Application of polysome profiling analysis in the study of synaptic protein translation

摘要

Application of polysome profiling analysis in the study of synaptic protein translation In the nervous system, synapses play a key role in information transfer within brain networks and are most closely correlated with brain functions such as learning and memory. Translation is an essential biological process for the formation, plasticity and function of synapses. Several studies have indicated that trans- lational dysregulation is linked with neurodegenerative diseases such as Alzheimer’s disease. Polysome profiling separates the sub- cellular fractions of the ribosomes using sucrose density gradient ultracentrifugation, which is an effective method for studying the translation state of proteins of interest. However, application of this technique to study translation of specific synaptic proteins is just starting to be reported. In the current study, we utilized polysome profiling to separate ribonucleoproteins, monosomes and polysomes from adult mouse hippocampus. Subsequently, we assessed the distribution of mRNAs of synaptic proteins in different fractions using qPCR. The result showed that different glutamate receptor subunits have different distribution profiles. For exam- ple, the mRNAs of Grin1, Grin2a and Grin2b are more distributed in the polysome fraction, whereas more Grial1 is associated with the monosomes. Further studies are ongoing regarding the change of polysome distribution of these mRNAs in response to synaptic activity.