Looking at the effects of RIM1a which is a protein involved in neurotransmitter release. Any ideas as to why its total phosphorylation decreases as the rats develop?
Many thanks
Image; https://i.gyazo.com/16170fd79bd1f96517e028dfa2e70fbf.png
Paper; http://www.cell.com/cell/pdf/S0092-8674(03)00727-X.pdf
Here are a couple Wikipedia articles that might help out:
Critical period - Critical period: the idea that certain types of plasticity in the nervous system occur only at certain "critical" times.
Long-term potentiation - LTP, talked a lot about in the paper you linked: it's a mechanism for strengthening of synaptic connections.
Synaptic pruning - # synapses/strength of synapses tend to decrease from adolescence to adulthood
The paper you linked talks a lot about the role of phosphorylated RIM1a in LTP. Without knowing more specifically about this protein, and from just a glance at the paper you linked, I'd suspect that RIM1a is phosphorylated during periods of increased LTP, particularly earlier in development, and as animals age and their brains go into the synaptic pruning phase, LTP is downregulated overall, and one of mechanisms could be the lack of phoshporylated RIM1a.
