A Plasmodium falciparum Transcriptional Cyclin-Dependent Kinase-Related Kinase with a Crucial Role in Parasite Proliferation Associates with Histone Deacetylase Activity

INSERM-EPFL Joint Laboratory, Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, GHI-SV-EPFL,Lausanne, Switzerland.
Eukaryotic Cell (Impact Factor: 3.18). 03/2010; 9(6):952-9. DOI: 10.1128/EC.00005-10
Source: PubMed


Cyclin-dependent protein kinases (CDKs) are key regulators of the eukaryotic cell cycle and of the eukaryotic transcription machinery. Here we report the characterization of Pfcrk-3 (Plasmodium falciparum CDK-related kinase 3; PlasmoDB identifier PFD0740w), an unusually large CDK-related protein whose kinase domain displays maximal homology to those CDKs which, in other eukaryotes, are involved in the control of transcription. The closest enzyme in Saccharomyces cerevisiae is BUR1 (bypass upstream activating sequence requirement 1), known to control gene expression through interaction with chromatin modification enzymes. Consistent with this, immunofluorescence data show that Pfcrk-3 colocalizes with histones. We show that recombinant Pfcrk-3 associates with histone H1 kinase activity in parasite extracts and that this association is detectable even if the catalytic domain of Pfcrk-3 is rendered inactive by site-directed mutagenesis, indicating that Pfcrk-3 is part of a complex that includes other protein kinases. Immunoprecipitates obtained from extracts of transgenic parasites expressing hemagglutinin (HA)-tagged Pfcrk-3 by using an anti-HA antibody displayed both protein kinase and histone deacetylase activities. Reverse genetics data show that the pfcrk-3 locus can be targeted only if the genetic modification does not cause a loss of function. Taken together, our data strongly suggest that Pfcrk-3 fulfils a crucial role in the intraerythrocytic development of P. falciparum, presumably through chromatin modification-dependent regulation of gene expression.

  • Source
    • ") , Reininger et al . ( 2005 , 2009 , 2011 ) , Fennell et al . ( 2009 ) , Abdi et al . ( 2010 ) , Halbert et al . ( 2010 ) , Agarwal et al . ( 2011 ) ) . The Plasmodium ki - nome also includes many enzymes that do not cluster with any of the PK groups and families established from the yeast and mam - malian kinomes , such as the FIKK kinases , which are specific to api - complexan parasites ( Schneider and Mercereau - Puijalon , 2005 ) , and the CDPKs ( s"
    [Show abstract] [Hide abstract]
    ABSTRACT: Some apicomplexan parasites have evolved distinct protein kinase families to modulate host cell structure and function. Toxoplasma gondii rhoptry protein kinases and pseudokinases are involved in virulence and modulation of host cell signalling. The proteome of Plasmodium falciparum contains a family of putative kinases called FIKKs, some of which are exported to the host red blood cell and might play a role in erythrocyte remodelling. In this review we will discuss kinases known to be critical for host cell invasion, intracellular growth and egress, focusing on (i) calcium-dependent protein kinases and (ii) the secreted kinases that are unique to Toxoplasma (rhoptry protein kinases and pseudokinases) and Plasmodium (FIKKs).
    Full-text · Article · Dec 2011 · International journal for parasitology
  • Source
    • "These include transcription factors, RNA binding proteins, cell cycle regulators, chromatin remodeling associated proteins, histone modification enzymes as well as histones (Figure 3b, c, for complete list see Additional file 5 Sheet "Rank product score"). The most remarkable examples are strong down-regulation of genes coding for histone deacetylase 1 protein (HDAC1) (PFI1260c), recently proposed to play a major role in the transcriptional regulation [25], and CDK-activating kinase assembly factor (PFE0610c) whose paralogue was shown be associated with HDAC1 in P. falciparum [26]. Also, the artemisinin resistant parasites show a considerable up-regulation of the AP2 containing transcription factor (PF14_0079), bromo-domain containing protein (PFA0510w), putative histone acetyltransferase (hat; PF14_0350), zinc finger protein (PF14_0416), and the P. falciparum homologue of yeast histone chaperone Rttp106-like transcriptional regulator (PFE0870w). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Artemisinin resistance in Plasmodium falciparum malaria has emerged in Western Cambodia. This is a major threat to global plans to control and eliminate malaria as the artemisinins are a key component of antimalarial treatment throughout the world. To identify key features associated with the delayed parasite clearance phenotype, we employed DNA microarrays to profile the physiological gene expression pattern of the resistant isolates. In the ring and trophozoite stages, we observed reduced expression of many basic metabolic and cellular pathways which suggests a slower growth and maturation of these parasites during the first half of the asexual intraerythrocytic developmental cycle (IDC). In the schizont stage, there is an increased expression of essentially all functionalities associated with protein metabolism which indicates the prolonged and thus increased capacity of protein synthesis during the second half of the resistant parasite IDC. This modulation of the P. falciparum intraerythrocytic transcriptome may result from differential expression of regulatory proteins such as transcription factors or chromatin remodeling associated proteins. In addition, there is a unique and uniform copy number variation pattern in the Cambodian parasites which may represent an underlying genetic background that contributes to the resistance phenotype. The decreased metabolic activities in the ring stages are consistent with previous suggestions of higher resilience of the early developmental stages to artemisinin. Moreover, the increased capacity of protein synthesis and protein turnover in the schizont stage may contribute to artemisinin resistance by counteracting the protein damage caused by the oxidative stress and/or protein alkylation effect of this drug. This study reports the first global transcriptional survey of artemisinin resistant parasites and provides insight to the complexities of the molecular basis of pathogens with drug resistance phenotypes in vivo.
    Full-text · Article · Aug 2011 · BMC Genomics
  • Source
    • "This culminated in a kinome-wide systematic study identifying all P. berghei PKs with a role in transmission (Tewari et al., 2010). In parallel, a number of reverse genetics studies of P. falciparum kinases have been published (Abdi et al., 2010; Dorin-Semblat et al., 2007, 2008; Dvorin et al., 2010; Fennell et al., 2009; Halbert et al., 2010; Holland et al., 2009; McRobert et al., 2008; Merckx et al., 2008; Reininger et al., 2009; Taylor et al., 2010). Taken together, these sets of data allow the assignment of Abbreviation: HA, haemagglutinin. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Plasmodium falciparum kinome includes a family of four protein kinases (Pfnek-1 to -4) related to the NIMA (never-in-mitosis) family, members of which play important roles in mitosis and meiosis in eukaryotic cells. Only one of these, Pfnek-1, which we previously characterized at the biochemical level, is expressed in asexual parasites. The other three (Pfnek-2, -3 and -4) are expressed predominantly in gametocytes, and a role for nek-2 and nek-4 in meiosis has been documented. Here we show by reverse genetics that Pfnek-1 is required for completion of the asexual cycle in red blood cells and that its expression in gametocytes in detectable by immunofluorescence in male (but not in female) gametocytes, in contrast with Pfnek-2 and Pfnek-4. This indicates that the function of Pfnek-1 is non-redundant with those of the other members of the Pfnek family and identifies Pfnek-1 as a potential target for antimalarial chemotherapy. A medium-throughput screen of a small-molecule library provides proof of concept that recombinant Pfnek-1 can be used as a target in drug discovery.
    Full-text · Article · Jul 2011 · Microbiology
Show more