Abstract
The degradation of many proteins involves the sequential ligation of ubiquitin molecules to the substrate to form a multiubiquitin chain linked through Lys-48 of ubiquitin. To test for the existence of alternate forms of multiubiquitin chains, we examined the effects of individually substituting each of six other Lys residues in ubiquitin with Arg. Substitution of Lys-63 resulted in the disappearance of a family of abundant multiubiquitin-protein conjugates. The UbK63R mutants were not generally impaired in ubiquitination, because they grew at a wild-type rate, were fully proficient in the turnover of a variety of short-lived proteins, and exhibited normal levels of many ubiquitin-protein conjugates. The UbK63R mutation also conferred sensitivity to the DNA-damaging agents methyl methanesulfonate and UV as well as a deficiency in DNA damage-induced mutagenesis. Induced mutagenesis is mediated by a repair pathway that requires Rad6 (Ubc2), a ubiquitin-conjugating enzyme. Thus, the UbK63R mutant appears to be deficient in the Rad6 pathway of DNA repair. However, the UbK63R mutation behaves as a partial suppressor of a rad6 deletion mutation, indicating that an effect of UbK63R on repair can be manifest in the absence of the Rad6 gene product. The UbK63R mutation may therefore define a new role of ubiquitin in DNA repair. The results of this study suggest that Lys-63 is used as a linkage site in the formation of novel multiubiquitin chain structures that play an important role in DNA repair.
Full Text
The Full Text of this article is available as a PDF (486.3 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aboussekhra A., Chanet R., Zgaga Z., Cassier-Chauvat C., Heude M., Fabre F. RADH, a gene of Saccharomyces cerevisiae encoding a putative DNA helicase involved in DNA repair. Characteristics of radH mutants and sequence of the gene. Nucleic Acids Res. 1989 Sep 25;17(18):7211–7219. doi: 10.1093/nar/17.18.7211. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Alani E., Cao L., Kleckner N. A method for gene disruption that allows repeated use of URA3 selection in the construction of multiply disrupted yeast strains. Genetics. 1987 Aug;116(4):541–545. doi: 10.1534/genetics.112.541.test. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bachmair A., Finley D., Varshavsky A. In vivo half-life of a protein is a function of its amino-terminal residue. Science. 1986 Oct 10;234(4773):179–186. doi: 10.1126/science.3018930. [DOI] [PubMed] [Google Scholar]
- Bailly V., Lamb J., Sung P., Prakash S., Prakash L. Specific complex formation between yeast RAD6 and RAD18 proteins: a potential mechanism for targeting RAD6 ubiquitin-conjugating activity to DNA damage sites. Genes Dev. 1994 Apr 1;8(7):811–820. doi: 10.1101/gad.8.7.811. [DOI] [PubMed] [Google Scholar]
- Bartel B., Wünning I., Varshavsky A. The recognition component of the N-end rule pathway. EMBO J. 1990 Oct;9(10):3179–3189. doi: 10.1002/j.1460-2075.1990.tb07516.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Boeke J. D., LaCroute F., Fink G. R. A positive selection for mutants lacking orotidine-5'-phosphate decarboxylase activity in yeast: 5-fluoro-orotic acid resistance. Mol Gen Genet. 1984;197(2):345–346. doi: 10.1007/BF00330984. [DOI] [PubMed] [Google Scholar]
- Chau V., Tobias J. W., Bachmair A., Marriott D., Ecker D. J., Gonda D. K., Varshavsky A. A multiubiquitin chain is confined to specific lysine in a targeted short-lived protein. Science. 1989 Mar 24;243(4898):1576–1583. doi: 10.1126/science.2538923. [DOI] [PubMed] [Google Scholar]
