Final answer:
CaMKII functions in long-term potentiation by phosphorylating AMPA receptors and associated proteins, leading to increased synaptic strength and the insertion of more AMPA receptors, thereby enhancing synaptic transmission, which is pivotal for learning and memory storage.
Step-by-step explanation:
Function of CaMKII in LTP
The function of CaMKII (Calcium/Calmodulin-dependent protein kinase II) in long-term potentiation (LTP) is crucial. During LTP, which is the persistent strengthening of synapses based on recent patterns of activity, high levels of calcium enter the postsynaptic neuron through NMDA receptors. This calcium influx triggers a cellular cascade that activates CaMKII among other kinases, leading to a series of events that ultimately enhance synaptic transmission.
CaMKII phosphorylates postsynaptic targets including AMPA receptors, thus increasing their single channel conduction. Additionally, it modulates the protein machinery that governs the number of postsynaptic AMPA receptors, enabling more nesting sites for new receptors. The selective potentiation of synapses by localized CaMKII activity is critical for synaptic plasticity and is believed to be one of the underlying mechanisms for memory storage and learning.
In summary, CaMKII plays a crucial role in LTP by phosphorylating various substrates that lead to the insertion of more AMPA receptors and by enhancing the responsiveness of the synapse, thereby facilitating more efficient synaptic transmission and strengthening synaptic connections that support the formation of long-term memory.