English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The GntR family transcription regulator HpaR1 identified from  Xanthomonas campestris  pv.  campestris  has been previously shown to positively regulate the genes responsible for hypersensitive reaction and pathogenicity and to autorepress its own expression. Here, we demonstrated that HpaR1 is a global regulator that positively regulates diverse biological processes, including xanthan polysaccharide production, extracellular enzyme activity, cell motility and tolerance to various stresses. To investigate the regulatory mechanisms of HpaR1, we began with xanthan polysaccharide production, which is governed by a cluster of  gum  genes. These are directed by the  gumB  promoter. Disruption of HpaR1 significantly reduced  gumB  transcription and an electrophoretic mobility shift assay demonstrated that HpaR1 interacts directly with  gumB  promoter. DNase I footprint analysis revealed that HpaR1 and RNA polymerase were bound to the sequences extending from −21 to +10 and −41 to +29 relative to the transcription initiation site of  gumB , respectively. Furthermore,  in vitro  transcription assays showed that HpaR1 facilitated the binding of RNA polymerase to  gumB  promoter, leading to an enhancement of its transcription. These results suggest that HpaR1 regulates  gumB  transcription via a mechanism similar but different to what was found, until now, to only be used by some MerR family transcription activators.

Characterization of the GntR family regulator HpaR1 of the crucifer black rot pathogen Xanthomonas campestris pathovar campestris