XB-ART-39482Mol Cell Biol July 1, 2009; 29 (13): 3791-802.
Spatially restricted translation of the xCR1 mRNA in Xenopus embryos.
The xCR1 protein is a maternal determinant and cofactor for nodal signaling in vertebrate embryos. The xCR1 protein accumulates specifically in the animal cells of Xenopus embryos, but maternal xCR1 mRNA is distributed equally throughout all embryonic cells. Here, we show that vegetal cell-specific translational repression of xCR1 mRNA contributes to this spatially restricted accumulation of the xCR1 protein in Xenopus embryos. xCR1 mRNA was associated with polyribosomes in animal cells but not vegetal cells. A 351-nucleotide region of xCR1 mRNA''s 3'' untranslated region was sufficient to confer a spatially restricted pattern of translation to a luciferase reporter mRNA by repressing translation in vegetal cells. Repression depended upon the mRNA''s 5'' cap but not its 3'' poly(A) tail. Furthermore, the region of xCR1 mRNA sufficient to confer vegetal cell-specific repression contained both Pumilio binding elements (PBEs) and binding sites for the CUG-BP1 protein. The PBEs and the CUG-BP1 sites were necessary but not sufficient for translation repression. Our studies of xCR1 mRNA document the first example of spatially regulated translation in controlling the asymmetric distribution of a maternal determinant in vertebrates.
PubMed ID: 19364820
PMC ID: PMC2698763
Article link: Mol Cell Biol
Genes referenced: celf1 nodal nodal1 pum1 tdgf1.3 xcr1
References [+] :
Cao, Dissolution of the maskin-eIF4E complex by cytoplasmic polyadenylation and poly(A)-binding protein controls cyclin B1 mRNA translation and oocyte maturation. 2002, Pubmed, Xenbase