Project description:RNASequencing and RNA level measurements of G. lamblia transcripts during trophozite stage to compare expression between genes of interest
Project description:Giardia lamblia is one of most common agents causing persistent abdominal symptoms in developed and developing countries. There are several diagnostic methods for Giardia infection, but none are optimal. In this study our aim was to find a new method based on Giardia microRNA (miRNA) that would contribute to the currently available diagnostic methods of giardiasis. Profiling Giardia small RNAs by deep sequencing revealed that the previously reported putative miR5 and miR6 are expressed in several G. lamblia isolates. These miRNAs were later tested by PCR in duodenal biopsies from 8 patients with positive pathology for giardiasis, while gastric biopsies served as matched negative controls. Additionally, these miRNAs were evaluated in stool samples of patients with proven giardiasis. All 8 duodenal samples of patients with histologically proven G. lamblia infection were positive for Giardia miR5 with a mean Ct of 23.7. These results were superior to Ct levels of G. lamblia DNA, which were 26.3 (p=0.004). The miR6 results were close to negative. All 10 gastric biopsies were negative for miR5. Stool studies showed 90% specificity but only 50% sensitivity in diagnosing giardiasis using miR6. The results of miR5 in stool were even less accurate. In conclusion, miR5 testing for Giardia infection in duodenal biopsies, may be a breakthrough method for diagnosis of giardiasis. It seems to be superior to G. lamblia DNA in duodenal biopsies. It would be important to investigate the contribution of routine Giardia miRNA testing in duodenal biopsies and duodenal aspirates from patients with persistent abdominal symptoms.
Project description:Transcriptional profiling of Giardia lamblia WB comparing control 5'5npac cells with pPMBF1 cells. Multiprotein bridging factor 1 (MBF1) gene family proteins are involved in cell growth and differentiation in various organisms. We asked whether Giardia MBF1-like protein can induce various endogenous genes. We used epitope-tagged system to overexpress Giardia MBF1 by constructing and transfecting pPMBF1, a plasmid for expressing MBF1, to trophozoites. The control cell line is 5'5npac cell line, which expressed only the puromycin selection marker. To understand the effect of MBF1 overexpression on transcription profiles, we performed microarray analysis for pPMBF1 and 5'5npac cell lines.