New Insights into the Composition and Function of the Cytoskeleton in Giardia lamblia and Trichomonas vaginalis
Heidi G. Elmendorf, Richard D. Hayes, Shweta Srivastava and Patricia Johnson
from: Anaerobic Parasitic Protozoa: Genomics and Molecular Biology (Edited by: C. Graham Clark, Patricia J. Johnson and Rodney D. Adam). Caister Academic Press, U.K. (2010)
In this chapter, we discuss insights the recent publication of the Giardia lamblia and Trichomonas vaginalis genome projects have brought to our understanding of the unique cytoskeletal protein profiles of these two parasites and integrate this new analysis of protein composition with recent structural and functional studies. Although both parasites are flagellated, the differences in both the structural and protein composition of their cytoskeletons are more numerous than their similarities. Consistent with general patterns across its genome, the cytoskeletal gene families in Trichomonas are greatly amplified in number, while the corresponding families in Giardia are - with few exceptions - represented by only one or a very few copies. While the microfilament proteome is largely complete in Trichomonas, it is virtually absent in Giardia. Thus, when similarities between the two cytoskeletons emerge, they are all the more notable. Perhaps most striking is the fact that while the dynein and kinesin motor families are well-represented in both parasites, there is an apparent absence of myosins in both, with no clear evidence of a functional substitute or altered basis for microfilament dynamics read more ...