Disease relevance of rpsT

• A spontaneous mutant of Escherichia coli K-12 was isolated that shows an increased misreading ability of all three nonsense codons together with an inability to grow at 42 degrees C. It is demonstrated that the mutation is a deletion of the gene rpsT, coding for ribosomal protein S20 [1].
• With help of these phages it has been shown that the gene sups20 (Böck et al., 1974) corresponds to rpsT, the structural gene for ribosomal protein S20 [2].

High impact information on rpsT

• A wild-type gene located within 2 kilobase pairs counterclockwise of rpsT increases the Na+/H+ antiport activity when present in multiple copies [3].
• The x gene is transcribed in the same direction as that of the ileS-lsp operon and opposite to that of the upstream adjacent rpsT gene [4].
• To identify the promoter for the ileS-lsp operon, we have determined the nucleotide sequence of an 1.8-kilobase DNA fragment between the rpsT and IleS genes [4].
• Examination of the nucleotide sequence of the gene for ribosomal protein S20 (rpsT) of Escherichia coli suggested the presence of two promoters ("sites 1 and 2") separated by 90 base pairs (Mackie, G. A. (1981) J. Biol. Chem. 256, 8177-8182) [5].
• This stabilization is dependent on efficient translational initiation and ribosome transit through at least two-thirds of the coding sequence past a major RNase E cleavage site in the rpsT mRNA [6].

Biological context of rpsT

• Mutations in the leader sequence and initiation codon of the gene for ribosomal protein S20 (rpsT) affect both translational efficiency and autoregulation [7].
• Over a range of total copies of rpsT of 1 to 58 per haploid genome equivalent, the rate of incorporation of uridine during a 30-s pulse into RNA annealing to either of two specific probes for S20 mRNA increased essentially in proportion to copy number [8].
• We have exploited the properties of three different plasmids which carry the gene for Escherichia coli ribosomal protein S20 (rpsT) to test the effects of gene dosage on the expression of rpsT [8].

Anatomical context of rpsT

• It is suggested that two modified bases, m5C and m6(2)A, are directly or indirectly essential for association of subunits to functional ribosomes in the rpsT mutant strain [1].

Other interactions of rpsT

• Surprisingly, analysis of the DNA sequence flanking dnaA revealed none of these genes, except for an rpsT homolog, also found upstream of dnaA in C. crescentus [9].

References