Abstract
The substrates of ubiquitin-dependent proteolytic pathways include both damaged or otherwise abnormal proteins and undamaged proteins that are naturally short-lived. Few specific examples of the latter class have been identified, however. Previous work has shown that the cell type-specific MAT alpha 2 repressor of the yeast Saccharomyces cerevisiae is an extremely short-lived protein. We now demonstrate that alpha 2 is conjugated to ubiquitin in vivo. More than one lysine residue of alpha 2 can be joined to ubiquitin, and some of the ubiquitin moieties form a Lys48-linked multiubiquitin chain. Overexpression of degradation-impaired ubiquitin variants was used to show that at least a significant fraction of alpha 2 degradation is dependent on its ubiquitination.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- 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]
- 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]
- 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]
- Ciechanover A., Schwartz A. L. How are substrates recognized by the ubiquitin-mediated proteolytic system? Trends Biochem Sci. 1989 Dec;14(12):483–488. doi: 10.1016/0968-0004(89)90180-1. [DOI] [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]
- Evan G. I., Lewis G. K., Ramsay G., Bishop J. M. Isolation of monoclonal antibodies specific for human c-myc proto-oncogene product. Mol Cell Biol. 1985 Dec;5(12):3610–3616. doi: 10.1128/mcb.5.12.3610. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Field J., Nikawa J., Broek D., MacDonald B., Rodgers L., Wilson I. A., Lerner R. A., Wigler M. Purification of a RAS-responsive adenylyl cyclase complex from Saccharomyces cerevisiae by use of an epitope addition method. Mol Cell Biol. 1988 May;8(5):2159–2165. doi: 10.1128/mcb.8.5.2159. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gietz R. D., Sugino A. New yeast-Escherichia coli shuttle vectors constructed with in vitro mutagenized yeast genes lacking six-base pair restriction sites. Gene. 1988 Dec 30;74(2):527–534. doi: 10.1016/0378-1119(88)90185-0. [DOI] [PubMed] [Google Scholar]
- Glotzer M., Murray A. W., Kirschner M. W. Cyclin is degraded by the ubiquitin pathway. Nature. 1991 Jan 10;349(6305):132–138. doi: 10.1038/349132a0. [DOI] [PubMed] [Google Scholar]
- Herskowitz I. A regulatory hierarchy for cell specialization in yeast. Nature. 1989 Dec 14;342(6251):749–757. doi: 10.1038/342749a0. [DOI] [PubMed] [Google Scholar]
- Hochstrasser M., Varshavsky A. In vivo degradation of a transcriptional regulator: the yeast alpha 2 repressor. Cell. 1990 May 18;61(4):697–708. doi: 10.1016/0092-8674(90)90481-s. [DOI] [PubMed] [Google Scholar]
- Jabben M., Shanklin J., Vierstra R. D. Ubiquitin-phytochrome conjugates. Pool dynamics during in vivo phytochrome degradation. J Biol Chem. 1989 Mar 25;264(9):4998–5005. [PubMed] [Google Scholar]
- Jentsch S., Seufert W., Sommer T., Reins H. A. Ubiquitin-conjugating enzymes: novel regulators of eukaryotic cells. Trends Biochem Sci. 1990 May;15(5):195–198. doi: 10.1016/0968-0004(90)90161-4. [DOI] [PubMed] [Google Scholar]
- Kellerman K. A., Mattson D. M., Duncan I. Mutations affecting the stability of the fushi tarazu protein of Drosophila. Genes Dev. 1990 Nov;4(11):1936–1950. doi: 10.1101/gad.4.11.1936. [DOI] [PubMed] [Google Scholar]
- Kunkel T. A., Roberts J. D., Zakour R. A. Rapid and efficient site-specific mutagenesis without phenotypic selection. Methods Enzymol. 1987;154:367–382. doi: 10.1016/0076-6879(87)54085-x. [DOI] [PubMed] [Google Scholar]
- Lüscher B., Eisenman R. N. c-myc and c-myb protein degradation: effect of metabolic inhibitors and heat shock. Mol Cell Biol. 1988 Jun;8(6):2504–2512. doi: 10.1128/mcb.8.6.2504. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Murray A. W., Solomon M. J., Kirschner M. W. The role of cyclin synthesis and degradation in the control of maturation promoting factor activity. Nature. 1989 May 25;339(6222):280–286. doi: 10.1038/339280a0. [DOI] [PubMed] [Google Scholar]
- Nasmyth K., Adolf G., Lydall D., Seddon A. The identification of a second cell cycle control on the HO promoter in yeast: cell cycle regulation of SW15 nuclear entry. Cell. 1990 Aug 24;62(4):631–647. doi: 10.1016/0092-8674(90)90110-z. [DOI] [PubMed] [Google Scholar]
- Ozkaynak E., Finley D., Solomon M. J., Varshavsky A. The yeast ubiquitin genes: a family of natural gene fusions. EMBO J. 1987 May;6(5):1429–1439. doi: 10.1002/j.1460-2075.1987.tb02384.x. [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]
- Sikorski R. S., Hieter P. A system of shuttle vectors and yeast host strains designed for efficient manipulation of DNA in Saccharomyces cerevisiae. Genetics. 1989 May;122(1):19–27. doi: 10.1093/genetics/122.1.19. [DOI] [PMC free article] [PubMed] [Google Scholar]