Repositório Científico do Instituto Nacional de Saúde >
Departamento de Genética Humana >
DGH - Posters/abstracts em congressos internacionais >

Please use this identifier to cite or link to this item:

Título: An upstream open reading frame regulates de translational efficiency of the human erythropoietin transcript
Autor: Barbosa, Cristina
Romão, Luísa
Palavras-chave: Genómica Funcional e Estrutural
Issue Date: 7-Oct-2012
Editora: Instituto Nacional de Saúde Doutor Ricardo Jorge, IP
Resumo: Among the various cis-acting elements present in the 5’ leader sequence of mRNAs there are upstream open reading frames (uORFs). Although their function is still poorly understood, they are known to downregulate the main ORF expression of several human transcripts that code for key regulatory genes. The human erythropoietin (EPO) is a glycoprotein that was initially characterized has a hormone mainly synthesized and released from the kidney, with a key role in hematopoiesis. However, many recent reports have implicated EPO in several non-hematopoietic functions and have shown its production in several other organs. Consequently, it might be used as a therapeutic target for the treatment of several human disorders. We found a natural occurring 14-codon-uORF on the human EPO transcript. Our belief is that understanding the molecular mechanisms through which the EPO uORF controls translation may be valuable in the determination of these EPO-based therapies. To explore the mechanisms by which EPO uORF controls translational efficiency, HepG2, HEK293 and REPC cells were transfected with several constructs carrying the luciferase reporter gene with the intact or disrupted EPO uORF, with or without the EPO 3’ untranslated region (3’UTR). Luciferase activity was measured by luminometry and normalized to the corresponding mRNA levels to obtain translation efficiencies. The mRNA levels were quantified by real-time RT-PCR. Furthermore, we also analyzed its response to several cell stress stimuli. Results show that the EPO uORF can decrease the main ORF translation efficiency in about 3-fold. In addition, our data support the conclusion that reinitiation, and in less extent leaky scanning, are responsible for the main ORF translation. In addition, the 3’UTR does not affect the role of the uORF, but it increases the luciferase levels, probably by stabilizing the mRNA. Specifically in REPC cells, translational inhibition mediated by the EPO uORF is overridden in response to chemical hypoxia, which is due to less recognition of the uAUG.
Arbitragem científica: yes
Appears in Collections:DGH - Posters/abstracts em congressos internacionais

Files in This Item:

File Description SizeFormat
Abstract Cristina Barbosa Heidelberg 2012.pdf36,57 kBAdobe PDFView/Open

Please give feedback about this item
FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpace
Formato BibTex MendeleyEndnote Logotipo do DeGóis 

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


  © 2010 - Todos os direitos reservados | Feedback Ministério da Saúde
Promotores do RCAAP   Financiadores do RCAAP

Fundação para a Ciência e a Tecnologia Universidade do Minho   Governo Português Ministério da Educação e Ciência PO Sociedade do Conhecimento (POSC) Portal oficial da União Europeia