title: Schistosoma mansoni Polo-like kinase 1: A mitotic kinase with key functions in parasite reproduction.
abstract: Polo-like kinases (Plks) are conserved regulators of mitosis. In mammals, Plk1 is over-expressed in a wide range of tumour cells and constitutes a valuable target for anti-cancer therapy. This work presents the characterisation of the Plk1 homologue (SmPlk1) of Schistosoma mansoni, a trematode responsible for schistosomiasis, one of the most important parasitic diseases, second only to malaria. The intense levels of disease transmission and the severity of pathologies are the consequences of the exceptional reproductive activity of schistosomes, in which Plks may play a decisive role. Structural and functional analyses of SmPlk1 have demonstrated its homology with other Plk1 members and its conserved function in mitotic processes. Activation of SmPlk1 was shown to be dependent on phosphorylation of its conserved threonine residue (T(182)) and the ability of active SmPlk1 to induce mitosis was demonstrated in the Xenopus oocyte model. SmPlk1 transcripts were detected abundantly in parasite stages containing a high amount of germinal cells. A potential role of SmPlk1 in mitosis and/or meiosis in schistosomes was supported by the in situ detection of SmPlk1 transcripts in female vitelline cells and oocytes as well as in male spermatocytes. Several Plk inhibitors were shown to inhibit SmPlk1 activity in Xenopus oocytes, and BI 2536 (the first-in-class prototype Plk1 inhibitor) induced in vitro dramatic alterations in schistosome gonads, which affected oogenesis and spermatogenesis. These results indicate a major role for SmPlk1 in parasite reproduction and suggest its importance as a potential new target against schistosomiasis.
authors.affiliation: CIIL - Center for Infection and Immunity of Lille Inserm U1019 - CNRS UMR 8204, University Lille Nord de France, Institut Pasteur de Lille, 59019 Lille Cedex, France.
authors.forename: Thavy
authors.initials: T
authors.lastname: Long
authors.forename: Katia
authors.initials: K
authors.lastname: Cailliau
authors.forename: Svenja
authors.initials: S
authors.lastname: Beckmann
authors.forename: Edith
authors.initials: E
authors.lastname: Browaeys
authors.forename: Jacques
authors.initials: J
authors.lastname: Trolet
authors.forename: Christoph G
authors.initials: CG
authors.lastname: Grevelding
authors.forename: Colette
authors.initials: C
authors.lastname: Dissous
mesh_terms: D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D017124:Conserved Sequence; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D005260:Female; D015801:Helminth Proteins / Q000235:genetics / Q000502:physiology*; D008297:Male; D008938:Mitosis; D008969:Molecular Sequence Data; D009865:Oocytes; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D012098:Reproduction; D012550:Schistosoma mansoni / Q000201:enzymology* / Q000502:physiology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013090:Spermatocytes; D013912:Threonine / Q000378:metabolism; D014981:Xenopus; D000097869:Polo-Like Kinase 1
chemical_list: D018797:Cell Cycle Proteins; D018509:DNA, Helminth; D015801:Helminth Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D013912:Threonine; D000097869:Polo-Like Kinase 1