title: Plasmodium falciparum Werner homologue is a nuclear protein and its biochemical activities reside in the N-terminal region.
abstract: RecQ helicases, also addressed as a gatekeeper of genome, are an inevitable family of genome scrutiny proteins conserved from prokaryotes to eukaryotes and play a vital role in DNA metabolism. The deficiencies of three RecQ proteins out of five are involved in genetic abnormalities like Bloom syndrome (BS), Werner syndrome (WS), and Rothmund-Thomson syndrome (RTS). It is noteworthy that Plasmodium falciparum contains only two members of the RecQ family as opposed to five members present in the host Homo sapiens. In the present study, we report the biochemical characterization of the homologue of Werner (Wrn) helicase from P. falciparum 3D7 strain. Although there are significant sequence conservations between Wrn helicases of both H. sapiens and P. falciparum as well as among all the other Plasmodium species, they contain some peculiar differences also. In silico studies reveal that PfWrn is evolutionarily close to the bacterial RecQ protein. The N-terminal fragment (PfWrnN) contains all the helicase motifs along with all the functional domains and the predicted structure resembles with the human RecQ1 protein, whereas the C-terminal fragment (PfWrnC) contains no significant domain. Biochemical characterization further revealed that purified recombinant PfWrnN shows ATPase and DNA helicase activity in 3' to 5' direction, but PfWrnC lacks the ATPase and helicase activities. Immunofluorescence study shows that PfWrn is expressed in all the stages of intraerythrocytic development of the P. falciparum 3D7 strain and localizes distinctly in the nucleus. This study can be used for further characterization of RecQ helicases that will aid in understanding the physiological significance of these helicases in the malaria parasite.
authors.affiliation: Malaria Group, International Centre for Genetic Engineering and Biotechnology, P. O. Box 10504, Aruna Asaf Ali Marg, New Delhi, 110067, India.
authors.forename: Farhana
authors.initials: F
authors.lastname: Rahman
authors.affiliation: Malaria Group, International Centre for Genetic Engineering and Biotechnology, P. O. Box 10504, Aruna Asaf Ali Marg, New Delhi, 110067, India.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Tarique
authors.affiliation: Malaria Group, International Centre for Genetic Engineering and Biotechnology, P. O. Box 10504, Aruna Asaf Ali Marg, New Delhi, 110067, India.
authors.forename: Moaz
authors.initials: M
authors.lastname: Ahmad
authors.affiliation: Malaria Group, International Centre for Genetic Engineering and Biotechnology, P. O. Box 10504, Aruna Asaf Ali Marg, New Delhi, 110067, India. renu@icgeb.res.in.
authors.forename: Renu
authors.initials: R
authors.lastname: Tuteja
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D003198:Computer Simulation; D004265:DNA Helicases / Q000378:metabolism; D004912:Erythrocytes / Q000469:parasitology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D009711:Nucleotides / Q000378:metabolism; D010963:Plasmodium falciparum / Q000378:metabolism*; D011485:Protein Binding; D015800:Protozoan Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D040681:Structural Homology, Protein; D013329:Structure-Activity Relationship
chemical_list: D009687:Nuclear Proteins; D009711:Nucleotides; D015800:Protozoan Proteins; D000251:Adenosine Triphosphatases; D004265:DNA Helicases
keywords: BLM; DNA helicase; Malaria parasite; Nucleic acid unwinding; RecQ; WRN
references.citation: Nat Rev Cancer. 2003 Mar;3(3):169-78
references.pmid: 12612652
references.citation: Nat Genet. 2013 Jun;45(6):648-55
references.pmid: 23624527
references.citation: Cell Cycle. 2010 Jan 1;9(1):104-20
references.pmid: 20016272
references.citation: Mol Gen Genet. 1984;195(3):474-80
references.pmid: 6381965
references.citation: Mol Biochem Parasitol. 2005 Dec;144(2):133-41
references.pmid: 16165232
references.citation: Biochim Biophys Acta. 2013 Dec;1834(12):2795-811
references.pmid: 24161468
references.citation: J Biol Chem. 1998 Dec 18;273(51):34139-44
references.pmid: 9852073
references.citation: FEBS J. 2007 Sep;274(18):4699-704
references.pmid: 17824956
references.citation: Lancet. 2014 Feb 22;383(9918):723-35
references.pmid: 23953767
references.citation: Science. 1996 Apr 12;272(5259):258-62
references.pmid: 8602509
references.citation: Nucleic Acids Res. 2006;34(15):4168-80
references.pmid: 16936318
references.citation: Eur J Biochem. 2004 May;271(10):1849-63
references.pmid: 15128295
references.citation: Microbiol Rev. 1994 Sep;58(3):401-65
references.pmid: 7968921
references.citation: Nucleic Acids Res. 1998 Jun 15;26(12 ):2879-85
references.pmid: 9611231
references.citation: Medicine (Baltimore). 1993 Nov;72(6):393-406
references.pmid: 8231788
references.citation: Parasitol Today. 2000 Apr;16(4):146-53
references.pmid: 10725901
references.citation: Mol Cell Biol. 1997 Dec;17(12):6868-75
references.pmid: 9372918
references.citation: IUBMB Life. 2010 Jul;62(7):548-53
references.pmid: 20552646
references.citation: Mol Cell Biol. 1994 Dec;14(12):8391-8
references.pmid: 7969174
references.citation: Mol Biochem Parasitol. 2014 Jun;195(1):34-42
references.pmid: 24914817
references.citation: DNA Repair (Amst). 2014 Oct;22:137-46
references.pmid: 25198671
references.citation: PLoS One. 2012;7(11):e49385
references.pmid: 23185322
references.citation: Cell Cycle. 2013 Oct 1;12(19):3125-6
references.pmid: 24013420
references.citation: Mol Biochem Parasitol. 2014 Aug;196(1):41-4
references.pmid: 25111966
references.citation: Malar J. 2014 May 25;13:189
references.pmid: 24886347
references.citation: Biochim Biophys Acta. 2014 Dec;1842(12 Pt A):2387-94
references.pmid: 25257404
references.citation: Exp Cell Res. 1998 Aug 1;242(2):487-94
references.pmid: 9683536
references.citation: Eur J Biochem. 2004 May;271(10):1835-48
references.pmid: 15128294
references.citation: J Bacteriol. 2014 Dec;196(24):4216-28
references.pmid: 25246477
references.citation: Annu Rev Biochem. 2014;83:519-52
references.pmid: 24606147