title: NANOS1 and PUMILIO2 bind microRNA biogenesis factor GEMIN3, within chromatoid body in human germ cells.
abstract: Nanos and pumilio bind each other to regulate translation of specific mRNAs in germ cells of model organisms, such as D. melanogaster or C. elegans. Recently described human homologues NANOS1 and PUMILIO2 form a complex similar to their ancestors. This study was aimed to identify the proteins interacting with NANOS1-PUMILIO2 complex in the human spermatogenic cells. Here, using the yeast two-hybrid system we found that NANOS1 and PUMILIO2 proteins interact with RNA DEAD-box helicase GEMIN3, a microRNA biogenesis factor. Moreover, GEMIN3 coimmunoprecipitates with NANOS1 and PUMILIO2 in transfected mammalian cells. By double immunofluorescence staining, we observed that complexes built of NANOS1, PUMILIO2 and GEMIN3 are located within cytoplasmic region of germ cells. These proteins condense to form a compact aggregate in the round spermatids of the human and mouse germ cells. This aggregate was reminiscent of the chromatoid body (CB), a perinuclear structure present in the mammalian male germ line. This structure is considered evolutionary remnant of germ plasm, a hallmark structure of germ cells in lower metazoan. Using a CB marker VASA protein, we demonstrated that CBs are present in the human round spermatids, as they are in the mouse. Moreover, NANOS1, PUMILIO2 and GEMIN3 colocalize with VASA protein. We demonstrated for the first time that a mammalian Nanos-Pumilio complex functions within CB, a center of RNA storing and processing, involving microRNAs. NANOS1-PUMILIO2 complex, together with GEMIN3 and small noncoding RNAs, possibly regulate mRNA translation within CB of the human germ cells.
authors.affiliation: Institute of Human Genetics Polish Academy of Sciences, Poznan, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Ginter-Matuszewska
authors.forename: Kamila
authors.initials: K
authors.lastname: Kusz
authors.forename: Anna
authors.initials: A
authors.lastname: Spik
authors.forename: Dominika
authors.initials: D
authors.lastname: Grzeszkowiak
authors.forename: Alina
authors.initials: A
authors.lastname: Rembiszewska
authors.forename: Jolanta
authors.initials: J
authors.lastname: Kupryjanczyk
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Jaruzelska
mesh_terms: D000818:Animals; D001665:Binding Sites; D002842:Chromatids / Q000378:metabolism*; D055541:DEAD Box Protein 20 / Q000378:metabolism*; D053487:DEAD-box RNA Helicases / Q000378:metabolism; D005854:Germ Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D008297:Male; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism*; D012671:Seminiferous Tubules / Q000378:metabolism
chemical_list: D035683:MicroRNAs; C515170:NANOS1 protein, human; C471243:PUM2 protein, human; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C498288:DDX4 protein, human; D055541:DEAD Box Protein 20; D053487:DEAD-box RNA Helicases