This Article Full Text Full Text (PDF) Supplemental material Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Beck, D. L. Articles by Petri, W. A. Search for Related Content PubMed PubMed Citation Articles by Beck, D. L. Articles by Petri, W. A., Jr.

Identification and Gene Expression Analysis of a Large Family of Transmembrane Kinases Related to the Gal/GalNAc Lectin in Entamoeba histolytica

David L. Beck,^1, Douglas R. Boettner,¹ Bojan Dragulev,¹ Kim Ready,^2,3 Tomoyoshi Nozaki,^4,5 and William A. Petri Jr.^1,2,3*

Departments of Microbiology,¹ Medicine,² Pathology, University of Virginia, Charlottesville, Virginia 22908-1340,³ Department of Parasitology, National Institute of Infectious Diseases, Tokyo 162-8640,⁴ Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, 2-20-5 Akebonocho, Tachikawa, Tokyo 190-0012, Japan⁵

Received 22 November 2004/ Accepted 9 February 2005

We identified in the Entamoeba histolytica genome a family of over 80 putative transmembrane kinases (TMKs). The TMK extracellular domains had significant similarity to the intermediate subunit (Igl) of the parasite Gal/GalNAc lectin. The closest homolog to the E. histolytica TMK kinase domain was a cytoplasmic dual-specificity kinase, SplA, from Dictyostelium discoideum. Sequence analysis of the TMK family demonstrated similarities to both serine/threonine and tyrosine kinases. TMK genes from each of six phylogenetic groups were expressed as mRNA in trophozoites, as assessed by spotted oligoarray and real-time PCR assays, suggesting nonredundant functions of the TMK groups for sensing and responding to extracellular stimuli. Additionally, we observed changes in the expression profile of the TMKs in continuous culture. Antisera produced against the conserved kinase domain identified proteins of the expected molecular masses of the expressed TMKs. Confocal microscopy with anti-TMK kinase antibodies revealed a focal distribution of the TMKs on the cytoplasmic face of the trophozoite plasma membrane. We conclude that E. histolytica expresses members of each subgroup of TMKs. The presence of multiple receptor kinases in the plasma membrane offers for the first time a potential explanation of the ability of the parasite to respond to the changing environment of the host.

Supplemental material for this article may be found at http://ec.asm.org/.

Present address: Department of Biology and Chemistry, Texas A&M International University, 5201 University Blvd., Laredo, TX 78041-1900.

This article has been cited by other articles:

• Morrison, H. G., McArthur, A. G., Gillin, F. D., Aley, S. B., Adam, R. D., Olsen, G. J., Best, A. A., Cande, W. Z., Chen, F., Cipriano, M. J., Davids, B. J., Dawson, S. C., Elmendorf, H. G., Hehl, A. B., Holder, M. E., Huse, S. M., Kim, U. U., Lasek-Nesselquist, E., Manning, G., Nigam, A., Nixon, J. E. J., Palm, D., Passamaneck, N. E., Prabhu, A., Reich, C. I., Reiner, D. S., Samuelson, J., Svard, S. G., Sogin, M. L. (2007). Genomic Minimalism in the Early Diverging Intestinal Parasite Giardia lamblia. Science 317: 1921-1926 [Abstract] [Full Text]  
• Mehra, A., Fredrick, J., Petri, W. A. Jr., Bhattacharya, S., Bhattacharya, A. (2006). Expression and Function of a Family of Transmembrane Kinases from the Protozoan Parasite Entamoeba histolytica. Infect. Immun. 74: 5341-5351 [Abstract] [Full Text]  
• Frederick, J. R., Petri, W. A. Jr. (2005). Roles for the galactose-/N-acetylgalactosamine-binding lectin of Entamoeba in parasite virulence and differentiation. Glycobiology 15: 53R-59R [Abstract] [Full Text]