Abstract
Null mutants of the Trypanosoma cruzi insect stage-specific glycoprotein GP72 were created by targeted gene replacement. Targeting plasmids were constructed in which the neomycin phosphotransferase and hygromycin phosphotransferase genes were flanked by GP72 sequences. These plasmids were sequentially transfected into T. cruzi epimastigotes by electroporation. Southern blot analyzes indicated that precise replacement of the two genes had occurred. No aberrant rearrangements occurred at the GP72 locus and no GP72 gene sequences had been translocated elsewhere in the genome. Western blots confirmed that GP72 is not expressed in these null mutants. The morphology of the mutants is dramatically different from wild-type. In both mutant and wild-type parasites, the flagellum emerges from the flagellar pocket. In the null mutant the normal attachment of the flagellum to the cell membrane of the parasite is lost.
Full Text
The Full Text of this article is available as a PDF (2.6 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Andrews N. W., Hong K. S., Robbins E. S., Nussenzweig V. Stage-specific surface antigens expressed during the morphogenesis of vertebrate forms of Trypanosoma cruzi. Exp Parasitol. 1987 Dec;64(3):474–484. doi: 10.1016/0014-4894(87)90062-2. [DOI] [PubMed] [Google Scholar]
- Bellofatto V., Cross G. A. Expression of a bacterial gene in a trypanosomatid protozoan. Science. 1989 Jun 9;244(4909):1167–1169. doi: 10.1126/science.2499047. [DOI] [PubMed] [Google Scholar]
- Bellofatto V. The new trypanosomatid genetics. Parasitol Today. 1990 Sep;6(9):299–302. doi: 10.1016/0169-4758(90)90260-b. [DOI] [PubMed] [Google Scholar]
- Bradley J. E., Gregory W. F., Bianco A. E., Maizels R. M. Biochemical and immunochemical characterisation of a 20-kilodalton complex of surface-associated antigens from adult Onchocerca gutturosa filarial nematodes. Mol Biochem Parasitol. 1989 May 15;34(3):197–208. doi: 10.1016/0166-6851(89)90048-0. [DOI] [PubMed] [Google Scholar]
- Capecchi M. R. Altering the genome by homologous recombination. Science. 1989 Jun 16;244(4910):1288–1292. doi: 10.1126/science.2660260. [DOI] [PubMed] [Google Scholar]
- Capecchi M. Gene targeting. How efficient can you get? Nature. 1990 Nov 8;348(6297):109–109. doi: 10.1038/348109a0. [DOI] [PubMed] [Google Scholar]
- Clayton C. E., Fueri J. P., Itzhaki J. E., Bellofatto V., Sherman D. R., Wisdom G. S., Vijayasarathy S., Mowatt M. R. Transcription of the procyclic acidic repetitive protein genes of Trypanosoma brucei. Mol Cell Biol. 1990 Jun;10(6):3036–3047. doi: 10.1128/mcb.10.6.3036. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooper R., Inverso J. A., Espinosa M., Nogueira N., Cross G. A. Characterization of a candidate gene for GP72, an insect stage-specific antigen of Trypanosoma cruzi. Mol Biochem Parasitol. 1991 Nov;49(1):45–59. doi: 10.1016/0166-6851(91)90129-t. [DOI] [PubMed] [Google Scholar]
- Cotrim P. C., Paranhos G. S., Mortara R. A., Wanderley J., Rassi A., Camargo M. E., da Silveira J. F. Expression in Escherichia coli of a dominant immunogen of Trypanosoma cruzi recognized by human chagasic sera. J Clin Microbiol. 1990 Mar;28(3):519–524. doi: 10.1128/jcm.28.3.519-524.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cruz A., Beverley S. M. Gene replacement in parasitic protozoa. Nature. 1990 Nov 8;348(6297):171–173. doi: 10.1038/348171a0. [DOI] [PubMed] [Google Scholar]
