High‐resolution transcriptional analysis of the regulatory influence of cell‐to‐cell signalling reveals novel genes that contribute to Xanthomonas phytopathogenesis. Issue 6 (26th April 2013)

• Record Type: Journal Article
• Authors: An, Shi‐Qi; Febrer, Melanie; McCarthy, Yvonne; Tang, Dong‐Jie; Clissold, Leah; Kaithakottil, Gemy; Swarbreck, David; Tang, Ji‐Liang; Rogers, Jane; Dow, J. Maxwell; Ryan, Robert P.
• Is Part Of: Molecular microbiology. Volume 88:Issue 6(2013)
• Page Start: 1058
• Page End: 1069
• Publication Date: 2013-04-26
• Subjects: Molecular microbiology -- Periodicals; 572.829
• DOI: 10.1111/mmi.12229
• Languages: English
• ISSNs: 0950-382X

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>The bacterium <italic>Xanthomonas campestris</italic> is an economically important pathogen of many crop species and a model for the study of bacterial phytopathogenesis. In <italic>X. campestris</italic>, a regulatory system mediated by the signal molecule DSF controls virulence to plants. The synthesis and recognition of the DSF signal depends upon different Rpf proteins. DSF signal generation requires RpfF whereas signal perception and transduction depends upon a system comprising the sensor RpfC and regulator RpfG. Here we have addressed the action and role of Rpf/DSF signalling in phytopathogenesis by high‐resolution transcriptional analysis coupled to functional genomics. We detected transcripts for many genes that were unidentified by previous computational analysis of the genome sequence. Novel transcribed regions included intergenic transcripts predicted as coding or non‐coding as well as those that were antisense to coding sequences. In total, mutation of <italic>rpfF</italic>, <italic>rpfG</italic> and <italic>rpfC</italic> led to alteration in transcript levels (more than fourfold) of approximately 480 genes. The regulatory influence of RpfF and RpfC demonstrated considerable overlap. Contrary to expectation, the regulatory influence of RpfC and RpfG had limited overlap, indicating complexities of the Rpf signalling system. Importantly, functional analysis revealed over 160 new virulence factors within the group of Rpf‐regulated genes.</p> </abstract>