Unknown,Transcriptomics,Genomics,Proteomics

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The pilus retraction protein PilT has a global influence on the transcriptome of Neisseria gonorrhoeae

ABSTRACT: The ATPase protein PilT mediates retraction of type IV pili. We performed microarrays comparing the transcription profile of the Neisseria gonorrhoeae wild-type strain MS11 and its isogenic pilT mutant. 63 open reading frames were found to be differentially regulated in the pilT mutant. Most interestingly, a loss of function mutation in pilT leads to an upregulation of pilE, which encodes the pilus subunit protein. Ngo arrays were generated as custom 8x15 K microarrays (Agilent Technologies) covering all open reading frames (ORFs) from N. gonorrhoeae strain FA1090 (accession number AE004969) supplemented with all ORFs from the gonoccoccal genetic island of strain MS11 (accession number AY803022) by 6 specific 60-mer oligonucleotides per gene on average. Microarray analysis was performed as dual-color hybridization with dye-reversal color-swaps as technical replicates for Cy-dye specific effect compensation and three independent biological replicates. Microarray features were extracted with the FE 9.5.3.1 software from Agilent Technologies using the GE2-v4_95_Feb07 protocol with default settings. Data were loaded into Resolver (Rosetta Biosoftware) using the MAGE-ML loader and analyzed for differential gene expression. Ratio profiles were combined into ratio experiments and regulated genes were identified with a threshold of 1.75 fold-change and anti-correlation of the color-swapped dye reversals, rendering the analysis highly stringent and robust with P values <0.0001 of the results.

ORGANISM(S): Neisseria gonorrhoeae

SUBMITTER: Hans-Joachim Mollenkopf

PROVIDER: E-GEOD-12258 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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The pilus retraction protein PilT has a global influence on the transcriptome of Neisseria gonorrhoeae

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