Change search
ReferencesLink to record
Permanent link

Direct link
Time-Dependent Transcriptional Changes in Axenic Giardia duodenalis Trophozoites
Univ Melbourne, Fac Vet & Agr Sci, Parkville, Vic 3052, Australia..
Univ Melbourne, Mol Sci & Biotechnol Inst Bio21, Parkville, Vic 3052, Australia..
Univ Melbourne, Fac Vet & Agr Sci, Parkville, Vic 3052, Australia..
Univ Melbourne, Fac Vet & Agr Sci, Parkville, Vic 3052, Australia..
Show others and affiliations
2015 (English)In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 9, no 12, e0004261Article in journal (Refereed) PublishedText
Abstract [en]

Giardia duodenalis is the most common gastrointestinal protozoan parasite of humans and a significant contributor to the global burden of both diarrheal disease and post-infectious chronic disorders. Although G. duodenalis can be cultured axenically, significant gaps exist in our understanding of the molecular biology and metabolism of this pathogen. The present study employed RNA sequencing to characterize the mRNA transcriptome of G. duodenalis trophozoites in axenic culture, at log (48 h of growth), stationary (60 h), and declining (96 h) growth phases. Using similar to 400-times coverage of the transcriptome, we identified 754 differentially transcribed genes (DTGs), mainly representing two large DTG groups: 438 that were down-regulated in the declining phase relative to log and stationary phases, and 281 that were up-regulated. Differential transcription of prominent antioxidant and glycolytic enzymes implicated oxygen tension as a key factor influencing the transcriptional program of axenic trophozoites. Systematic bioinformatic characterization of numerous DTGs encoding hypothetical proteins of unknown function was achieved using structural homology searching. This powerful approach greatly informed the differential transcription analysis and revealed putative novel antioxidant-coding genes, and the presence of a nearcomplete two-component-like signaling system that may link cytosolic redox or metabolite sensing to the observed transcriptional changes. Motif searching applied to promoter regions of the two large DTG groups identified different putative transcription factor-binding motifs that may underpin global transcriptional regulation. This study provides new insights into the drivers and potential mediators of transcriptional variation in axenic G. duodenalis and provides context for static transcriptional studies.

Place, publisher, year, edition, pages
2015. Vol. 9, no 12, e0004261
National Category
Infectious Medicine
URN: urn:nbn:se:uu:diva-277895DOI: 10.1371/journal.pntd.0004261ISI: 000368345100036OAI: diva2:906990
Available from: 2016-02-25 Created: 2016-02-23 Last updated: 2016-02-25Bibliographically approved

Open Access in DiVA

fulltext(2080 kB)103 downloads
File information
File name FULLTEXT01.pdfFile size 2080 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Svärd, Staffan G.
By organisation
In the same journal
PLoS Neglected Tropical Diseases
Infectious Medicine

Search outside of DiVA

GoogleGoogle Scholar
Total: 103 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 275 hits
ReferencesLink to record
Permanent link

Direct link