|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Journal of Cell Science, Vol 113, Issue 12 2243-2252, Copyright © 2000 by Company of Biologists
JOURNAL ARTICLES |
B Shiels, M Fox, S McKellar, J Kinnaird and D Swan
Department of Veterinary Parasitology, University of Glasgow, Glasgow, G61 1QH, UK. B.Shiels@vet.gla.ac.uk
Apicomplexan parasites are major pathogens of humans and domesticated animals. A fundamental aspect of apicomplexan biology, which may provide novel molecular targets for parasite control, is the regulation of stage differentiation. Studies carried out on Theileria annulata, a bovine apicomplexan parasite, have provided evidence that a stochastic process controls differentiation from the macroschizont to the merozoite stage. It was postulated that this process involves the presence of regulators of merozoite gene expression in the preceding stage of the life cycle, and that during differentiation a quantitative increase of these factors occurs. This study was carried out to test these postulations. Nuclear run-on analysis showed that TamS1 expression is controlled, at least in part, at the transcriptional level. The transcription start site showed homology with the consensus eukaryotic initiator motif, and study of the 5' upstream region by the electrophoretic mobility-shift assay demonstrated that a 23 bp motif specifically bound factors from parasite-enriched nuclear extracts. Three complexes were shown to bind to a 9 bp core binding site (5'-TTTGTAGGG-3'). Two of these complexes were present in macroschizont extracts but were found at elevated levels during differentiation. Both complexes contain a polypeptide of the same molecular mass and may be related via the formation of homodimer or heterodimer complexes. The third complex appears to be distinct and was detected at time points associated with the transition to high level merozoite gene expression.
This article has been cited by other articles:
![]() |
B. R. Shiels, S. McKellar, F. Katzer, K. Lyons, J. Kinnaird, C. Ward, J. M. Wastling, and D. Swan A Theileria annulata DNA Binding Protein Localized to the Host Cell Nucleus Alters the Phenotype of a Bovine Macrophage Cell Line Eukaryot. Cell, April 1, 2004; 3(2): 495 - 505. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. G. Swan, R. Stern, S. McKellar, K. Phillips, C. A. L. Oura, T. I. Karagenc, L. Stadler, and B. R. Shiels Characterisation of a cluster of genes encoding Theileria annulata AT hook DNA-binding proteins and evidence for localisation to the host cell nucleus J. Cell Sci., January 8, 2001; 114(15): 2747 - 2754. [Abstract] [Full Text] [PDF] |
||||