Structure and expression of three gp82 gene subfamilies of Trypanosoma cruzi

• Published in: Parasitology international Vol. 56; no. 4; pp. 273 - 280
• Main Authors: Songthamwat, Dujdow, Kajihara, Kazuo, Kikuchi, Mihoko, Uemura, Haruki, Phu Manh Tran, Sieu, Yanagi, Tetsuo, Higo, Hiroo, Hirayama, Kenji
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ireland Ltd 01.12.2007
• Subjects: 82-kDa glycoprotein; Amino Acid Sequence; Animals; Gastroenterology and Hepatology; Gene Expression Regulation; Guatemala; Humans; Infectious Disease; Metacyclic trypomastigote; Molecular Sequence Data; Multigene Family; Peru; Phosphoproteins - chemistry; Phosphoproteins - genetics; Phosphoproteins - metabolism; Phylogeny; Polymerase Chain Reaction; Protozoan Proteins - chemistry; Protozoan Proteins - genetics; Protozoan Proteins - metabolism; Real-time PCR; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Analysis, DNA; Trypanosoma cruzi; Trypanosoma cruzi - classification; Trypanosoma cruzi - genetics; Trypanosoma cruzi - growth & development; Trypanosoma cruzi - metabolism; Guatemala; Peru; GPI; gp82; Real-time PCR; surface glycoprotein 82 kDa; C T; Metacyclic trypomastigote; threshold cycle; Epithelial-like monkey kidney cell; glycosylphosphatidylinositol; 82-kDa glycoprotein; LLC-MK 2; Trypanosoma cruzi
• ISSN: 1383-5769; 1873-0329
• DOI: 10.1016/j.parint.2007.05.004

Abstract The glycoprotein gp82 is a GPI-anchored cell surface protein of Trypanosoma cruzi and is involved in cell invasion. Gp82 is encoded by multiple genes. To investigate the genetic basis of its biological function, we analyzed structure and expression of gp82 multigene family members in the Peruvian and Guatemalan strains. Three major groups of gp82 genes (A, B and C) were categorized by analyzing multiple DNA clones from the genomic PCR products. Within each group, 95–97% homology was observed, whereas between the groups, homology was 67–79%. The copy numbers of groups A, B and C as determined by real-time PCR were 18, 8 and 7 copies, respectively, in the Peru-2 strain. Significant elevation of the mRNA expression levels (5–10 times more) of all the subfamily genes was observed in the metacyclic stage compared with the epimastigote stage. When we focused on the binding motif sequence reported previously, we found substantial difference between that of A and C. However, the peptide inhibition invasion assay showed no functional difference. Taken together, we demonstrated that three subfamilies of gp82 were in the genome of T. cruzi and maintained their functional structure, and that the mRNA expressions of those genes were equally controlled in a stage-specific manner.