Suppressor-mutator

Suppressor Mutations Can Counteract Some of the Effects of Missense,... 

Kobayashi, K. Shoji, K. Shimizu, T Nakano, K. Sato, T. Kobayashi, Y Analysis of a suppressor mutation ssb (kinC) of sur0B20 (spoOA) mutation in Bacillus subtilis reveals that kinC encodes a histidine protein kinase. J. BacterioL, 177, 176-182 (1995)... 

Suppressor tRNAs constitute an experimentally induced variation in the genetic code to allow the reading of what are usually termination codons, much like the naturally occurring code variations described in Box 27-2. Nonsense suppression does not completely disrupt normal information transfer in a cell, because the cell usually has several copies of each tRNA gene some of these duplicate genes are weakly expressed and account for only a minor part of the cellular pool of a particular tRNA. Suppressor mutations usually involve a minor tRNA, leaving the major tRNA to read its codon normally. 

Suppressor mutation. A mutation that restores a function lost by an initial mutation and that is located at a site different from the initial mutation. 

Zhang, Y., Oldenburg, M., and Fillingame, R. H. (1994). Suppressor mutations in Fj subunit t recouple ATP-driven H+ translocation in uncoupled Q42E subunit c mutant of Escherichia coli FiFo ATP synthase./. Biol. Chem. 269, 10221-10224. 

In the methionine system, suppressor mutations are selected on methionine-less medium with strains of A. nidulans requiring methionine because of blocks in any of eight genes, usually methGl. No true reversions are... 

Mutant m-51 also contained three substitutions AlaBBOVal, Ala98l=>Thr in the mature enzyme and AlaSl Thr in the pro-region. The suppressor mutation was found to be Ala31 OThr. None of the cold active variants in this study showed any loss of stability relative to wild type. This work demonstrates that activity can be increased at low temperatures, and that it can be done at no cost to thermostability. 

One mechanism that may be important in determining protein plasticity is the occurrence of second site suppressor mutations that serve to compensate for deleterious amino acid substitutions that interfere with... 

The prlB and prlC genes were also identified as sites of suppressor mutations that restore export to mutant X-receptor proteins (Emr et al.,... 

Although the mechanisms eliciting the angiogenic switch are not entirely understood to date, it is believed that besides tumor-suppressor mutation and oncogene activation, hypoxia plays a pivotal role [77]. 

Functionally significant interactions between proteins can be deduced from the phenotypic effects of allele-specific suppressor mutations or synthetic lethal mutations. 

A number of experimental approaches can be used to analyze mutations. Describe how complementation analysis can be used to reveal whether two mutations are in the same or in different genes. What are suppressor mutations and synthetic lethal mutations ... 

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