This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Mehra, A.
Right arrow Articles by Bhattacharya, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mehra, A.
Right arrow Articles by Bhattacharya, A.

 Previous Article  |  Next Article 

Infection and Immunity, September 2006, p. 5341-5351, Vol. 74, No. 9
0019-9567/06/$08.00+0     doi:10.1128/IAI.00025-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Expression and Function of a Family of Transmembrane Kinases from the Protozoan Parasite Entamoeba histolytica{dagger}

Alka Mehra,1 Jesse Fredrick,4 William A. Petri Jr.,4 Sudha Bhattacharya,2 and Alok Bhattacharya1,3*

School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India,1 School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India,2 School of Information Technology, Jawaharlal Nehru University, New Delhi-110067, India,3 Department of Medicine, University of Virginia, Charlottesville, Virginia4

Received 5 January 2006/ Returned for modification 7 March 2006/ Accepted 7 July 2006

The signaling proteome of Entamoeba histolytica is made of transmembrane kinases (TMKs) that are rarely found in unicellular eukaryotes. There are 90 TMK genes reported for E. histolytica, and these have been grouped into nine distinct families based on motifs present on both extracellular and kinase domains. Of these, the B1 family was chosen for further analysis. Genomic sequencing revealed the presence of 28 members belonging to this family. Genes corresponding to the majority of these were truncated and not considered for further analysis. Only five members were full length and contained both extracellular and cytosolic kinase domains. BLAST analysis revealed the presence of homologs of these B1 TMKs in the nonpathogenic Entamoeba dispar. However, the ligand binding domains of the orthologous B1 TMKs of the two species showed considerable divergence, indicating the possibility of a correlation with the pathogenic potential of the organism. Only two of the five full-length copies (B1.I.1 and B1.I.2) were expressed in E. histolytica under the culture conditions used. Antisera generated against the extracellular domain of B1.I.1 stained the cell surface, particularly the areas of contact between the trophozoites. Staining was also seen in the frontal and posterior regions of the motile amoeba. An amoebic cell line expressing a truncated version of the B1.I.1 that lacked the kinase domain was generated. Inducible expression of the truncated TMK resulted in a decrease in cellular proliferation and an increase in sensitivity to serum starvation. Our data indicate that the B1.I class of TMKs is involved in parasite proliferation.

* Corresponding author. Mailing address: Lab No. 117, School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India. Phone: 91 11 2670 4516. Fax: 91 11 2671 7586. E-mail: alok0200{at}mail.jnu.ac.in.

{dagger} Supplemental material for this article may be found at http://iai.asm.org/.

Editor: J. F. Urban, Jr.

Infection and Immunity, September 2006, p. 5341-5351, Vol. 74, No. 9
0019-9567/06/$08.00+0     doi:10.1128/IAI.00025-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»