Analysis of the dermatophyte Trichophyton rubrum expressed sequence tags

BACKGROUND: Dermatophytes are the primary causative agent of dermatophytoses, a disease that affects billions of individuals worldwide. Trichophyton rubrum is the most common of the superficial fungi. Although T. rubrum is a recognized pathogen for humans, little is known about how its transcriptional pattern is related to development of the fungus and establishment of disease. It is therefore necessary to identify genes whose expression is relevant to growth, metabolism and virulence of T. rubrum. RESULTS: We generated 10 cDNA libraries covering nearly the entire growth phase and used them to isolate 11,085 unique expressed sequence tags (ESTs), including 3,816 contigs and 7,269 singletons. Comparisons with the GenBank non-redundant (NR) protein database revealed putative functions or matched homologs from other organisms for 7,764 (70%) of the ESTs. The remaining 3,321 (30%) of ESTs were only weakly similar or not similar to known sequences, suggesting that these ESTs represent novel genes. CONCLUSION: The present data provide a comprehensive view of fungal physiological processes including metabolism, sexual and asexual growth cycles, signal transduction and pathogenic mechanisms

The use of global transcriptional analysis to reveal the biological and cellular events involved in distinct development phases of Trichophyton rubrum conidial germination

<p>Abstract</p> <p>Background</p> <p>Conidia are considered to be the primary cause of infections by <it>Trichophyton rubrum</it>.</p> <p>Results</p> <p>We have developed a cDNA microarray containing 10250 ESTs to monitor the transcriptional strategy of conidial germination. A total of 1561 genes that had their expression levels specially altered in the process were obtained and hierarchically clustered with respect to their expression profiles. By functional analysis, we provided a global view of an important biological system related to conidial germination, including characterization of the pattern of gene expression at sequential developmental phases, and changes of gene expression profiles corresponding to morphological transitions. We matched the EST sequences to GO terms in the <it>Saccharomyces </it>Genome Database (SGD). A number of homologues of <it>Saccharomyces cerevisiae </it>genes related to signalling pathways and some important cellular processes were found to be involved in <it>T. rubrum </it>germination. These genes and signalling pathways may play roles in distinct steps, such as activating conidial germination, maintenance of isotropic growth, establishment of cell polarity and morphological transitions.</p> <p>Conclusion</p> <p>Our results may provide insights into molecular mechanisms of conidial germination at the cell level, and may enhance our understanding of regulation of gene expression related to the morphological construction of <it>T. rubrum</it>.</p

Functional reorganization of intranetwork and internetwork connectivity in patients with Ménière’s disease

Abstract Ménière’s disease (MD) is associated with functional reorganization not only in the auditory or sensory cortex but also in other control and cognitive areas. In this study, we examined intranetwork and internetwork connectivity differences between 55 MD patients and 70 healthy controls (HC) in 9 well-defined resting-state networks. Functional connectivity degree was lower in MD compared to HC in 19 brain areas involved in the somatomotor, auditory, ventral attention, default mode, limbic, and deep gray matter networks. In addition, we observed lower intranetwork connectivity in the auditory, ventral attention, and limbic networks, as well as lower internetwork connectivity between the somatomotor and limbic networks, and between the auditory and somatomotor, deep gray matter, and ventral attention networks, and between the deep gray matter and default mode network. Furthermore, we identified 81 pairs of brain areas with significant differences in functional connectivity between MD patients and HC at the edge level. Notably, the left amygdala’s functional connectivity degree was positively correlated with MD’s disease stage, and the ventral attention network’s intranetwork connectivity was positively correlated with the healthy side vestibular ratio. Our findings suggest that these functional network reorganization alterations may serve as potential biomarkers for predicting clinical progression, evaluating disease severity, and gaining a better understanding of MD’s pathophysiology. Large-scale network studies using neuroimaging techniques can provide additional insights into the underlying mechanisms of MD

Transcriptional Profiles of the Response to Ketoconazole and Amphotericin B in Trichophyton rubrum

Trichophyton rubrum is a pathogenic filamentous fungus of increasing medical concern. Two antifungal agents, ketoconazole (KTC) and amphotericin B (AMB), have specific activity against dermatophytes. To identify the mechanisms of action of KTC and AMB against T. rubrum, a cDNA microarray was constructed from the expressed sequence tags of the cDNA library from different developmental stages, and transcriptional profiles of the responses to KTC and AMB were determined. T. rubrum was exposed to subinhibitory concentrations of KTC and AMB for 12 h, and microarray analysis was used to examine gene transcription. KTC exposure induced transcription of genes involved in lipid, fatty acid, and sterol metabolism, including ERG11, ERG3, ERG25, ERG6, ERG26, ERG24, ERG4, CPO, INO1, DW700960, CPR, DW696584, DW406350, and ATG15. KTC also increased transcription of the multidrug resistance gene ABC1. AMB exposure increased transcription of genes involved in lipid, fatty acid, and sterol metabolism (DW696584, EB801458, IVD, DW694010, DW688343, DW684992), membrane transport (Git1, DW706156, DW684040, DMT, DW406136, CCH1, DW710650), and stress-related responses (HSP70, HSP104, GSS, AOX, EB801455, EB801702, TDH1, UBI4) but reduced transcription of genes involved in maintenance of cell wall integrity and signal transduction pathways (FKS1, SUN4, DW699324, GAS1, DW681613, SPS1, DW703091, STE7, DW703091, DW695308) and some ribosomal proteins. This is the first report of the use of microarray analysis to determine the effects of drug action in T. rubrum

The use of global transcriptional analysis to reveal the biological and cellular events involved in distinct development phases of conidial germination-0

<p><b>Copyright information:</b></p><p>Taken from "The use of global transcriptional analysis to reveal the biological and cellular events involved in distinct development phases of conidial germination"</p><p>http://www.biomedcentral.com/1471-2164/8/100</p><p>BMC Genomics 2007;8():100-100.</p><p>Published online 11 Apr 2007</p><p>PMCID:PMC1871584.</p><p></p> indicated time-points, and show the morphological transitions with time