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bioRxiv · 10.1101/169425

Experience-dependent translational state defined by cell type-specific ribosome profiling

Eacker, S. M.·Crawford, K.·Brichta, L.·Riessland, M.·Ingolia, N. T.·Greengard, P.·Dawson, T. M.·Dawson, V. L.
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Abstract

Experience-dependent neuronal activity regulates the translation of mRNA, supporting memory formation. We have developed a new method termed translating ribosome affinity purification and ribosome profiling (TRiP) which allows us to determine cell type-specific ribosome occupancy of mRNA with nucleotide resolution. Using TRiP we show that a memory-inducing experience creates a distinct translational state in mouse CA1 pyramidal cells. The experience-dependent translation state is characterized by enhanced translation of protein-coding open reading frames (ORFs) including numerous components of the actin cytoskeleton and calcium/calmodulin binding proteins, and by decreased translation of a defined subset of genes containing upstream ORFs (uORFs). Using animals heterozygous for an unphosphorylatable allele of the eukaryotic translation initiation factor 2 (eIF2), we show that dephosphorylation of eIF2 contributes significantly to the experience-dependent translation state. These observations demonstrate that TRiP is a valuable methodology for studying physiologically relevant changes in translational state in genetically defined cell types.

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Eacker, S. M., Crawford, K., Brichta, L., Riessland, M., Ingolia, N. T., Greengard, P., Dawson, T. M., Dawson, V. L.. 2017-07-28. Experience-dependent translational state defined by cell type-specific ribosome profiling. https://doi.org/10.1101/169425

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