Analysis of RNA associated with P granules in germ cells of C. elegans adults.
P granules are cytoplasmic structures of unknown function that are associated with germ nuclei in the C. elegans gonad, and are localized exclusively to germ cells, or germ cell precursors, throughout the life cycle. All the known protein components of P granules contain putative RNA-binding motifs, suggesting that RNA is involved in either the structure or function of the granules. However, no specific mRNAs have been identified within P granules in the gonad. We show here that P granules normally contain a low level of RNA, and describe conditions that increase this level. We present evidence that several, diverse mRNAs, including pos-1, mex-1, par-3, skn-1, nos-2 and gld-1 mRNA, are present at least transiently within P granules. In contrast, actin and tubulin mRNA and rRNA are either not present in P granules, or are present at relatively low levels. We show that pgl-1 and the glh (Vasa-related) gene family, which encode protein components of P granules, do not appear essential for RNA to concentrate in P granules; these proteins may instead function in events that are a prerequisite for RNAs to be transported efficiently from the nuclear surface.
Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109; Department of Zoology, University of Washington, Seattle, Washington 98195; and Howard Hughes Medical Institute, Seattle, Washington 98109, USA.
J A
JA
Schisa
J N
JN
Pitt
J R
JR
Priess
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics; D003594:Cytoplasmic Granules / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005854:Germ Cells; D006066:Gonads / Q000378:metabolism; D015801:Helminth Proteins / Q000235:genetics*; D016296:Mutagenesis; D017346:Protein Serine-Threonine Kinases; D018510:RNA, Helminth / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics; D014157:Transcription Factors
D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C115306:FEM-1 protein, C elegans; C094448:GLD-1 protein, C elegans; D015801:Helminth Proteins; C114543:PGL-1 protein, C elegans; C117258:POS-1 protein, C elegans; D018510:RNA, Helminth; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D014157:Transcription Factors; C104694:mex-1 protein, C elegans; C400703:nos-2 protein, C elegans; C073702:skn-1 protein, C elegans; C097238:PAR-3 protein, C elegans; D017346:Protein Serine-Threonine Kinases