Ubiquitin genes

Figure 7 Multiple roles of the deubiquitinating enzymes. Deubiquitinating enzymes (DUBs) of the UCH type (dark scissors) process ubiquitin precursors. UCH-L1 generates monoubiquitins from tandemly linked ubiquitin gene product. UCH-L3 acts on ubiquitin synthesized as a protein fused to small ribosomal subunits. DUBs of the UBP type (shaded scissors) process ubiquitins linked in isopeptide linkage in polyubiquitin chains. DUBs also reverse the ubiquitination on erroneously targeted substrates (editing). Another important function of DUBs is disassembly of polyubiquitin chains as the ubiquitinated substrate is degraded. Ubiquitin attached to substrates after activation are indicated as lollipop-like structures with filled circles. Free ubiquitin or ubiquitin unit in precursor is shown with open circles.

The preparation of mRNA of yeast ubiquitin is described under Subheadings 3.3.1.-3.3.2., including (a) the transcription of yeast ubiquitin gene with the plasmid pEU3b/ubiquitin by SP6 bacteriophage RNA polymerase, and (b) the quantitation of transcribed mRNA by a fluorometer. 

Ozkaynak, E., Finley, D., and Varshavsky, A. (1984) The yeast ubiquitin gene head-to-tail repeats encoding a polyubiquitin precursor protein. Nature 312, 663-666. 

Figure 2. Distribution of gene expression data from 50 prostatectomy samples measured with the U95Av2 Affymetrix microarray (a) histogram of the expression level of the HSYUBG1 Homo sapiens ubiquitin gene (b) histogram of the same gene expression level after the log-transformation was used.

Mizutani A, Nakagawa N, Hitomi K, and Tsukagoshi N (1997) Ascorbate-dependent expression of ubiquitin genes in guinea pigs. International Journal of Biochemistry and... 

Okubo, K., K. Yamano, Q. Qin, K. Aoyagi, M. Ototake, T. Nakanishi, H. Fukuda and J.M. Dijkstra. Ubiquitin genes in rainbow trout (Oncorhynchus mykiss). Fish Shellfish Immunol. 12 335-351, 2002. 

Ashley, C., Pastushok, L., McKenna, S., Ellison, M. J., and Xiao, W. (2002). Roles of mouse UBC13 in DNA postreplication repair and Lys63-linked ubiquitination. Gene 285, 183-191. 

Bond, U. Schlesinger, M.J. (1986). The chicken ubiquitin gene contains a heat shock promoter and expresses an unstable mRNA in heat shock cells, h/lol Cell Biol, 6, 4602-10. 

Mezquita, J. Mezquita, C. (1992). A cluster of tRNA genes is present in the 5 -flanking region of chicken ubiquitin gene Ubll. Nucl Acids Res.. 20. 5i77. 

F g.2. Structural organization of poly-ubiquitin precursor protein in Saccharomyces cerevisiae, deduced from the nucleotide sequence of the ubiquitin gene. Arrows indicate sites of proteolytic cleavage in the maturation process. The C-termi-nus (here Asn) varies according to the organism, e.g. Val in human, Tyr in chicken. 

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