Abstract
We describe analyses of the structure and expression of the rat fibronectin gene with particular attention to the 40-kb stretch from the center of the gene which encodes 17 type-III repeating units. Each repeat is precisely separated from its neighbors by introns and most are encoded by pairs of exons. Three repeats are encoded precisely by single exons and two of these (EIIIA and EIIIB) are alternatively spliced in a cell type-specific fashion. A third site of alternative splicing (EIIIB) reported here is similar in expression to the previously described EIIIA segment. Both are excluded from mRNA in liver cells and are, therefore, absent from plasma fibronectin. These two alternative splices, plus a third one (V) reported previously, can occur in all possible combinations giving 12 fibronectin mRNAs from a single gene. These splicing variations account for most but not all of the known fibronectin subunit variants. We report investigations designed to detect other regions of alternative splicing. We also show that the pattern of alternative splicing is somewhat altered on oncogenic transformation.
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Selected References
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- Borsi L., Carnemolla B., Castellani P., Rosellini C., Vecchio D., Allemanni G., Chang S. E., Taylor-Papadimitriou J., Pande H., Zardi L. Monoclonal antibodies in the analysis of fibronectin isoforms generated by alternative splicing of mRNA precursors in normal and transformed human cells. J Cell Biol. 1987 Mar;104(3):595–600. doi: 10.1083/jcb.104.3.595. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Castellani P., Siri A., Rosellini C., Infusini E., Borsi L., Zardi L. Transformed human cells release different fibronectin variants than do normal cells. J Cell Biol. 1986 Nov;103(5):1671–1677. doi: 10.1083/jcb.103.5.1671. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chirgwin J. M., Przybyla A. E., MacDonald R. J., Rutter W. J. Isolation of biologically active ribonucleic acid from sources enriched in ribonuclease. Biochemistry. 1979 Nov 27;18(24):5294–5299. doi: 10.1021/bi00591a005. [DOI] [PubMed] [Google Scholar]
- Craik C. S., Rutter W. J., Fletterick R. Splice junctions: association with variation in protein structure. Science. 1983 Jun 10;220(4602):1125–1129. doi: 10.1126/science.6344214. [DOI] [PubMed] [Google Scholar]
- Hirano H., Yamada Y., Sullivan M., de Crombrugghe B., Pastan I., Yamada K. M. Isolation of genomic DNA clones spanning the entire fibronectin gene. Proc Natl Acad Sci U S A. 1983 Jan;80(1):46–50. doi: 10.1073/pnas.80.1.46. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hynes R. Molecular biology of fibronectin. Annu Rev Cell Biol. 1985;1:67–90. doi: 10.1146/annurev.cb.01.110185.000435. [DOI] [PubMed] [Google Scholar]
- Kornblihtt A. R., Umezawa K., Vibe-Pedersen K., Baralle F. E. Primary structure of human fibronectin: differential splicing may generate at least 10 polypeptides from a single gene. EMBO J. 1985 Jul;4(7):1755–1759. doi: 10.1002/j.1460-2075.1985.tb03847.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kornblihtt A. R., Vibe-Pedersen K., Baralle F. E. Human fibronectin: cell specific alternative mRNA splicing generates polypeptide chains differing in the number of internal repeats. Nucleic Acids Res. 1984 Jul 25;12(14):5853–5868. doi: 10.1093/nar/12.14.5853. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kornblihtt A. R., Vibe-Pedersen K., Baralle F. E. Human fibronectin: molecular cloning evidence for two mRNA species differing by an internal segment coding for a structural domain. EMBO J. 1984 Jan;3(1):221–226. doi: 10.1002/j.1460-2075.1984.tb01787.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matsuura H., Hakomori S. The oncofetal domain of fibronectin defined by monoclonal antibody FDC-6: its presence in fibronectins from fetal and tumor tissues and its absence in those from normal adult tissues and plasma. Proc Natl Acad Sci U S A. 1985 Oct;82(19):6517–6521. doi: 10.1073/pnas.82.19.6517. [DOI] [PMC free article] [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]
