Skip to main content
RNA logoLink to RNA
. 1995 May;1(3):293–303.

Caenorhabditis elegans embryos contain only one major species of Ro RNP.

D J Van Horn 1, D Eisenberg 1, C A O'Brien 1, S L Wolin 1
PMCID: PMC1369082  PMID: 7489501

Abstract

In virtually all vertebrate cells, Ro RNPs consist of the 60-kDa Ro autoantigen bound to one of several small cytoplasmic RNA molecules known as Y RNAs. Because the 60-kDa Ro autoantigen is also found complexed with defective precursors of 5S rRNA in Xenopus oocytes, we have proposed that this protein functions in a quality control, or discard pathway, for 5S RNA biosynthesis (O'Brien CA, Wolin SL, 1994, Genes & Dev 8:2891-2903). The role of the Y RNAs in this pathway is unknown. To begin a genetic analysis of Ro RNP function, we have characterized these particles in the nematode Caenorhabditis elegans. The C. elegans Ro protein is 12 kDa larger than the vertebrate protein; the larger size is due in part to an N-terminal extension and to two insertions in the RNA recognition motif. In contrast to all previously described vertebrate species, the Ro protein appears bound to a single Y RNA in C. elegans. Similar to vertebrate Y RNAs, the C. elegans Y RNA can be folded to form a pyrimidine-rich internal loop and a long stem in which the 5' and 3' ends are base paired. Within the stem is a conserved bulged helix that is proposed to be the binding site of the Ro protein. Interestingly, although the human protein can bind the nematode Y RNA, the C. elegans protein does not bind human Y RNAs. This is the first description of Ro RNPs in an invertebrate species.

Full Text

The Full Text of this article is available as a PDF (7.4 MB).


Articles from RNA are provided here courtesy of The RNA Society

RESOURCES