RNA recognition by the embryonic cell fate determinant and germline totipotency factor MEX-3
- Department of Biochemistry and Molecular Pharmacology, 364 Plantation Street, LRB-906, University of Massachusetts Medical School, Worcester, MA 01605
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Edited by Jennifer A. Doudna, University of California, Berkeley, CA, and approved October 1, 2009 (received for review July 15, 2009)
Abstract
Totipotent stem cells have the potential to differentiate into every cell type. Renewal of totipotent stem cells in the germline and cellular differentiation during early embryogenesis rely upon posttranscriptional regulatory mechanisms. The Caenorhabditis elegans RNA binding protein, MEX-3, plays a key role in both processes. MEX-3 is a maternally-supplied factor that controls the RNA metabolism of transcripts encoding critical cell fate determinants. However, the nucleotide sequence specificity and requirements of MEX-3 mRNA recognition remain unclear. Only a few candidate regulatory targets have been identified, and the full extent of the network of MEX-3 targets is not known. Here, we define the consensus sequence required for MEX-3 RNA recognition and demonstrate that this element is required for MEX-3 dependent regulation of gene expression in live worms. Based on this work, we identify several candidate MEX-3 targets that help explain its dual role in regulating germline stem cell totipotency and embryonic cell fate specification.
Footnotes
- 1To whom correspondence should be addressed. E-mail: sean.ryder{at}umassmed.edu
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Author contributions: J.M.P. and S.P.R. designed research; J.M.P. and K.I.E. performed research; J.M.P. and B.M.F. contributed new reagents/analytic tools; J.M.P., B.M.F., and S.P.R. analyzed data; and J.M.P. and S.P.R. wrote the paper.
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The authors declare no conflict of interest.
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This article is a PNAS Direct Submission.
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This article contains supporting information online at www.pnas.org/cgi/content/full/0907916106/DCSupplemental.
