RNA



The MEP-1 zinc-finger protein acts with MOG DEAH box proteins to control gene expression via the fem-3 3′ untranslated region in Caenorhabditis elegans


MARCO  BELFIORE  a1, LAURA D.  MATHIES  a2 a3, PAOLO  PUGNALE  a1, GARY  MOULDER  a4, ROBERT  BARSTEAD  a4, JUDITH  KIMBLE  a2 a3 and ALESSANDRO  PUOTI  a1 c1
a1 Department of Zoology, University of Fribourg, Pérolles, CH-1700 Switzerland
a2 Department of Biochemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
a3 Howard Hughes Medical Institute, University of Wisconsin–Madison, Madison, Wisconsin 53706, USA
a4 Program in Molecular Biology, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA

Abstract

Cell fates in the Caenorhabditis elegans germline are regulated, at least in part, at the posttranscriptional level. For example, the switch from spermatogenesis to oogenesis in the hermaphrodite relies on posttranscriptional repression of the fem-3 mRNA via its 3′ untranslated region (UTR). Previous studies identified three DEAH box proteins, MOG-1, MOG-4, and MOG-5, that are critical for the fem-3 3′ UTR control. Here we describe MEP-1, a zinc-finger protein that binds specifically to each of these three MOG proteins and that is required for repression by the fem-3 3′ UTR in vivo. To investigate its in vivo function, we generated a mep-1 deletion mutant. The mep-1 null phenotype suggests a broad role for MEP-1 in C. elegans development, as it is associated with early larval arrest. In addition, mep-1 mutants can be defective in gonadogenesis and oocyte production when derived from a heterozygous mother. We suggest that MEP-1 acts together with the MOG proteins to repress fem-3 mRNA and that it also functions in other pathways to control development more broadly.

(Received November 21 2001)
(Revised January 3 2002)
(Accepted March 19 2002)


Key Words: posttranscriptional regulation; protein–protein interaction; protein–RNA interaction; sex determination; trans-acting factor.

Correspondence:
c1 Reprint requests to: Alessandro Puoti, Department of Zoology, University of Fribourg, Pérolles, CH-1700 Switzerland; e-mail: Alessandro.Puoti@unifr.ch.