Premium
Human ribosomes from cells with reduced dyskerin levels are intrinsically altered in translation
Author(s) -
Penzo Marianna,
Rocchi Laura,
Brugiere Sabine,
Carnicelli Domenica,
Onofrillo Carmine,
Couté Yohann,
Brigotti Maurizio,
Montanaro Lorenzo
Publication year - 2015
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fj.15-270991
Subject(s) - ribosome , pseudouridine , ribosomal rna , translation (biology) , biology , dyskeratosis congenita , rna , protein biosynthesis , microbiology and biotechnology , internal ribosome entry site , small nucleolar rna , ribosomal protein , biochemistry , chemistry , messenger rna , transfer rna , non coding rna , gene , telomerase
Dyskerin is a pseudouridine (ψ)synthaseinvolved in fundamental cellular processes including uridine modification in rRNA and small nuclear RNA and telomere stabilization. Dyskerin functions are altered in X‐linked dyskeratosis congenita (X‐DC) and cancer. Dyskerin's role in rRNA pseudouridylation has been suggested to underlie the alterations in mRNA translation described in cells lacking dyskerin function, although relevant direct evidences are currently lacking. Our purpose was to establish definitely whether defective dyskerin function might determine an intrinsic ribosomal defect leading to an altered synthetic activity. Therefore, ribosomes from dyskerin‐depleted human cells were purified and 1) added to a controlled reticulocyte cell‐free system devoid of ribosomes to study mRNA translation; 2) analyzed for protein contamination and composition by mass spectrometry, 3) analyzed for global pseudouridylation levels. Ribosomes purified from dyskerin‐depleted cells showed altered translational fidelity and internal ribosome entry site (IRES)‐mediated translation. These ribosomes displayed reduced uridine modification, whereas they were not different in terms of protein contamination or ribosomal protein composition with respect to ribosomes from matched control cells with full dyskerin activity. In conclusion, lack of dyskerin function in human cells induces a defect in rRNA uridine modification, which is sufficient to alter ribosome activity.—Penzo, M., Rocchi, L., Brugiere, S., Carnicelli, D., Onofrillo, C., Couté, Y., Brigotti, M., Montanaro, L. Human ribosomes from cells with reduced dyskerin levels are intrinsically altered in translation. FASEB J. 29, 3472‐3482 (2015). www.fasebj.org