The presence of specific mRNAs in dendrites and at synapses is well established, but a direct and reliable demonstration that they are associated with polysomes is still missing. To address this point we analyzed the polysomal association of the mRNAs for the alpha-subunit of Ca2+/calmodulin-dependent protein kinase II (alpha-CaMKII), for type 1 inositol 1,4,5-trisphosphate receptor (InsP3R1) and for the activity-regulated cytoskeleton-associated protein (Arc) in a synaptosomal preparation devoid of contaminating material from neuronal and glial perikarya. We show that a fraction of alpha-CaMKII, InsP3R1, and Arc mRNAs present in synaptosomes is indeed associated with polysomes. Moreover, we show that polysomal association of alpha-CaMKII mRNA, but not InsP3R1 and Arc mRNAs, increases with depolarization of the synaptosomal membrane. Finally, we show that the synthesis of alpha-CaMKII protein increases with stimulation. Dendritic mRNA recruitment onto polysomes in response to synaptic stimulation might represent one of the mechanisms underlying the processes of learning and memory.
Bagni, C., Mannucci, L., Dotti, C.g., Amaldi, F. (2000). Chemical stimulation of synaptosomes modulates alpha-Ca2+/calmodulin-dependent protein kinase II mRNA association to polysomes. THE JOURNAL OF NEUROSCIENCE, 20(10), 1-6.
Chemical stimulation of synaptosomes modulates alpha-Ca2+/calmodulin-dependent protein kinase II mRNA association to polysomes
BAGNI, CLAUDIA;AMALDI, FRANCESCO
2000-01-01
Abstract
The presence of specific mRNAs in dendrites and at synapses is well established, but a direct and reliable demonstration that they are associated with polysomes is still missing. To address this point we analyzed the polysomal association of the mRNAs for the alpha-subunit of Ca2+/calmodulin-dependent protein kinase II (alpha-CaMKII), for type 1 inositol 1,4,5-trisphosphate receptor (InsP3R1) and for the activity-regulated cytoskeleton-associated protein (Arc) in a synaptosomal preparation devoid of contaminating material from neuronal and glial perikarya. We show that a fraction of alpha-CaMKII, InsP3R1, and Arc mRNAs present in synaptosomes is indeed associated with polysomes. Moreover, we show that polysomal association of alpha-CaMKII mRNA, but not InsP3R1 and Arc mRNAs, increases with depolarization of the synaptosomal membrane. Finally, we show that the synthesis of alpha-CaMKII protein increases with stimulation. Dendritic mRNA recruitment onto polysomes in response to synaptic stimulation might represent one of the mechanisms underlying the processes of learning and memory.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.