Abstract
Toxoplasma gondii isolates can be classified into mouse-virulent and -avirulent strains. Since the major surface antigen of Toxoplasma gondii, SAG1, has been shown to be important for the invasion process and might thus be involved in mouse virulence as well, we analyzed the corresponding gene of mouse-virulent and -avirulent strains. In addition to eight mismatches, mouse-virulent strains harbored five copies of an upstream 27-bp repeat in the promotor region of SAG1 as compared with four copies in avirulent strains. Reverse-transcriptase polymerase chain reaction revealed that SAG1 expression levels in the mouse-virulent T. gondii strains were at least 4-fold those in the avirulent strains. Since SAG1 seems to mediate invasion, it is suggested that the possibly higher steady-state expression of SAG1 in mouse-virulent strains of T. gondii is associated with virulence and facilitates faster invasion by these strains in comparison with avirulent strains.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 2 May 1996 / Accepted: 20 May 1996
Rights and permissions
About this article
Cite this article
Windeck, T., Gross, U. Toxoplasma gondii strain-specific transcript levels of SAG1 and their association with virulence. Parasitol Res 82, 715–719 (1996). https://doi.org/10.1007/s004360050190
Issue Date:
DOI: https://doi.org/10.1007/s004360050190