Lipoxygenase mRNA silencing in erythroid differentiation: The 3'UTR regulatory complex controls 60S ribosomal subunit joining.
15-lipoxygenase (LOX) expression is translationally silenced in early erythroid precursor cells by a specific mRNA-protein complex formed between the differentiation control element in the 3' untranslated region (UTR) and hnRNPs K and E1. The 3'UTR regulatory complex prevents translation initiation by an unknown mechanism. We demonstrate that the 40S ribosomal subunit can be recruited and scan to the translation initiation codon even when the silencing complex is bound to the 3'UTR. However, the joining of the 60S ribosomal subunit at the AUG codon to form a translation competent 80S ribosome is inhibited, unless initiation is mediated by the IGR-IRES of the cricket paralysis virus. These findings identify the critical step at which LOX mRNA translation is controlled and reveal that 60S subunit joining can be specifically regulated.
Ostareck
D H
DH
Gene Expression Programme, European Molecular Biology Laboratory, Meyerhofstrasse 1, D-69117, Heidelberg, Germany.
Ostareck-Lederer
A
A
Shatsky
I N
IN
Hentze
M W
MW
D020413:3' Untranslated Regions / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001093:Arachidonate 15-Lipoxygenase / Q000235:genetics* / Q000378:metabolism; D002213:Capsid / Q000235:genetics / Q000378:metabolism; D036022:Capsid Proteins; D002474:Cell-Free System; D003001:Cloning, Molecular; D020868:Gene Silencing; D017930:Genes, Reporter; D066298:In Vitro Techniques; D046911:Macromolecular Substances; D008954:Models, Biological; D008957:Models, Genetic; D014176:Protein Biosynthesis; D012332:RNA, Heterogeneous Nuclear / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012156:Reticulocytes / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*
D020413:3' Untranslated Regions; D036022:Capsid Proteins; D046911:Macromolecular Substances; D012332:RNA, Heterogeneous Nuclear; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012261:Ribonucleoproteins; D012269:Ribosomal Proteins; C120684:capsid protein, Cricket paralysis virus; D001093:Arachidonate 15-Lipoxygenase