A Regulatory RNA Motifs and Elements Finder
  Release 1.0, Jan 2006

Accession R0017
Feature Type RegRNA in 5'-UTR
Name Male specific lethal 3'UTR cis-acting element (MSL2-3UTR)
Regulatory Motif
uuuuuuu p1=10...20 uuuuuuu

p2=10...20 uuuuuuu p3=5...15

uuuuuuu length(p1+p2+p3)<40
Description Translational repression of msl-2 (male specific lethal) mRNA, which controls dosage compensation in Drosophila, is mediated by the female-specific RNA binding protein Sex-lethal (SXL). SXL binding to two sites, consisting respectively of U11 and U16 (or U17 in some isolates) located in the 5'UTR of the msl-2 mRNA, serves a dual function in inhibiting msl-2 expression in female flies: It enforces retention of a 5' UTR intron [splicing inhibition in the nucleus] and subsequently blocks translation in the cytoplasm. It has been observed that the cytoplasmic translational repression requires four additional SXL-binding sites (U7-U9) clustered in the 3'UTR. Experiments using a cell-free translation system from Drosophila embryos which recapitulates critical features of mRNA translation in eukaryotes such as cap and poly-A dependence, have shown that tight regulation of msl-2 translation requires cooperation between the SXL-binding sites in both the 5' and 3'UTRs but is not affected by poly-A tail as in numerous other developmentally regulated mRNAs.
References Gebauer F, Corona DF, Preiss T, Becker PB, and Hentze MW
Translational control of dosage compensation in Drosophila by Sex-lethal: cooperative silencing via the 5 and 3 UTRs of msl-2 mRNA is independent of the poly(A) tail.
EMBO J 1999; 18(21), 6146-54   PubMed 

Department of Biological Science and Technology, Institute of Bioinformatics, National Chiao Tung University, Taiwan
Contact with Dr. Hsien-Da Huang