Dynamic RNA-RNA interactions in the spliceosome. Annu Rev Genet. 1994;28:1–26. doi: 10.1146/annurev.ge.28.120194.000245. [DOI] [PubMed] [Google Scholar]
- Milligan J. F., Groebe D. R., Witherell G. W., Uhlenbeck O. C. Oligoribonucleotide synthesis using T7 RNA polymerase and synthetic DNA templates. Nucleic Acids Res. 1987 Nov 11;15(21):8783–8798. doi: 10.1093/nar/15.21.8783. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newman A. J., Lin R. J., Cheng S. C., Abelson J. Molecular consequences of specific intron mutations on yeast mRNA splicing in vivo and in vitro. Cell. 1985 Aug;42(1):335–344. doi: 10.1016/s0092-8674(85)80129-x. [DOI] [PubMed] [Google Scholar]
- Query C. C., Bentley R. C., Keene J. D. A common RNA recognition motif identified within a defined U1 RNA binding domain of the 70K U1 snRNP protein. Cell. 1989 Apr 7;57(1):89–101. doi: 10.1016/0092-8674(89)90175-x. [DOI] [PubMed] [Google Scholar]
- 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]
- Ruskin B., Zamore P. D., Green M. R. A factor, U2AF, is required for U2 snRNP binding and splicing complex assembly. Cell. 1988 Jan 29;52(2):207–219. doi: 10.1016/0092-8674(88)90509-0. [DOI] [PubMed] [Google Scholar]
- Sawa H., Shimura Y. Association of U6 snRNA with the 5'-splice site region of pre-mRNA in the spliceosome. Genes Dev. 1992 Feb;6(2):244–254. doi: 10.1101/gad.6.2.244. [DOI] [PubMed] [Google Scholar]
- Schwer B., Guthrie C. A conformational rearrangement in the spliceosome is dependent on PRP16 and ATP hydrolysis. EMBO J. 1992 Dec;11(13):5033–5039. doi: 10.1002/j.1460-2075.1992.tb05610.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Singh R., Valcárcel J., Green M. R. Distinct binding specificities and functions of higher eukaryotic polypyrimidine tract-binding proteins. Science. 1995 May 26;268(5214):1173–1176. doi: 10.1126/science.7761834. [DOI] [PubMed] [Google Scholar]
- 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]
- Sontheimer E. J., Steitz J. A. The U5 and U6 small nuclear RNAs as active site components of the spliceosome. Science. 1993 Dec 24;262(5142):1989–1996. doi: 10.1126/science.8266094. [DOI] [PubMed] [Google Scholar]
- Staknis D., Reed R. Members of a family of proteins (the RD family) detected by a U1 70K monoclonal antibody are present in spliceosomal complexes. Nucleic Acids Res. 1995 Oct 25;23(20):4081–4086. doi: 10.1093/nar/23.20.4081. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Séraphin B., Rosbash M. Exon mutations uncouple 5' splice site selection from U1 snRNA pairing. Cell. 1990 Nov 2;63(3):619–629. doi: 10.1016/0092-8674(90)90457-p. [DOI] [PubMed] [Google Scholar]
- Tazi J., Alibert C., Temsamani J., Reveillaud I., Cathala G., Brunel C., Jeanteur P. A protein that specifically recognizes the 3' splice site of mammalian pre-mRNA introns is associated with a small nuclear ribonucleoprotein. Cell. 1986 Dec 5;47(5):755–766. doi: 10.1016/0092-8674(86)90518-0. [DOI] [PubMed] [Google Scholar]
- Teigelkamp S., Newman A. J., Beggs J. D. Extensive interactions of PRP8 protein with the 5' and 3' splice sites during splicing suggest a role in stabilization of exon alignment by U5 snRNA. EMBO J. 1995 Jun 1;14(11):2602–2612. doi: 10.1002/j.1460-2075.1995.tb07258.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Teigelkamp S., Whittaker E., Beggs J. D. Interaction of the yeast splicing factor PRP8 with substrate RNA during both steps of splicing. Nucleic Acids Res. 1995 Feb 11;23(3):320–326. doi: 10.1093/nar/23.3.320. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Umen J. G., Guthrie C. A novel role for a U5 snRNP protein in 3' splice site selection. Genes Dev. 1995 Apr 1;9(7):855–868. doi: 10.1101/gad.9.7.855. [DOI] [PubMed] [Google Scholar]
- Umen J. G., Guthrie C. Prp16p, Slu7p, and Prp8p interact with the 3' splice site in two distinct stages during the second catalytic step of pre-mRNA splicing. RNA. 1995 Aug;1(6):584–597. [PMC free article] [PubMed] [Google Scholar]
- Umen J. G., Guthrie C. The second catalytic step of pre-mRNA splicing. RNA. 1995 Nov;1(9):869–885. [PMC free article] [PubMed] [Google Scholar]
- Wassarman D. A., Steitz J. A. Interactions of small nuclear RNA's with precursor messenger RNA during in vitro splicing. Science. 1992 Sep 25;257(5078):1918–1925. doi: 10.1126/science.1411506. [DOI] [PubMed] [Google Scholar]
- Wu J., Manley J. L. Mammalian pre-mRNA branch site selection by U2 snRNP involves base pairing. Genes Dev. 1989 Oct;3(10):1553–1561. doi: 10.1101/gad.3.10.1553. [DOI] [PubMed] [Google Scholar]
- Wyatt J. R., Sontheimer E. J., Steitz J. A. Site-specific cross-linking of mammalian U5 snRNP to the 5' splice site before the first step of pre-mRNA splicing. Genes Dev. 1992 Dec;6(12B):2542–2553. doi: 10.1101/gad.6.12b.2542. [DOI] [PubMed] [Google Scholar]
- Zamore P. D., Green M. R. Biochemical characterization of U2 snRNP auxiliary factor: an essential pre-mRNA splicing factor with a novel intranuclear distribution. EMBO J. 1991 Jan;10(1):207–214. doi: 10.1002/j.1460-2075.1991.tb07937.x. [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]
- Zhuang Y., Weiner A. M. A compensatory base change in human U2 snRNA can suppress a branch site mutation. Genes Dev. 1989 Oct;3(10):1545–1552. doi: 10.1101/gad.3.10.1545. [DOI] [PubMed] [Google Scholar]
- Zhuang Y., Weiner A. M. The conserved dinucleotide AG of the 3' splice site may be recognized twice during in vitro splicing of mammalian mRNA precursors. Gene. 1990 Jun 15;90(2):263–269. doi: 10.1016/0378-1119(90)90189-x. [DOI] [PubMed] [Google Scholar]
- Zillmann M., Zapp M. L., Berget S. M. Gel electrophoretic isolation of splicing complexes containing U1 small nuclear ribonucleoprotein particles. Mol Cell Biol. 1988 Feb;8(2):814–821. doi: 10.1128/mcb.8.2.814. [DOI] [PMC free article] [PubMed] [Google Scholar]