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Differentially expressed parasite genes involved in host recognition and invasion of the triactinomyxon stage of Myxobolus cerebralis (Myxozoa)

  • E. ESZTERBAUER (a1) (a2), D. M. KALLERT (a1), D. GRABNER (a1) and M. EL-MATBOULI (a1)


The host recognition and invasion process of Myxobolus cerebralis actinospores (triactinomyxon, TAM) was studied on a genetic level. A small-scale in vitro assay was developed to activate a large number of TAMs simultaneously, and to monitor the host invasion in the absence of live fish. The transcriptomes of non-activated and in vitro-activated TAMs were compared by suppressive subtractive hybridization (SSH) to identify parasite genes involved in the host invasion process. Differential screening and a subsequent BLAST search revealed 15 of 452 SSH-library clones expressed differently in activated TAMs. None of the 15 transcripts obtained has previously been identified from M. cerebralis. Quantitative real-time PCR was used to examine the relative expression profile of 8 selected transcripts upon TAM activation and after penetration of the host. Four of these were found to be up-regulated in activated TAMs, while expression was relatively low in non-activated TAMs and in infected fish tissue, indicating that they are relevant genes during host recognition or subsequent host invasion of M. cerebralis TAMs.


Corresponding author

*Corresponding author: Clinic of Fish and Reptiles, Faculty of Veterinary Medicine, University of Munich, Kaulbachstraße 37, D-80539 Munich, Germany. Tel: +49 89 2180 3273. Fax: +49 89 280 5175. E-mail address:


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Differentially expressed parasite genes involved in host recognition and invasion of the triactinomyxon stage of Myxobolus cerebralis (Myxozoa)

  • E. ESZTERBAUER (a1) (a2), D. M. KALLERT (a1), D. GRABNER (a1) and M. EL-MATBOULI (a1)


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