title: Analysis of the function of mycobacterial DnaJ proteins by overexpression and microarray profiling.
abstract: Regulation of expression of the Hsp70/DnaK chaperone plays an important role during infection with Mycobacterium tuberculosis. We have examined the effect of manipulating the level of expression of DnaJ, one of the components of the chaperone apparatus. Overexpression of DnaJ1 resulted in elevated transcription of both the hsp70/dnaK and hsp60/groE chaperone genes, consistent with an increase in the cellular content of nascent and unfolded peptide substrates. There was also an increase in transcription of genes flanking the origin of chromosomal replication, suggesting an important role for DnaJ1 in controlling interaction of the Hsp70 chaperone with the DnaA protein. Overexpression of DnaJ2 had no detectable effect on transcription of other genes. Overexpression in combination with microarray profiling provides a complementary approach to gene deletion for exploring the function of essential genes in M. tuberculosis.
authors.affiliation: Centre for Molecular Microbiology and Infection, Flowers Building, South Kensington Campus, Imperial College London, SW7 2AZ, UK. g.stewart@imperial.ac.uk
authors.forename: Graham R
authors.initials: GR
authors.lastname: Stewart
authors.forename: Brian D
authors.initials: BD
authors.lastname: Robertson
authors.forename: Douglas B
authors.initials: DB
authors.lastname: Young
mesh_terms: D000595:Amino Acid Sequence; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005822:Genetic Vectors; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D016415:Sequence Alignment; D014158:Transcription, Genetic
chemical_list: D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins