Gutiérrez-Escolano AL

Language: Spanish
References: 17
Page: 12-19
PDF size: 126.42 Kb.

ABSTRACT

Translation initiates by two distinct mechanisms: the cap-depending scanning where the ribosome binds to the cap structure located at the 5' end of the mRNA and the IRES-dependent translation, where the ribosome binds to an internal region of the mRNA. The IRES is a sequence of RNA with complex secondary structures, located within the mRNA 5' UTR that allows the ribosome to be recruited near the initiation codon. mRNAs with IRES, which were first identified in virus, can be translated when the cap dependent translation has been inhibited, as is the case, during an infection. Some cellular mRNAs also contain IRES and are expressed during cell growth, cell death, viral infections and even under some events of cellular stress. During these conditions the expression of certain proteins represents a safe strategy to ensure cellular survey or programmed cell death or apoptosis.

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