A novel tetratricopeptide repeat (TPR) containing PP5 serine/threonine protein phosphatase in the malaria parasite, Plasmodium falciparum

被引:39
作者
Dobson S. [1 ]
Kar B. [1 ]
Kumar R. [1 ]
Adams B. [1 ]
Barik S. [1 ]
机构
[1] Dept. of Biochem. and Molec. Biology, University of South Alabama, College of Medicine, Mobile, AL 36688-0002
关键词
Okadaic Acid; Catalytic Core; Tetratricopeptide Repeat; Nickel Chelation Affinity Chromatography; Asexual Erythrocytic Stage;
D O I
10.1186/1471-2180-1-31
中图分类号
学科分类号
摘要
Background: The malarial parasite, Plasmodium falciparum (Pf), is responsible for nearly 2 million deaths worldwide. However, the mechanisms of cellular signaling in the parasite remain largely unknown. Recent discovery of a few protein kinases and phosphatases point to a thriving reversible phosphorylation system in the parasite, although their function and regulation need to be determined. Results: We provide biochemical and sequence evidence for a protein serine/threonine phosphatase type PP5 in Plasmodium falciparum, and named it PfPP5. The 594-amino acid polypeptide was encoded by a 1785 nucleotide long intronless gene in the parasite. The recombinant protein, expressed in bacteria, was indistinguishable from native PfPP5. Sequencing comparison indicated that the extra-long N-terminus of PfPP5 outside the catalytic core contained four tetratricopeptide repeats (TPRs), compared to three such repeats in other PP5 phosphatases. The PfPP5 N-terminus was required for stimulation of the phosphatase activity by polyunsaturated fatty acids. Co-immunoprecipitation demonstrated an interaction between native PfPP5 and Pf heat shock protein 90 (hsp90). PfPP5 was expressed in all the asexual erythrocytic stages of the parasite, and was moderately sensitive to okadaic acid. Conclusions: This is the first example of a TPR-domain protein in the Apicomplexa family of parasites. Since TPR domains play important roles in protein-protein interaction, especially relevant to the regulation of PP5 phosphatases, PfPP5 is destined to have a definitive role in parasitic growth and signaling pathways. This is exemplified by the interaction between PfPP5 and the cognate chaperone hsp90.
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页码:1 / 10
页数:9
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共 40 条
[21]  
Sinclair C., Borchers C., Parker C., Tomer K., Charbonneau H., Rossie S., The tetratricopeptide repeat domain and a C-terminal region control the activity of Ser/Thr protein phosphatase 5, J Biol Chem, 274, pp. 23666-23672, (1999)
[22]  
Barton G.J., Cohen P.T., Barford D., Conservation analysis and structure prediction of the protein serine/threonine phosphatases. Sequence similarity with diadenosine tetraphosphatase from Escherichia coli suggests homology to the protein phosphatases, Eur J Biochem, 220, pp. 225-227, (1994)
[23]  
Bank S., Expression and biochemical properties of a protein serine/threonine phosphatase encoded by bacteriophage lambda, Proc Natl Acad Sci USA, 90, pp. 10633-10637, (1993)
[24]  
Zhuo S., Clemens J.C., Stone R.L., Dixon J.E., Mutational analysis of a Ser/Thr phosphatase. Identification of residues important in phosphoesterase substrate binding and catalysis, J Biol Chem, 269, pp. 26234-26238, (1994)
[25]  
Ansai T., Dupuy L.C., Bank S., Interactions between a minimal protein serine/threonine phosphatase and its phosphopeptide substrate sequence, J Biol Chem, 271, pp. 24401-24407, (1996)
[26]  
Zhang L., Lee E.Y., Mutational analysis of substrate recognition by protein phosphatase 1, Biochemistry, 36, pp. 8209-8214, (1997)
[27]  
Connor J.H., Quan H.Q., Ramaswamy N.T., Zhang L., Bank S., Zheng J., Cannon J.P., Lee E.Y.C., Shenolikar S., Inhibitor-1 interaction domain that mediates the inhibition of protein phosphatase-1, J Biol Chem, 273, pp. 27716-27724, (1998)
[28]  
Connor J.H., Kleeman T., Bank S., Honkanen R.E., Shenolikar S., Importance of the β12-β13 loop in protein phosphatase-1 catalytic subunit for inhibition by toxins and mammalian protein inhibitors, J Biol Chem, 274, pp. 22366-22372, (1999)
[29]  
Goldberg J., Huang H.B., Kwon Y.G., Greengard P., Nairn A.C., Kuriyan J., Three-dimensional structure of the catalytic subunit of protein serine/threonine phosphatase-1, Nature, 376, pp. 745-753, (1995)
[30]  
Chaudhuri M., Cloning and characterization of a novel serine/threonine protein phosphatase type 5 from Trypanosoma brucei, Gene, 266, pp. 1-13, (2001)