- Cruz A., Coburn C. M., Beverley S. M. Double targeted gene replacement for creating null mutants. Proc Natl Acad Sci U S A. 1991 Aug 15;88(16):7170–7174. doi: 10.1073/pnas.88.16.7170. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Souza W., Martínez-Palomo A., González-Robles A. The cell surface of Trypanosoma cruzi: cytochemistry and freeze-fracture. J Cell Sci. 1978 Oct;33:285–299. doi: 10.1242/jcs.33.1.285. [DOI] [PubMed] [Google Scholar]
- Eid J., Sollner-Webb B. Stable integrative transformation of Trypanosoma brucei that occurs exclusively by homologous recombination. Proc Natl Acad Sci U S A. 1991 Mar 15;88(6):2118–2121. doi: 10.1073/pnas.88.6.2118. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ferguson M. A., Allen A. K., Snary D. Studies on the structure of a phosphoglycoprotein from the parasitic protozoan Trypanosoma cruzi. Biochem J. 1983 Aug 1;213(2):313–319. doi: 10.1042/bj2130313. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Garcia E. S., Azambuja P. Development and interactions of Trypanosoma cruzi within the insect vector. Parasitol Today. 1991 Sep;7(9):240–244. doi: 10.1016/0169-4758(91)90237-i. [DOI] [PubMed] [Google Scholar]
- Hariharan S., Ajioka J., Swindle J. Stable transformation of Trypanosoma cruzi: inactivation of the PUB12.5 polyubiquitin gene by targeted gene disruption. Mol Biochem Parasitol. 1993 Jan;57(1):15–30. doi: 10.1016/0166-6851(93)90240-x. [DOI] [PubMed] [Google Scholar]
- Harth G., Mills A. A., Souto-Padrón T., de Souza W. Trypanosoma cruzi glycoprotein 72: immunological analysis and cellular localization. Mol Cell Biochem. 1992 Jan 15;109(1):25–36. doi: 10.1007/BF00230870. [DOI] [PubMed] [Google Scholar]
- Hogan J. C., Jr, Patton C. L. Variation in intramembrane components of Trypanosoma brucei from intact and x-irradiated rats: a freeze-cleave study. J Protozool. 1976 May;23(2):205–215. doi: 10.1111/j.1550-7408.1976.tb03757.x. [DOI] [PubMed] [Google Scholar]
- Ibañez C. F., Affranchino J. L., Frasch A. C. Antigenic determinants of Trypanosoma cruzi defined by cloning of parasite DNA. Mol Biochem Parasitol. 1987 Sep;25(2):175–184. doi: 10.1016/0166-6851(87)90006-5. [DOI] [PubMed] [Google Scholar]
- Ibañez C. F., Affranchino J. L., Macina R. A., Reyes M. B., Leguizamon S., Camargo M. E., Aslund L., Pettersson U., Frasch A. C. Multiple Trypanosoma cruzi antigens containing tandemly repeated amino acid sequence motifs. Mol Biochem Parasitol. 1988 Jul;30(1):27–33. doi: 10.1016/0166-6851(88)90129-6. [DOI] [PubMed] [Google Scholar]
- Kirchhoff L. V., Hieny S., Shiver G. M., Snary D., Sher A. Cryptic epitope explains the failure of a monoclonal antibody to bind to certain isolates of Trypanosoma cruzi. J Immunol. 1984 Nov;133(5):2731–2735. [PubMed] [Google Scholar]
- Laban A., Wirth D. F. Transfection of Leishmania enriettii and expression of chloramphenicol acetyltransferase gene. Proc Natl Acad Sci U S A. 1989 Dec;86(23):9119–9123. doi: 10.1073/pnas.86.23.9119. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lake J. A., de la Cruz V. F., Ferreira P. C., Morel C., Simpson L. Evolution of parasitism: kinetoplastid protozoan history reconstructed from mitochondrial rRNA gene sequences. Proc Natl Acad Sci U S A. 1988 Jul;85(13):4779–4783. doi: 10.1073/pnas.85.13.4779. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lee M. G., Van der Ploeg L. H. Homologous recombination and stable transfection in the parasitic protozoan Trypanosoma brucei. Science. 1990 Dec 14;250(4987):1583–1587. doi: 10.1126/science.2177225. [DOI] [PubMed] [Google Scholar]
- Lu H. Y., Buck G. A. Expression of an exogenous gene in Trypanosoma cruzi epimastigotes. Mol Biochem Parasitol. 1991 Jan;44(1):109–114. doi: 10.1016/0166-6851(91)90226-v. [DOI] [PubMed] [Google Scholar]
