CDKN2A/p16INK4a is an essential tumor suppressor gene that controls cell cycle progression and replicative senescence. It is also the main melanoma susceptibility gene. Here we report that p16INK4a 5'UTR mRNA acts as a cellular Internal Ribosome Entry Site (IRES). The potential for p16INK4a 5'UTR to drive cap-independent translation was evaluated by dual-luciferase assays using bicistronic and monocistronic vectors. Results of reporters' relative activities coupled to control analyses for actual bicistronic mRNA transcription, indicated that the wild type p16INK4a 5'UTR could stimulate cap-independent translation. Notably, hypoxic stress and the treatment with mTOR inhibitors enhanced the translation-stimulating property of p16INK4a 5'UTR. RNA immunoprecipitation performed in melanoma-derived SK-Mel-28 and in a patient-derived lymphoblastoid cell line indicated that YBX1 can bind the wild type p16INK4a mRNA increasing its translation efficiency, particularly during hypoxic stress. Modulation of YBX1 expression further supported its involvement in cap-independent translation of the wild type p16INK4a but not a c.-42T>A variant. RNA SHAPE assays revealed local flexibility changes for the c.-42T>A variant at the predicted YBX1 binding site region. Our results indicate that p16INK4a 5'UTR contains a cellular IRES that can enhance mRNA translation efficiency, in part through YBX1.

The 5'-untranslated region of p16INK4a melanoma tumor suppressor acts as a cellular IRES, controlling mRNA translation under hypoxia through YBX1 binding / Bisio, Alessandra; Latorre, Elisa; Andreotti, Virginia; Paillerets, Brigitte Bressac de; Harland, Mark; Scarra, Giovanna Bianchi; Ghiorzo, Paola; Spitale, Robert C; Provenzani, Alessandro; Inga, Alberto. - In: ONCOTARGET. - ISSN 1949-2553. - 2015:(2015). [10.18632/oncotarget.5387]

The 5'-untranslated region of p16INK4a melanoma tumor suppressor acts as a cellular IRES, controlling mRNA translation under hypoxia through YBX1 binding

Bisio, Alessandra;Latorre, Elisa;Provenzani, Alessandro;Inga, Alberto
2015-01-01

Abstract

CDKN2A/p16INK4a is an essential tumor suppressor gene that controls cell cycle progression and replicative senescence. It is also the main melanoma susceptibility gene. Here we report that p16INK4a 5'UTR mRNA acts as a cellular Internal Ribosome Entry Site (IRES). The potential for p16INK4a 5'UTR to drive cap-independent translation was evaluated by dual-luciferase assays using bicistronic and monocistronic vectors. Results of reporters' relative activities coupled to control analyses for actual bicistronic mRNA transcription, indicated that the wild type p16INK4a 5'UTR could stimulate cap-independent translation. Notably, hypoxic stress and the treatment with mTOR inhibitors enhanced the translation-stimulating property of p16INK4a 5'UTR. RNA immunoprecipitation performed in melanoma-derived SK-Mel-28 and in a patient-derived lymphoblastoid cell line indicated that YBX1 can bind the wild type p16INK4a mRNA increasing its translation efficiency, particularly during hypoxic stress. Modulation of YBX1 expression further supported its involvement in cap-independent translation of the wild type p16INK4a but not a c.-42T>A variant. RNA SHAPE assays revealed local flexibility changes for the c.-42T>A variant at the predicted YBX1 binding site region. Our results indicate that p16INK4a 5'UTR contains a cellular IRES that can enhance mRNA translation efficiency, in part through YBX1.
2015
Bisio, Alessandra; Latorre, Elisa; Andreotti, Virginia; Paillerets, Brigitte Bressac de; Harland, Mark; Scarra, Giovanna Bianchi; Ghiorzo, Paola; Spitale, Robert C; Provenzani, Alessandro; Inga, Alberto
The 5'-untranslated region of p16INK4a melanoma tumor suppressor acts as a cellular IRES, controlling mRNA translation under hypoxia through YBX1 binding / Bisio, Alessandra; Latorre, Elisa; Andreotti, Virginia; Paillerets, Brigitte Bressac de; Harland, Mark; Scarra, Giovanna Bianchi; Ghiorzo, Paola; Spitale, Robert C; Provenzani, Alessandro; Inga, Alberto. - In: ONCOTARGET. - ISSN 1949-2553. - 2015:(2015). [10.18632/oncotarget.5387]
File in questo prodotto:
File Dimensione Formato  
Oncotarget p16 2015.pdf

accesso aperto

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Creative commons
Dimensione 1.91 MB
Formato Adobe PDF
1.91 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/119295
Citazioni
  • ???jsp.display-item.citation.pmc??? 10
  • Scopus 17
  • ???jsp.display-item.citation.isi??? 17
social impact