Zaineb Fourati, Bijoyita Roy, Claudia Millan, Pierre-Damien Coureux, Stéphanie Kervestin, Herman van Tilbeurgh, Feng He, Isabel Usón, Allan Jacobson, Marc Graille
Upf1, Upf2, and Upf3 are the principal regulators of nonsense-mediated mRNA decay (NMD), a cytoplasmic surveillance pathway that accelerates the degradation of mRNAs undergoing premature translation termination. These three proteins interact with each other, the ribosome, the translation termination machinery, and multiple mRNA decay factors, but the precise mechanism allowing the selective detection and degradation of nonsense-containing transcripts remains elusive. Here, we have determined the crystal structure of the N-terminal mIF4G domain from Saccharomyces cerevisiae Upf2 and identified a highly conserved region in this domain that is essential for NMD and independent of Upf2's binding sites for Upf1 and Upf3...
November 11, 2014: Journal of Molecular Biology