@article{fdi:010048496,
  title = {{R}ickettsia conorii transcriptional response within inoculation eschar},
  author = {{R}enesto, {P}. and {R}overy, {C}. and {S}chrenzel, {J}. and {L}eroy, {Q}. and {H}uyghe, {A}. and {L}i, {W}. {J}. and {L}epidi, {H}. and {F}rancois, {P}. and {R}aoult, {D}idier},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground: {R}ickettsia conorii, the causative agent of the {M}editerranean spotted fever, is transmitted to humans by the bite of infected ticks {R}hipicephalus sanguineus. {T}he skin thus constitutes an important barrier for the entry and propagation of {R}. conorii. {G}iven this, analysis of the survival strategies used by the bacterium within infected skin is critical for our understanding of rickettsiosis. {M}ethodology/{P}rincipal {F}indings: {H}ere, we report the first genome-wide analysis of {R}. conorii gene expression from infected human skin biopsies. {O}ur data showed that {R}. conorii exhibited a striking transcript signature that is remarkably conserved across patients, regardless of genotype. {T}he expression profiles obtained using custom {A}gilent microarrays were validated by quantitative {RT}-{PCR}. {W}ithin eschars, the amount of detected {R}. conorii transcripts was of 55%, this value being of 74% for bacteria grown in {V}ero cells. {I}n such infected host tissues, approximately 15% (n = 211) of the total predicted {R}. conorii {ORF}s appeared differentially expressed compared to bacteria grown in standard laboratory conditions. {T}hese genes are mostly down-regulated and encode proteins essential for bacterial replication. {S}ome of the strategies displayed by rickettsiae to overcome the host defense barriers, thus avoiding killing, were also pointed out. {T}he observed up-regulation of rickettsial genes associated with {DNA} repair is likely to correspond to a {DNA}-damaging agent enriched environment generated by the host cells to eradicate the pathogens. {S}urvival of {R}. conorii within eschars also involves adaptation to osmotic stress, changes in cell surface proteins and up-regulation of some virulence factors. {I}nterestingly, in contrast to down-regulated transcripts, we noticed that up-regulated ones rather exhibit a small nucleotide size, most of them being exclusive for the spotted fever group rickettsiae. {C}onclusion/{S}ignificance: {B}ecause eschar is a site for rickettsial introduction, the pattern of rickettsial gene expression observed here may define how rickettsiae counteract the host defense.},
  keywords = {},
  booktitle = {},
  journal = {{P}los {O}ne},
  volume = {3},
  numero = {11},
  pages = {e3681},
  ISSN = {1932-6203},
  year = {2008},
  DOI = {10.1371/journal.pone.0003681},
  URL = {https://www.documentation.ird.fr/hor/fdi:010048496},
}