Trypanosoma congolense procyclins: unmasking cryptic major surface glycoproteins in procyclic forms

Utz, Silvia; Roditi, Isabel; Kunz Renggli, Christina; Almeida, Igor C; Acosta-Serrano, Alvaro; Bütikofer, Peter (2006). Trypanosoma congolense procyclins: unmasking cryptic major surface glycoproteins in procyclic forms. Eukaryotic cell, 5(8), pp. 1430-40. Washington, D.C.: American Society for Microbiology ASM 10.1128/EC.00067-06

Full text not available from this repository. (Request a copy)

In the tsetse fly, the protozoan parasite Trypanosoma congolense is covered by a dense layer of glycosylphosphatidylinositol (GPI)-anchored molecules. These include a protease-resistant surface molecule (PRS), which is expressed by procyclic forms early in infection, and a glutamic acid- and alanine-rich protein (GARP), which appears at later stages. Since neither of these surface antigens is expressed at intermediate stages, we investigated whether a GPI-anchored protein of 50 to 58 kDa, previously detected in procyclic culture forms, might constitute the coat of these parasites. We therefore partially purified the protein from T. congolense Kilifi procyclic forms, obtained an N-terminal amino acid sequence, and identified its gene. Detailed analyses showed that the mature protein consists almost exclusively of 13 heptapeptide repeats (EPGENGT). The protein is densely N glycosylated, with up to 13 high-mannose oligosaccharides ranging from Man(5)GlcNAc(2) to Man(9)GlcNAc(2) linked to the peptide repeats. The lipid moiety of the glycosylphosphatidylinositol is composed of sn-1-stearoyl-2-lyso-glycerol-3-HPO(4)-1-(2-O-acyl)-d-myo-inositol. Heavily glycosylated proteins with similar repeats were subsequently identified in T. congolense Savannah procyclic forms. Collectively, this group of proteins was named T. congolense procyclins to reflect their relationship to the EP and GPEET procyclins of T. brucei. Using an antiserum raised against the EPGENGT repeat, we show that T. congolense procyclins are expressed continuously in the fly midgut and thus form the surface coat of cells that are negative for both PRS and GARP.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Pre-clinic Human Medicine > Institute of Biochemistry and Molecular Medicine
08 Faculty of Science > Department of Biology > Institute of Cell Biology

UniBE Contributor:

Utz, Silvia; Roditi, Isabel and Bütikofer, Peter

ISSN:

1535-9778

Publisher:

American Society for Microbiology ASM

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 14:49

Last Modified:

06 Dec 2013 13:43

Publisher DOI:

10.1128/EC.00067-06

PubMed ID:

16896226

Web of Science ID:

000239778700024

URI:

https://boris.unibe.ch/id/eprint/20374 (FactScience: 3662)

Actions (login required)

Edit item Edit item
Provide Feedback