Resumen de Hallazgos

The work presented in this thesis raises a number of issues. We now know the region of eIF2Bε that associates with RGS2, and that phosphorylation of eIF2Bε at the GSK3 site increases the binding between the two proteins. For future studies, it would be of interest to investigate if other phosphorylation sites near GSK3 site, such as serine 525 can have an effect on RGS2-eIF2Bε interaction. We know that RGS2 also possess phosphorylation sites near its N-terminus 21, and therefore it would be worthwhile to investigate whether phosphorylation of RGS2 would have an effect on binding to eIF2Bε. In addition, we would like to pursue whether GSK3 may have a modulatory role in eIF2Bε activity through RGS2, and this would give us further insight into protein

interaction network. To test this we can employ endogenous co-immunoprecipitation method and observe whether knockdown of GSK3 can affect the amount of RGS2 bound to eIF2Bε.

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Appendix