title: SmSak, the second Polo-like kinase of the helminth parasite Schistosoma mansoni: conserved and unexpected roles in meiosis.
abstract: Polo-like kinases (Plks) are a family of conserved regulators of a variety of events throughout the cell cycle, expanded from one Plk in yeast to five Plks in mammals (Plk1-5). Plk1 is the best characterized member of the Plk family, homolog to the founding member Polo of Drosophila, and plays a major role in cell cycle progression by triggering G2/M transition. Plk4/Sak (for Snk (Serum-inducible kinase) akin kinase) is a unique member of the family, structurally distinct from other Plk members, with essential functions in centriole duplication. The genome of the trematode parasite Schistosoma mansoni contains only two Plk genes encoding SmPlk1 and SmSak. SmPlk1 has been shown already to be required for gametogenesis and parasite reproduction. In this work, in situ hybridization indicated that the structurally conserved Plk4 protein, SmSak, was largely expressed in schistosome female ovary and vitellarium. Expression of SmSak in Xenopus oocytes confirmed its Plk4 conserved function in centriole amplification. Moreover, analysis of the function of SmSak in meiosis progression of G2-blocked Xenopus oocytes indicated that, in contrast to SmPlk1, SmSak cannot induce G2/M transition in the absence of endogenous Plk1 (Plx1). Unexpectedly, meiosis progression was spontaneously observed in Plx1-depleted oocytes co-expressing SmSak and SmPlk1. Molecular interaction between SmSak and SmPlk1 was confirmed by co-immunoprecipitation of both proteins. These data indicate that Plk1 and Plk4 proteins have the potential to interact and cross-activate in cells, thus attributing for the first time a potential role of Plk4 proteins in meiosis/mitosis entry. This unexpected role of SmSak in meiosis could be relevant to further consider the function of this novel Plk in schistosome reproduction.
authors: Center for Infection and Immunity of Lille, Inserm U1019, CNRS-UMR 8204, University Lille Nord de France, Institut Pasteur de Lille, Lille, France.
authors: Thavy
authors: T
authors: Long
authors: Mathieu
authors: M
authors: Vanderstraete
authors: Katia
authors: K
authors: Cailliau
authors: Marion
authors: M
authors: Morel
authors: Arlette
authors: A
authors: Lescuyer
authors: Nadege
authors: N
authors: Gouignard
authors: Christoph G
authors: CG
authors: Grevelding
authors: Edith
authors: E
authors: Browaeys
authors: Colette
authors: C
authors: Dissous
mesh_terms: D000818:Animals; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002502:Centrioles / Q000378:metabolism; D003001:Cloning, Molecular; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008018:Life Cycle Stages; D008297:Male; D008540:Meiosis; D009865:Oocytes / Q000378:metabolism; D010271:Parasites / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012550:Schistosoma mansoni / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D014981:Xenopus; D000097869:Polo-Like Kinase 1
chemical_list: D018797:Cell Cycle Proteins; D015801:Helminth Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D000097869:Polo-Like Kinase 1