title: Sm proteins specify germ cell fate by facilitating oskar mRNA localization.
abstract: Sm and Sm-like proteins are RNA-binding factors found in all three domains of life. Eukaryotic Sm proteins play essential roles in pre-mRNA splicing, forming the cores of spliceosomal small nuclear ribonucleoproteins (snRNPs). Recently, Sm proteins have been implicated in the specification of germ cells. However, a mechanistic understanding of their involvement in germline specification is lacking and a germline-specific RNA target has not been identified. We demonstrate that Drosophila SmB and SmD3 are specific components of the oskar messenger ribonucleoprotein (mRNP), proper localization of which is required for establishing germline fate and embryonic patterning. Importantly, oskar mRNA is delocalized in females harboring a hypomorphic mutation in SmD3, and embryos from mutant mothers are defective in germline specification. We conclude that Sm proteins function to establish the germline in Drosophila, at least in part by mediating oskar mRNA localization.
authors.affiliation: Departments of Biology and Genetics, Program in Molecular Biology and Biotechnology, University of North Carolina, Chapel Hill, NC 27599-3280, USA. ggonsalvez@mcg.edu
authors.forename: Graydon B
authors.initials: GB
authors.lastname: Gonsalvez
authors.forename: T K
authors.initials: TK
authors.lastname: Rajendra
authors.forename: Ying
authors.initials: Y
authors.lastname: Wen
authors.forename: Kavita
authors.initials: K
authors.lastname: Praveen
authors.forename: A Gregory
authors.initials: AG
authors.lastname: Matera
mesh_terms: D000818:Animals; D004330:Drosophila / Q000235:genetics / Q000378:metabolism; D056890:Eukaryota; D005260:Female; D005854:Germ Cells / Q000378:metabolism; D009154:Mutation; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear / Q000235:genetics / Q000378:metabolism*; D017381:Spliceosomes / Q000235:genetics / Q000378:metabolism
chemical_list: D011506:Proteins; D012322:RNA Precursors; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; C026452:messenger ribonucleoprotein