- Chen P., Johnson P., Sommer T., Jentsch S., Hochstrasser M. Multiple ubiquitin-conjugating enzymes participate in the in vivo degradation of the yeast MAT alpha 2 repressor. Cell. 1993 Jul 30;74(2):357–369. doi: 10.1016/0092-8674(93)90426-q. [DOI] [PubMed] [Google Scholar]
- Chen Z., Pickart C. M. A 25-kilodalton ubiquitin carrier protein (E2) catalyzes multi-ubiquitin chain synthesis via lysine 48 of ubiquitin. J Biol Chem. 1990 Dec 15;265(35):21835–21842. [PubMed] [Google Scholar]
- Ciechanover A., Finley D., Varshavsky A. Ubiquitin dependence of selective protein degradation demonstrated in the mammalian cell cycle mutant ts85. Cell. 1984 May;37(1):57–66. doi: 10.1016/0092-8674(84)90300-3. [DOI] [PubMed] [Google Scholar]
- Cook W. J., Jeffrey L. C., Carson M., Chen Z., Pickart C. M. Structure of a diubiquitin conjugate and a model for interaction with ubiquitin conjugating enzyme (E2). J Biol Chem. 1992 Aug 15;267(23):16467–16471. doi: 10.2210/pdb1aar/pdb. [DOI] [PubMed] [Google Scholar]
- Cook W. J., Jeffrey L. C., Kasperek E., Pickart C. M. Structure of tetraubiquitin shows how multiubiquitin chains can be formed. J Mol Biol. 1994 Feb 18;236(2):601–609. doi: 10.1006/jmbi.1994.1169. [DOI] [PubMed] [Google Scholar]
- Deveraux Q., Ustrell V., Pickart C., Rechsteiner M. A 26 S protease subunit that binds ubiquitin conjugates. J Biol Chem. 1994 Mar 11;269(10):7059–7061. [PubMed] [Google Scholar]
- Dohmen R. J., Madura K., Bartel B., Varshavsky A. The N-end rule is mediated by the UBC2(RAD6) ubiquitin-conjugating enzyme. Proc Natl Acad Sci U S A. 1991 Aug 15;88(16):7351–7355. doi: 10.1073/pnas.88.16.7351. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ecker D. J., Khan M. I., Marsh J., Butt T. R., Crooke S. T. Chemical synthesis and expression of a cassette adapted ubiquitin gene. J Biol Chem. 1987 Mar 15;262(8):3524–3527. [PubMed] [Google Scholar]
- Enoch T., Carr A. M., Nurse P. Fission yeast genes involved in coupling mitosis to completion of DNA replication. Genes Dev. 1992 Nov;6(11):2035–2046. doi: 10.1101/gad.6.11.2035. [DOI] [PubMed] [Google Scholar]
- Finley D., Bartel B., Varshavsky A. The tails of ubiquitin precursors are ribosomal proteins whose fusion to ubiquitin facilitates ribosome biogenesis. Nature. 1989 Mar 30;338(6214):394–401. doi: 10.1038/338394a0. [DOI] [PubMed] [Google Scholar]
- Finley D., Chau V. Ubiquitination. Annu Rev Cell Biol. 1991;7:25–69. doi: 10.1146/annurev.cb.07.110191.000325. [DOI] [PubMed] [Google Scholar]
- Finley D., Ozkaynak E., Varshavsky A. The yeast polyubiquitin gene is essential for resistance to high temperatures, starvation, and other stresses. Cell. 1987 Mar 27;48(6):1035–1046. doi: 10.1016/0092-8674(87)90711-2. [DOI] [PubMed] [Google Scholar]
- Finley D., Sadis S., Monia B. P., Boucher P., Ecker D. J., Crooke S. T., Chau V. Inhibition of proteolysis and cell cycle progression in a multiubiquitination-deficient yeast mutant. Mol Cell Biol. 1994 Aug;14(8):5501–5509. doi: 10.1128/mcb.14.8.5501. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gietz R. D., Prakash S. Cloning and nucleotide sequence analysis of the Saccharomyces cerevisiae RAD4 gene required for excision repair of UV-damaged DNA. Gene. 1988 Dec 30;74(2):535–541. doi: 10.1016/0378-1119(88)90186-2. [DOI] [PubMed] [Google Scholar]
- Goebl M. G., Yochem J., Jentsch S., McGrath J. P., Varshavsky A., Byers B. The yeast cell cycle gene CDC34 encodes a ubiquitin-conjugating enzyme. Science. 1988 Sep 9;241(4871):1331–1335. doi: 10.1126/science.2842867. [DOI] [PubMed] [Google Scholar]
