Disease relevance of traR

• PCR mutagenesis of a 0.9-kbp fragment, containing a repressor gene, traR, and its target promoter, Ptra, from Streptomyces nigrifaciens plasmid pSN22, produced Streptomyces lividans clones with temperature-inducible Ptra expression [1].
• An inducible Streptomyces expression cassette utilising the Ptra promoter and a temperature-sensitive allele of the TraR repressor from S. nigrifaciens plasmid pSN22 was tested in Mycobacterium smegmatis [2].

High impact information on traR

• In vitro promoter-probing experiments identified a 550-bp BglII-SmaI DNA fragment with promoter activity in both orientations; Northern (RNA blot) hybridization identified corresponding divergent transcripts of 1 and 5.2 kb for traR and the traA-traB-spdB operon, respectively [3].

Biological context of traR

• Plasmids with a functional traA gene but without traR had a low transformation efficiency and inhibited the growth of host cells [3].
• The traR gene product repressed its own transcription and also the transcription of the traA-traB-spdB operon [3].

References