Article
- The EMBO Journal (2006) 25, 1263 - 1272
- doi:10.1038/sj.emboj.7601022
Published online: 2 March 2006
Subject Categories:
Drosophila Sex-lethal protein mediates polyadenylation switching in the female germline
Bharat Gawandea, Mark D Robidaa, Andrew Rahn and Ravinder Singh
- Department of Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO, USA
Correspondence to:
Ravinder Singh, Department of Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA. Tel.: +1 303 492 8886; Fax: +1 303 492 7744; E-mail: rsingh@colorado.edu
aThese authors contributed equally to this work
Received 22 August 2005; Accepted 2 February 2006
Abstract
The Drosophila master sex-switch protein Sex-lethal (SXL) regulates the splicing and/or translation of three known targets to mediate somatic sexual differentiation. Genetic studies suggest that additional target(s) of SXL exist, particularly in the female germline. Surprisingly, our detailed molecular characterization of a new potential target of SXL, enhancer of rudimentary (e(r)), reveals that SXL regulates e(r) by a novel mechanism—polyadenylation switching—specifically in the female germline. SXL binds to multiple SXL-binding sites, which include the GU-rich poly(A) enhancer, and competes for the binding of CstF64 in vitro. The SXL-binding sites are able to confer sex-specific poly(A) switching onto an otherwise nonresponsive polyadenylation signal in vivo. The sex-specific poly(A) switching of e(r) provides a means for translational regulation in germ cells. We present a model for the SXL-dependent poly(A) site choice in the female germline.
Keywords:
- e(r),
- GU-rich element,
- RNA-binding proteins,
- polyadenylation,
- translation
