Disease relevance of dnaJ

• The products of the Escherichia coli dnaK, dnaJ, and grpE heat shock genes have been previously shown to be essential for bacteriophage lambda DNA replication at all temperatures and for bacterial survival under certain conditions [1].
• The Escherichia coli dnaJ gene product is required for bacteriophage lambda DNA replication at all temperatures [2].
• We have cloned the Francisella tularensis (Ft) grpE-dnaK-dnaJ heat-shock genes which are organized in that order [3].
• The nucleotide sequence of the dnaK operon cloned from Porphyromonas gingivalis revealed that the operon does not contain homologues of either dnaJ or grpE [4].
• The mutational lesions characteristic of a dnaJ null mutant--namely, temperature sensitivity for growth and defects in lambda phage and mini-F DNA replication--were all restored upon introduction of the cbpA gene on a multicopy plasmid [5].

High impact information on dnaJ

• These antigens have the amino acid sequence QKRAA, which is also present on the Escherichia coli heat-shock protein dnaJ [6].
• The activated T cells may cross-react with autologous dnaJ heat-shock proteins that are expressed at synovial sites of inflammation [6].
• Positive selection in autoimmunity: abnormal immune responses to a bacterial dnaJ antigenic determinant in patients with early rheumatoid arthritis [6].
• Strains carrying defective dnaK, dnaJ, or grpE alleles have enhanced synthesis of heat shock proteins at low temperature and fail to shut off the heat shock response after shift to high temperature [7].
• The susceptibility sequence to rheumatoid arthritis is a cross-reactive B cell epitope shared by the Escherichia coli heat shock protein dnaJ and the histocompatibility leukocyte antigen DRB10401 molecule [8].

Chemical compound and disease context of dnaJ

• The function of atJ1 was tested by complementation of a dnaJ deletion mutant of E. coli, allowing growth in minimal medium at 44 degrees C. The AtJ1 protein was expressed in E. coli as a fusion with the maltose binding protein [9].
• Effect of mutations in dnaK and dnaJ genes on cysteine operon expression in Escherichia coli [10].

Biological context of dnaJ

• Here we present the primary DNA sequence of the dnaJ gene [2].
• The cbpA chaperone gene function compensates for dnaJ in lambda plasmid replication during amino acid starvation of Escherichia coli [11].
• Presence of a weak promoter which reads only the dnaJ cistron was also suggested [12].
• In M9 succinate minimal medium the dnaJ mutant grew more slowly than the wild-type strain, indicating that this operon is functional [13].
• Gene fusions carrying the 5' half (433 nt) or more of the rpoH coding sequence exhibited normal shutoff of synthesis, and the fusion proteins produced were very unstable, like authentic sigma 32; both the shutoff of synthesis and the instability of protein were markedly affected by the dnaK and dnaJ mutations [14].

Anatomical context of dnaJ

• Cellular immune responses to dnaJ were higher in synovial fluid than in blood and higher in children with active disease than in children in remission [15].
• Neither normal children nor children with various chronic inflammatory diseases had lymphocyte proliferative responses to recombinant dnaJ [15].
• Complementation of a DnaK-deficient Escherichia coli strain with the dnaK/dnaJ operon of Brucella ovis reduces the rate of initial intracellular killing within the monocytic cell line U937 [16].
• The content of fatty acids extracted from the membranes of E. coli MC 1061 harboring the wild-type dnaKdnaJ alleles and its delta dnaJ and delta dnaKdnaJ derivatives was compared [17].

Associations of dnaJ with chemical compounds

• A Fraction II extract from dnaJ259 mutant bacteria was shown to be unable to replicate lambda dv DNA unless supplemented with an exogenous source of wild-type dnaJ protein [18].
• The dnaJ mutation that replaces aspartate-35 with asparagine (D35N) in the J-domain causes a defect in binding of DnaJ to DnaK [19].
• Minimal inhibitory concentrations and the titer of the wild-type strains, delta dnaJ and delta dnaKdnaJ mutants treated with ampicillin, chloramphenicol, and tetracycline were also determined [20].
• The ability of delta dnaKdnaJ mutant to survive carbon, nitrogen and phosphorus starvation is highly impaired while delta dnaJ mutant is characterized by the diminished survival of phosphorus starvation only. delta dnaKdnaJ mutant grows slowly utilizing maltose and glycerol and delta dnaJ mutant utilizes glycerol inefficiently [21].
• This effect is seen only at 42 degrees C. The influence of double dnaKdnaJ deletion but not single dnaJ deletion on novobiocin susceptibility was also demonstrated [22].

Regulatory relationships of dnaJ

• We present evidence that the rate of expression of the dnaJ protein is increased by heat shock under the control of the htpR (rpoH) gene product [2].

Other interactions of dnaJ

• The sizes of dnaJ and dnaK cistrons were estimated to be at most 1.2 +/- 0.5 and 2.1 +/- 0.4 kilobases, respectively [12].
• Plasmid pLC3-13 which had been isolated from Clarke and Carbon's collection as a plasmid carrying the lspA locus was shown to carry the dnaJ and rpsT loci [23].
• Overexpression of dnaK/dnaJ and groEL confers freeze tolerance to Escherichia coli [24].
• The djlA gene acts synergistically with dnaJ in promoting Escherichia coli growth [25].

Analytical, diagnostic and therapeutic context of dnaJ

• The dnaK and dnaJ genes were isolated as a cluster from a purple non-sulfur phototrophic bacterium, Rhodopseudomonas species No. 7 by a polymerase chain reaction (PCR) based method [26].
• Northern blot analyses with grpE-, dnaK-, and dnaJ-specific probes revealed that the three genes are co-transcribed as a 4.0-kb mRNA [27].

References