- Haas A. L., Bright P. M. The immunochemical detection and quantitation of intracellular ubiquitin-protein conjugates. J Biol Chem. 1985 Oct 15;260(23):12464–12473. [PubMed] [Google Scholar]
- Haas A. L., Reback P. B., Chau V. Ubiquitin conjugation by the yeast RAD6 and CDC34 gene products. Comparison to their putative rabbit homologs, E2(20K) AND E2(32K). J Biol Chem. 1991 Mar 15;266(8):5104–5112. [PubMed] [Google Scholar]
- Hershko A., Ciechanover A. The ubiquitin system for protein degradation. Annu Rev Biochem. 1992;61:761–807. doi: 10.1146/annurev.bi.61.070192.003553. [DOI] [PubMed] [Google Scholar]
- Hochstrasser M., Ellison M. J., Chau V., Varshavsky A. The short-lived MAT alpha 2 transcriptional regulator is ubiquitinated in vivo. Proc Natl Acad Sci U S A. 1991 Jun 1;88(11):4606–4610. doi: 10.1073/pnas.88.11.4606. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jabusch J. R., Deutsch H. F. Localization of lysines acetylated in ubiquitin reacted with p-nitrophenyl acetate. Arch Biochem Biophys. 1985 Apr;238(1):170–177. doi: 10.1016/0003-9861(85)90153-5. [DOI] [PubMed] [Google Scholar]
- James A. P., Kilbey B. J. The timing of UV mutagenesis in yeast: a pedigree analysis of induced recessive mutation. Genetics. 1977 Oct;87(2):237–248. doi: 10.1093/genetics/87.2.237. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jentsch S., McGrath J. P., Varshavsky A. The yeast DNA repair gene RAD6 encodes a ubiquitin-conjugating enzyme. Nature. 1987 Sep 10;329(6135):131–134. doi: 10.1038/329131a0. [DOI] [PubMed] [Google Scholar]
- Jentsch S. The ubiquitin-conjugation system. Annu Rev Genet. 1992;26:179–207. doi: 10.1146/annurev.ge.26.120192.001143. [DOI] [PubMed] [Google Scholar]
- Johnson E. S., Bartel B., Seufert W., Varshavsky A. Ubiquitin as a degradation signal. EMBO J. 1992 Feb;11(2):497–505. doi: 10.1002/j.1460-2075.1992.tb05080.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kilbey B. J., James A. P. The mutagenic potential of unexcised pyrimidine dimers in Saccharomyces cerevisiae, rad1-1: evidence from photoreactivation and pedigree analysis. Mutat Res. 1979 Apr;60(2):163–171. doi: 10.1016/0027-5107(79)90180-5. [DOI] [PubMed] [Google Scholar]
- Koken M. H., Reynolds P., Jaspers-Dekker I., Prakash L., Prakash S., Bootsma D., Hoeijmakers J. H. Structural and functional conservation of two human homologs of the yeast DNA repair gene RAD6. Proc Natl Acad Sci U S A. 1991 Oct 15;88(20):8865–8869. doi: 10.1073/pnas.88.20.8865. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lawrence C. The RAD6 DNA repair pathway in Saccharomyces cerevisiae: what does it do, and how does it do it? Bioessays. 1994 Apr;16(4):253–258. doi: 10.1002/bies.950160408. [DOI] [PubMed] [Google Scholar]
- Madura K., Varshavsky A. Degradation of G alpha by the N-end rule pathway. Science. 1994 Sep 2;265(5177):1454–1458. doi: 10.1126/science.8073290. [DOI] [PubMed] [Google Scholar]
- Mann R. K., Grunstein M. Histone H3 N-terminal mutations allow hyperactivation of the yeast GAL1 gene in vivo. EMBO J. 1992 Sep;11(9):3297–3306. doi: 10.1002/j.1460-2075.1992.tb05408.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morrison A., Christensen R. B., Alley J., Beck A. K., Bernstine E. G., Lemontt J. F., Lawrence C. W. REV3, a Saccharomyces cerevisiae gene whose function is required for induced mutagenesis, is predicted to encode a nonessential DNA polymerase. J Bacteriol. 1989 Oct;171(10):5659–5667. doi: 10.1128/jb.171.10.5659-5667.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Farrell P. H. High resolution two-dimensional electrophoresis of proteins. J Biol Chem. 1975 May 25;250(10):4007–4021. [PMC free article] [PubMed] [Google Scholar]
