title: The CCR4 deadenylase acts with Nanos and Pumilio in the fine-tuning of Mei-P26 expression to promote germline stem cell self-renewal.
abstract: Translational regulation plays an essential role in Drosophila ovarian germline stem cell (GSC) biology. GSC self-renewal requires two translational repressors, Nanos (Nos) and Pumilio (Pum), which repress the expression of differentiation factors in the stem cells. The molecular mechanisms underlying this translational repression remain unknown. Here, we show that the CCR4 deadenylase is required for GSC self-renewal and that Nos and Pum act through its recruitment onto specific mRNAs. We identify mei-P26 mRNA as a direct and major target of Nos/Pum/CCR4 translational repression in the GSCs. mei-P26 encodes a protein of the Trim-NHL tumor suppressor family that has conserved functions in stem cell lineages. We show that fine-tuning Mei-P26 expression by CCR4 plays a key role in GSC self-renewal. These results identify the molecular mechanism of Nos/Pum function in GSC self-renewal and reveal the role of CCR4-NOT-mediated deadenylation in regulating the balance between GSC self-renewal and differentiation.
authors.affiliation: mRNA Regulation and Development, Institute of Human Genetics, CNRS UPR1142, 141 Rue de la Cardonille, 34396 Montpellier Cedex 5, France.
authors.forename: Willy
authors.initials: W
authors.lastname: Joly
authors.forename: Aymeric
authors.initials: A
authors.lastname: Chartier
authors.forename: Patricia
authors.initials: P
authors.lastname: Rojas-Rios
authors.forename: Isabelle
authors.initials: I
authors.lastname: Busseau
authors.forename: Martine
authors.initials: M
authors.lastname: Simonelig
mesh_terms: D000818:Animals; D019070:Cell Lineage; D049109:Cell Proliferation; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D009866:Oogenesis; D010063:Ovum / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012260:Ribonucleases / Q000235:genetics / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism* / Q000502:physiology
chemical_list: D029721:Drosophila Proteins; C530643:Mei-P26 protein, Drosophila; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C074333:pum protein, Drosophila; C070574:nos protein, Drosophila; C501437:CCR4 protein, Drosophila; D012260:Ribonucleases