Disease relevance of hrpL

• Genome-wide gene expression analysis of Pseudomonas syringae pv. tomato DC3000 reveals overlapping and distinct pathways regulated by hrpL and hrpRS [1].

High impact information on hrpL

• Most were also dependent on the hrpL gene, but at least one was dependent on the hrpS gene, but not on the hrpL gene [2].
• We also showed that a mutation in hrpL, which encodes an alternate RNA polymerase sigma factor (sigmaL) required for the expression of genes encoding components of the type III secretion system, abrogated production of COR in P. syringae pv. tomato DC3000 [3].
• The presence of a potential hrp box, the recognition site for sigmaL, upstream of corR suggested that corR might be regulated by hrpL [3].
• The transcription of hrpL is activated by HrpR and HrpS, two homologous DNA-binding proteins encoded by the hrpRS operon [1].
• Tn3-gus saturation mutagenesis of the avrE locus and adjacent DNA revealed at least four transcriptional units occurring immediately adjacent to the hrpRS locus that were all regulated in a manner similar to hrp genes (induced only in minimal induction media or in planta and required the hrpL and hrpRS loci for expression) [4].

Other interactions of hrpL

• The corR mutant of P. syringae pv. tomato DC3000 showed both a reduction and delay in the expression of hrpL and was impaired in its ability to elicit a hypersensitive response on Nicotiana benthamiana [3].

Analytical, diagnostic and therapeutic context of hrpL

• Microarray analysis was conducted to evaluate the DC3000 genes regulated by hrpL and hrpRS in MM [1].

References