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J Peden

Publications and source records attributed to J Peden.

3 recordsLinked to original sources

Cloning and sequencing of the Atlantic salmon (Salmo salar) cytochrome c oxidase subunit III gene (coxIII) and analysis of coxIII expression during parr-smolt transformation.

Smoltification is the process whereby salmon alter their metabolism in preparation for movement from freshwater to seawater. Differential screening of a cDNA library prepared from post-smolt salmon liver mRNA led to the selection of a smoltification-induced sequence. Analysis of this cDNA revealed that it partially encoded subunit III of the enzyme cytochrome c oxidase. The complete coxIII sequence was amplified from salmon genomic DNA using consensus oligonucleotides based on ATPase 6 and tRNA(GLY) sequences from Pacific salmonid species. Cytochrome c oxidase subunit III liver mRNA levels were found to be significantly increased in salmon smolts. Northern blot analysis revealed a coxIII transcript of approximately 750 bp in all salmon tissues tested except blood. The DNA sequence of coxIII employs the mammalian mitochondrial genetic code and is strongly conserved when compared with that of other species.

Amino Acid Sequence

Upstream stimulators for recoding.

Recent progress in elucidation of 5' stimulatory elements for translational recoding is reviewed. A 5' Shine-Dalgarno sequence increases both +1 and -1 frameshift efficiency in several genes; examples cited include the E. coli prfB gene encoding release factor 2 and the dnaX gene encoding the gamma and tau subunits of DNA polymerase III holoenzyme. The spacing between the Shine-Dalgarno sequence and the shift site is critical in both the +1 and -1 frameshift cassettes; however, the optimal spacing is quite different in the two cases. A frameshift in a mammalian chromosomal gene, ornithine decarboxylase antizyme, has recently been reported; 5' sequences have been shown to be vital for this frameshift event. Escherichia coli bacteriophage T4 gene 60 encodes a subunit of its type II DNA topoisomerase. The mature gene 60 mRNA contains an internal 50 nucleotide region that appears to be bypassed during translation. A 16 amino acid domain of the nascent peptide is necessary for this bypass to occur.

Animals