title: CDPKs of Cryptosporidium parvum--stage-specific expression in vitro.
abstract: Cryptosporidium parvum is a zoonotic agent that bears a high risk for the health of particularly immunocompromised humans and animals. As currently available drugs and therapies against cryptosporidiosis do not turn out satisfactory, more intensive research on the control of this parasite is necessary. The genus Cryptosporidium is unique within the phylum Apicomplexa as its localisation is intracellular but extracytoplasmatic. Infection of host cells is initially a parasite-driven process, but the signalling events and their downstream actions within Cryptosporidium are poorly understood. Calcium-dependent protein kinases (CDPKs) are probably involved in the regulation of invasion and egress. Previously described in plants, algae and other Apicomplexa, CDPKs are not found in vertebrates. They are thus promising targets for pharmaceutical intervention. While CDPK1 is well characterised in Toxoplasma gondii (TgCDPK1) and Plasmodium falciparum (PfCDPK1), only little information exists about the expression and function of CDPK in C. parvum. Here, we describe results of the in silico analysis of seven CpCDPKs. Five CpCDPKs contain potential sites for N-myristoylation and N-palmitoylation. In a nested 3' rapid amplification of cDNA ends (RACE)-PCR, expression of six CpCDPKs resulted in distinct bands in infected cell cultures and extracts of freshly excysted sporozoites. The length of the 3' untranslated region (3' UTR) is described as well. Our results indicate CDPK expression to be stage specific on the mRNA level.
authors.affiliation: Institute of Parasitology, University of Leipzig, Leipzig, Germany, etzold@vetmed.uni-leipzig.de.
authors.forename: Manja
authors.initials: M
authors.lastname: Etzold
authors.forename: Matthias
authors.initials: M
authors.lastname: Lendner
authors.forename: Arwid
authors.initials: A
authors.lastname: Daugschies
authors.forename: Viktor
authors.initials: V
authors.lastname: Dyachenko
mesh_terms: D020413:3' Untranslated Regions; D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D016785:Cryptosporidium parvum / Q000201:enzymology / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D008969:Molecular Sequence Data; D019814:Myristic Acid / Q000378:metabolism; D019308:Palmitic Acid / Q000378:metabolism; D010802:Phylogeny; D010963:Plasmodium falciparum / Q000201:enzymology / Q000235:genetics; D016133:Polymerase Chain Reaction; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D015800:Protozoan Proteins / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D034101:Sporozoites / Q000737:chemistry / Q000201:enzymology*; D014122:Toxoplasma / Q000201:enzymology / Q000235:genetics; D017871:Calcium-Calmodulin-Dependent Protein Kinases
chemical_list: D020413:3' Untranslated Regions; D019814:Myristic Acid; D019308:Palmitic Acid; D011494:Protein Kinases; D015800:Protozoan Proteins; D017871:Calcium-Calmodulin-Dependent Protein Kinases