Molecular cloning of a rhoptry protein (ROP6) secreted from Toxoplasma gondii

  • Ahn Hye-Jin (Department of Parasitology and the Catholic Institute of Parasitic Diseases, College of Medicine, Catholic University of Korea) ;
  • Kim Seh-Ra (Department of Parasitology and the Catholic Institute of Parasitic Diseases, College of Medicine, Catholic University of Korea) ;
  • Nam Ho-Woo (Department of Parasitology and the Catholic Institute of Parasitic Diseases, College of Medicine, Catholic University of Korea)
  • Published : 2006.09.01

Abstract

Monoclonal antibody (mAb) Tg786 against Toxoplasma gondii has been found to detect a 42-kDa rhoptry protein (ROP6) which showed protease activity and host cell binding characteristics after secretion. Using the mAb, a colony containing a 3'-UTR was probed in a T. gondii cDNA expression library. A full length cDNA sequence of the rhoptry protein was completed after 5'-RACE, which consisted of 1,908 bp with a 1,443 bp ORF. The deduced amino acid sequence of ROP6 consisted of a polypeptide of 480 amino acids without significant homology to any other known proteins. This sequence contains an amino terminal stop transfer sequence downstream of a short neutral sequence, hydrophilic middle sequence, and hydrophobic carboxy terminus. It is suggested that the ROP6 is inserted into the rhoptry membrane with both N- and C-termini.

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References

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