Nonsense suppressor
A nonsense suppressor is a factor which can inhibit the effect of the
Nonsense suppressors are a useful genetic tool, but can also result in problematic side effects, since all identical stop codons in the genome will also be suppressed to the same degree. Genes with different or multiple stop codons will be unaffected.
SUP35, a nonsense suppressor identified by Wickner in 1994, is a prion protein.
In synthetic biology, artificial suppressor elongator tRNAs are used to incorporate
In recent research, a novel gene therapy approach is provided by Jiaming Wang and Yue Zhang.[8] They use an adeno-associated virus (AAV) vector to deliver a new suppressor tRNA (sup-tRNAtyr) into a mouse model carrying a nonsense mutation(Idua-W401X,TCG→TAG). This model recapitulates a human LSD, mucopolysaccharidosis disease type I (or Hurler Syndrome), caused by absence of the enzyme α-l-iduronidase (IDUA) leading to accumulation of glycosaminoglycans (GAG) and resulting pathogenesis.[9] This method rescues the pathogenic defects and is essentially stable for 6 months.
Bacteriophage T4
Escherichia coli strains carrying nonsense suppressor genes had a central role in the early work on bacteriophage genetics.[10] In particular, E. coli strains carrying amber suppressors (suppressors of the UAG nonsense codon) enabled the isolation and propagation of bacteriophage T4 mutants defective in phage assembly, morphogenesis, DNA replication, DNA repair and genetic recombination and thus facilitated the early study of these processes at a fundamental level.[11][12]
Archaea
Nonsense suppression by altered tRNA was demonstrated in the archaeon Haloferax volcana for the chain terminating stop codons UAG (amber), UAA (ochre) and UGA (opal).[13]
References