- Odermatt E., Tamkun J. W., Hynes R. O. Repeating modular structure of the fibronectin gene: relationship to protein structure and subunit variation. Proc Natl Acad Sci U S A. 1985 Oct;82(19):6571–6575. doi: 10.1073/pnas.82.19.6571. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oldberg A., Ruoslahti E. Evolution of the fibronectin gene. Exon structure of cell attachment domain. J Biol Chem. 1986 Feb 15;261(5):2113–2116. [PubMed] [Google Scholar]
- Paul J. I., Hynes R. O. Multiple fibronectin subunits and their post-translational modifications. J Biol Chem. 1984 Nov 10;259(21):13477–13487. [PubMed] [Google Scholar]
- Paul J. I., Schwarzbauer J. E., Tamkun J. W., Hynes R. O. Cell-type-specific fibronectin subunits generated by alternative splicing. J Biol Chem. 1986 Sep 15;261(26):12258–12265. [PubMed] [Google Scholar]
- Schwarzbauer J. E., Mulligan R. C., Hynes R. O. Efficient and stable expression of recombinant fibronectin polypeptides. Proc Natl Acad Sci U S A. 1987 Feb;84(3):754–758. doi: 10.1073/pnas.84.3.754. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwarzbauer J. E., Paul J. I., Hynes R. O. On the origin of species of fibronectin. Proc Natl Acad Sci U S A. 1985 Mar;82(5):1424–1428. doi: 10.1073/pnas.82.5.1424. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwarzbauer J. E., Tamkun J. W., Lemischka I. R., Hynes R. O. Three different fibronectin mRNAs arise by alternative splicing within the coding region. Cell. 1983 Dec;35(2 Pt 1):421–431. doi: 10.1016/0092-8674(83)90175-7. [DOI] [PubMed] [Google Scholar]
- Sekiguchi K., Klos A. M., Kurachi K., Yoshitake S., Hakomori S. Human liver fibronectin complementary DNAs: identification of two different messenger RNAs possibly encoding the alpha and beta subunits of plasma fibronectin. Biochemistry. 1986 Aug 26;25(17):4936–4941. doi: 10.1021/bi00365a032. [DOI] [PubMed] [Google Scholar]
- Sekiguchi K., Siri A., Zardi L., Hakomori S. Differences in domain structure between human fibronectins isolated from plasma and from culture supernatants of normal and transformed fibroblasts. Studies with domain-specific antibodies. J Biol Chem. 1985 Apr 25;260(8):5105–5114. [PubMed] [Google Scholar]
- Skorstengaard K., Jensen M. S., Sahl P., Petersen T. E., Magnusson S. Complete primary structure of bovine plasma fibronectin. Eur J Biochem. 1986 Dec 1;161(2):441–453. doi: 10.1111/j.1432-1033.1986.tb10464.x. [DOI] [PubMed] [Google Scholar]
- Tamkun J. W., Hynes R. O. Plasma fibronectin is synthesized and secreted by hepatocytes. J Biol Chem. 1983 Apr 10;258(7):4641–4647. [PubMed] [Google Scholar]
- Tamkun J. W., Schwarzbauer J. E., Hynes R. O. A single rat fibronectin gene generates three different mRNAs by alternative splicing of a complex exon. Proc Natl Acad Sci U S A. 1984 Aug;81(16):5140–5144. doi: 10.1073/pnas.81.16.5140. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vibe-Pedersen K., Kornblihtt A. R., Baralle F. E. Expression of a human alpha-globin/fibronectin gene hybrid generates two mRNAs by alternative splicing. EMBO J. 1984 Nov;3(11):2511–2516. doi: 10.1002/j.1460-2075.1984.tb02165.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vibe-Pedersen K., Magnusson S., Baralle F. E. Donor and acceptor splice signals within an exon of the human fibronectin gene: a new type of differential splicing. FEBS Lett. 1986 Oct 27;207(2):287–291. doi: 10.1016/0014-5793(86)81506-x. [DOI] [PubMed] [Google Scholar]