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. 1985 Sep 25;13(18):6577–6590. doi: 10.1093/nar/13.18.6577

Single stranded DNA binding proteins derive from hnRNP proteins by proteolysis in mammalian cells.

M Pandolfo, O Valentini, G Biamonti, C Morandi, S Riva
PMCID: PMC321978  PMID: 3903656

Abstract

As we have previously demonstrated, mammalian single stranded DNA binding proteins (ssDBP) and heterogeneous nuclear RNA binding proteins (hnRNP proteins) are antigenically and structurally related. In this paper we show that ssDBP are specific proteolytic products of hnRNP core proteins. Proteolysis can be observed in crude extract, both total and nuclear and is not inhibited by the most commonly used protease inhibitors. Such phenomenon can be observed in HeLa cells, human fibroblasts and calf thymus extracts. A trypsin-like protease that cleaves purified hnRNP proteins to give ssDBP of Mr = 24-28 Kd can be purified from HeLa cells. A precursor-product relationship can be established between hnRNP core proteins type A and an ssDBP of 24 Kd (UP1).

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Selected References

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

  1. Beyer A. L., Christensen M. E., Walker B. W., LeStourgeon W. M. Identification and characterization of the packaging proteins of core 40S hnRNP particles. Cell. 1977 May;11(1):127–138. doi: 10.1016/0092-8674(77)90323-3. [DOI] [PubMed] [Google Scholar]
  2. Douglass J., Civelli O., Herbert E. Polyprotein gene expression: generation of diversity of neuroendocrine peptides. Annu Rev Biochem. 1984;53:665–715. doi: 10.1146/annurev.bi.53.070184.003313. [DOI] [PubMed] [Google Scholar]
  3. Fakan S., Leser G., Martin T. E. Ultrastructural distribution of nuclear ribonucleoproteins as visualized by immunocytochemistry on thin sections. J Cell Biol. 1984 Jan;98(1):358–363. doi: 10.1083/jcb.98.1.358. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Herrick G., Alberts B. Purification and physical characterization of nucleic acid helix-unwinding proteins from calf thymus. J Biol Chem. 1976 Apr 10;251(7):2124–2132. [PubMed] [Google Scholar]
  5. Jones R. E., Okamura C. S., Martin T. E. Immunofluorescent localization of the proteins of nuclear ribonucleoprotein complexes. J Cell Biol. 1980 Jul;86(1):235–243. doi: 10.1083/jcb.86.1.235. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  7. Leser G. P., Escara-Wilke J., Martin T. E. Monoclonal antibodies to heterogeneous nuclear RNA-protein complexes. The core proteins comprise a conserved group of related polypeptides. J Biol Chem. 1984 Feb 10;259(3):1827–1833. [PubMed] [Google Scholar]
  8. Pederson T. Nuclear RNA-protein interactions and messenger RNA processing. J Cell Biol. 1983 Nov;97(5 Pt 1):1321–1326. doi: 10.1083/jcb.97.5.1321. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Peters K. E., Commings D. E. Two-dimensinal gel electrophoresis of rat liver nuclear washes, nuclear matrix, and hnRNA proteins. J Cell Biol. 1980 Jul;86(1):135–155. doi: 10.1083/jcb.86.1.135. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Planck S. R., Wilson S. H. Studies on the structure of mouse helix-destabilizing protein-1. DNA binding and controlled proteolysis with trypsin. J Biol Chem. 1980 Dec 10;255(23):11547–11556. [PubMed] [Google Scholar]
  11. Valentini O., Biamonti G., Mastromei G., Riva S. Structural and functional heterogeneity of single-stranded DNA-binding proteins from calf thymus. Biochim Biophys Acta. 1984 Jun 16;782(2):147–155. doi: 10.1016/0167-4781(84)90018-6. [DOI] [PubMed] [Google Scholar]
  12. Valentini O., Biamonti G., Pandolfo M., Morandi C., Riva S. Mammalian single-stranded DNA binding proteins and heterogeneous nuclear RNA proteins have common antigenic determinants. Nucleic Acids Res. 1985 Jan 25;13(2):337–346. doi: 10.1093/nar/13.2.337. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Wilk H. E., Werr H., Friedrich D., Kiltz H. H., Schäfer K. P. The core proteins of 35S hnRNP complexes. Characterization of nine different species. Eur J Biochem. 1985 Jan 2;146(1):71–81. doi: 10.1111/j.1432-1033.1985.tb08621.x. [DOI] [PubMed] [Google Scholar]
  14. Zieve G., Penman S. Subnuclear particles containing a small nuclear RNA and heterogeneous nuclear RNA. J Mol Biol. 1981 Jan 25;145(3):501–523. doi: 10.1016/0022-2836(81)90542-8. [DOI] [PubMed] [Google Scholar]

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