- Park E. C., Finley D., Szostak J. W. A strategy for the generation of conditional mutations by protein destabilization. Proc Natl Acad Sci U S A. 1992 Feb 15;89(4):1249–1252. doi: 10.1073/pnas.89.4.1249. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Prakash S., Sung P., Prakash L. DNA repair genes and proteins of Saccharomyces cerevisiae. Annu Rev Genet. 1993;27:33–70. doi: 10.1146/annurev.ge.27.120193.000341. [DOI] [PubMed] [Google Scholar]
- Rechsteiner M., Hoffman L., Dubiel W. The multicatalytic and 26 S proteases. J Biol Chem. 1993 Mar 25;268(9):6065–6068. [PubMed] [Google Scholar]
- Rong L., Klein H. L. Purification and characterization of the SRS2 DNA helicase of the yeast Saccharomyces cerevisiae. J Biol Chem. 1993 Jan 15;268(2):1252–1259. [PubMed] [Google Scholar]
- Scheffner M., Huibregtse J. M., Vierstra R. D., Howley P. M. The HPV-16 E6 and E6-AP complex functions as a ubiquitin-protein ligase in the ubiquitination of p53. Cell. 1993 Nov 5;75(3):495–505. doi: 10.1016/0092-8674(93)90384-3. [DOI] [PubMed] [Google Scholar]
- Schiestl R. H., Prakash S., Prakash L. The SRS2 suppressor of rad6 mutations of Saccharomyces cerevisiae acts by channeling DNA lesions into the RAD52 DNA repair pathway. Genetics. 1990 Apr;124(4):817–831. doi: 10.1093/genetics/124.4.817. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Seufert W., Jentsch S. Ubiquitin-conjugating enzymes UBC4 and UBC5 mediate selective degradation of short-lived and abnormal proteins. EMBO J. 1990 Feb;9(2):543–550. doi: 10.1002/j.1460-2075.1990.tb08141.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Seufert W., McGrath J. P., Jentsch S. UBC1 encodes a novel member of an essential subfamily of yeast ubiquitin-conjugating enzymes involved in protein degradation. EMBO J. 1990 Dec;9(13):4535–4541. doi: 10.1002/j.1460-2075.1990.tb07905.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sung P., Berleth E., Pickart C., Prakash S., Prakash L. Yeast RAD6 encoded ubiquitin conjugating enzyme mediates protein degradation dependent on the N-end-recognizing E3 enzyme. EMBO J. 1991 Aug;10(8):2187–2193. doi: 10.1002/j.1460-2075.1991.tb07754.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Varshavsky A. The N-end rule. Cell. 1992 May 29;69(5):725–735. doi: 10.1016/0092-8674(92)90285-k. [DOI] [PubMed] [Google Scholar]
- Vijay-Kumar S., Bugg C. E., Cook W. J. Structure of ubiquitin refined at 1.8 A resolution. J Mol Biol. 1987 Apr 5;194(3):531–544. doi: 10.1016/0022-2836(87)90679-6. [DOI] [PubMed] [Google Scholar]
- Wiebel F. F., Kunau W. H. The Pas2 protein essential for peroxisome biogenesis is related to ubiquitin-conjugating enzymes. Nature. 1992 Sep 3;359(6390):73–76. doi: 10.1038/359073a0. [DOI] [PubMed] [Google Scholar]
- Woffendin C., Chen Z. Y., Staskus K., Retzel E. F., Plagemann P. G. Mammalian mRNAs encoding protein closely related to ubiquitin-conjugating enzyme encoded by yeast DNA repair gene RAD6. Biochim Biophys Acta. 1991 Aug 27;1090(1):81–85. doi: 10.1016/0167-4781(91)90039-o. [DOI] [PubMed] [Google Scholar]
- van Nocker S., Vierstra R. D. Multiubiquitin chains linked through lysine 48 are abundant in vivo and are competent intermediates in the ubiquitin proteolytic pathway. J Biol Chem. 1993 Nov 25;268(33):24766–24773. [PubMed] [Google Scholar]