Riboproteomic Approaches to Understanding IRES Elements - Biophysical Approaches to Translational Control of Gene Expression - page 110

6.5 Concluding Remarks

ITAFs are RNA-binding proteins that shuttle between the nucleus and the cytoplasm,
activating or repressing the expression of proteins critical in the cellular response to
growth, nutritional, environmental, and proliferation signals. With a few exceptions
of ITAFs interacting with viral IRES, the precise role played by ITAFs is not well
understood. It has been proposed that ITAFs help to remodel the RNA structure in a
way that enhances its affinity for components of the translation machinery, or that
they substitute some canonical factors providing functional bridges between the
mRNA and the ribosomal subunits. Elucidating the function of ITAFs demands a
deep understanding of their RNA targets and their protein partners with potential
modifications. In this regard, implementation of proteomic approaches will continue
to help understanding the integrated action of ITAFs on mRNA targets.

Acknowledgments This work was supported by grant BFU2011-25437, CSD2009-00080, and
by an Institutional grant from Fundación Ramón Areces.

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