TY  - JOUR
A1  - Schmidtke, Cornelius
A1  - Findeiß, Sven
A1  - Sharma, Cynthia M.
A1  - Kuhfuss, Juliane
A1  - Hoffmann, Steve
A1  - Vogel, Jörg
A1  - Stadler, Peter F.
A1  - Bonas, Ulla
T1  - Genome-wide transcriptome analysis of the plant pathogen Xanthomonas identifies sRNAs with putative virulence functions
JF  - Nucleic Acids Research
N2  - The Gram-negative plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria (Xcv) is an important model to elucidate the mechanisms involved in the interaction with the host. To gain insight into the transcriptome of the Xcv strain 85-10, we took a differential RNA sequencing (dRNA-seq) approach. Using a novel method to automatically generate comprehensive transcription start site (TSS) maps we report 1421 putative TSSs in the Xcv genome. Genes in Xcv exhibit a poorly conserved -10 promoter element and no consensus Shine-Dalgarno sequence. Moreover, 14% of all mRNAs are leaderless and 13% of them have unusually long 5'-UTRs. Northern blot analyses confirmed 16 intergenic small RNAs and seven cis-encoded antisense RNAs in Xcv. Expression of eight intergenic transcripts was controlled by HrpG and HrpX, key regulators of the Xcv type III secretion system. More detailed characterization identified sX12 as a small RNA that controls virulence of Xcv by affecting the interaction of the pathogen and its host plants. The transcriptional landscape of Xcv is unexpectedly complex, featuring abundant antisense transcripts, alternative TSSs and clade-specific small RNAs.
KW  - SUBSP carotovora
KW  - regulatory RNA
KW  - gene-cluster
KW  - campestris PV vesicatoria
KW  - escherichia coli
KW  - determines pathgenicity
KW  - hypersensitive response
KW  - ralstonia solanacearum
KW  - extracellular enzymes
KW  - secretion systems
KW  - transcription initiation site
KW  - RNA sequence analyses
KW  - messanger RNA
KW  - plants
KW  - libraries
KW  - genome
KW  - genes
KW  - gene expression profiling
KW  - genetic transcription
KW  - northern blotting
KW  - untranslated regions
KW  - xanthomonas
KW  - xanthomonas campestris
KW  - bacteria
KW  - virulence
KW  - pathogenetic organism
KW  - RNA
KW  - small RNA
KW  - pathogenicity
KW  - type III secretion system pathways
KW  - maps
KW  - consesus
KW  - host (organism)
KW  - type III protein secretion system complex
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131781
VL  - 40
IS  - 5
SP  - 2020
EP  - 2031
ER  - 
TY  - JOUR
A1  - Wilms, Ina
A1  - Overlöper, Aaron
A1  - Nowrousian, Minou
A1  - Sharma, Cynthia M.
A1  - Narberhaus, Franz
T1  - Deep sequencing uncovers numerous small RNAs on all four replicons of the plant pathogen Agrobacterium tumefaciens
JF  - RNA Biology
N2  - Agrobacterium species are capable of interkingdom gene transfer between bacteria and plants. The genome of Agrobacterium tumefaciens consists of a circular and a linear chromosome, the At-plasmid and the Ti-plasmid, which harbors bacterial virulence genes required for tumor formation in plants. Little is known about promoter sequences and the small RNA (sRNA) repertoire of this and other α-proteobacteria. We used a differential RNA sequencing (dRNA-seq) approach to map transcriptional start sites of 388 annotated genes and operons. In addition, a total number of 228 sRNAs was revealed from all four Agrobacterium replicons. Twenty-two of these were confirmed by independent RNA gel blot analysis and several sRNAs were differentially expressed in response to growth media, growth phase, temperature or pH. One sRNA from the Ti-plasmid was massively induced under virulence conditions. The presence of 76 cis-antisense sRNAs, two of them on the reverse strand of virulence genes, suggests considerable antisense transcription in Agrobacterium. The information gained from this study provides a valuable reservoir for an in-depth understanding of sRNA-mediated regulation of the complex physiology and infection process of Agrobacterium.
KW  - regulatory RNA
KW  - plant-microbe interaction
KW  - deep sequencing
KW  - RNA-seq
KW  - small RNA
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127101
VL  - 9
IS  - 446-457
ER  -