- Müller N., Hemphill A., Imboden M., Duvallet G., Dwinger R. H., Seebeck T. Identification and characterization of two repetitive non-variable antigens from African trypanosomes which are recognized early during infection. Parasitology. 1992 Feb;104(Pt 1):111–120. doi: 10.1017/s0031182000060856. [DOI] [PubMed] [Google Scholar]
- Nogueira N., Chaplan S., Tydings J. D., Unkeless J., Cohn Z. Trypanosoma cruzi. Surface antigens of blood and culture forms. J Exp Med. 1981 Mar 1;153(3):629–639. doi: 10.1084/jem.153.3.629. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Otsu K., Donelson J. E., Kirchhoff L. V. Interruption of a Trypanosoma cruzi gene encoding a protein containing 14-amino acid repeats by targeted insertion of the neomycin phosphotransferase gene. Mol Biochem Parasitol. 1993 Feb;57(2):317–330. doi: 10.1016/0166-6851(93)90207-e. [DOI] [PubMed] [Google Scholar]
- Rudenko G., Le Blancq S., Smith J., Lee M. G., Rattray A., Van der Ploeg L. H. Procyclic acidic repetitive protein (PARP) genes located in an unusually small alpha-amanitin-resistant transcription unit: PARP promoter activity assayed by transient DNA transfection of Trypanosoma brucei. Mol Cell Biol. 1990 Jul;10(7):3492–3504. doi: 10.1128/mcb.10.7.3492. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schechter M., Stevens A. F., Luquetti A. O., Snary D., Allen A. K., Miles M. A. Prevalence of antibodies to 72-kilodalton glycoprotein (GP72) in patients with Chagas' disease and further evidence of zymodeme-associated expression of GP72 carbohydrate epitopes. Infect Immun. 1986 Sep;53(3):547–552. doi: 10.1128/iai.53.3.547-552.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sher A., Snary D. Specific inhibition of the morphogenesis of Trypanosoma cruzi by a monoclonal antibody. Nature. 1982 Dec 16;300(5893):639–640. doi: 10.1038/300639a0. [DOI] [PubMed] [Google Scholar]
- Snary D., Ferguson M. A., Scott M. T., Allen A. K. Cell surface antigens of Trypanosoma cruzi: use of monoclonal antibodies to identify and isolate an epimastigote specific glycoprotein. Mol Biochem Parasitol. 1981 Oct;3(6):343–356. doi: 10.1016/0166-6851(81)90035-9. [DOI] [PubMed] [Google Scholar]
- Souto-Padrón T., Reyes M. B., Leguizamon S., Campetella O. E., Frasch A. C., de Souza W. Trypanosoma cruzi proteins which are antigenic during human infections are located in defined regions of the parasite. Eur J Cell Biol. 1989 Dec;50(2):272–278. [PubMed] [Google Scholar]
- Vickerman K. On the surface coat and flagellar adhesion in trypanosomes. J Cell Sci. 1969 Jul;5(1):163–193. doi: 10.1242/jcs.5.1.163. [DOI] [PubMed] [Google Scholar]
- Woods A., Baines A. J., Gull K. Evidence for a Mr 88,000 glycoprotein with a transmembrane association to a unique flagellum attachment region in Trypanosoma brucei. J Cell Sci. 1989 Jul;93(Pt 3):501–508. doi: 10.1242/jcs.93.3.501. [DOI] [PubMed] [Google Scholar]
- Woods A., Sherwin T., Sasse R., MacRae T. H., Baines A. J., Gull K. Definition of individual components within the cytoskeleton of Trypanosoma brucei by a library of monoclonal antibodies. J Cell Sci. 1989 Jul;93(Pt 3):491–500. doi: 10.1242/jcs.93.3.491. [DOI] [PubMed] [Google Scholar]
- Zomerdijk J. C., Ouellette M., ten Asbroek A. L., Kieft R., Bommer A. M., Clayton C. E., Borst P. The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei. EMBO J. 1990 Sep;9(9):2791–2801. doi: 10.1002/j.1460-2075.1990.tb07467.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ten Asbroek A. L., Ouellette M., Borst P. Targeted insertion of the neomycin phosphotransferase gene into the tubulin gene cluster of Trypanosoma brucei. Nature. 1990 Nov 8;348(6297):174–175. doi: 10.1038/348174a0. [DOI] [PubMed] [Google Scholar]