TY - JOUR
T1 - Phosphoproteomic of the acetylcholine pathway enables discovery of the PKC-β-PIX-Rac1-PAK cascade as a stimulatory signal for aversive learning
AU - Yamahashi, Yukie
AU - Lin, You Hsin
AU - Mouri, Akihiro
AU - Iwanaga, Sho
AU - Kawashima, Kazuhiro
AU - Tokumoto, Yuya
AU - Watanabe, Yo
AU - Faruk, Md Omar
AU - Zhang, Xinjian
AU - Tsuboi, Daisuke
AU - Nakano, Takashi
AU - Saito, Naoaki
AU - Nagai, Taku
AU - Yamada, Kiyofumi
AU - Kaibuchi, Kozo
N1 - Publisher Copyright:
© 2022, The Author(s).
PY - 2022/8
Y1 - 2022/8
N2 - Acetylcholine is a neuromodulator critical for learning and memory. The cholinesterase inhibitor donepezil increases brain acetylcholine levels and improves Alzheimer’s disease (AD)-associated learning disabilities. Acetylcholine activates striatal/nucleus accumbens dopamine receptor D2-expressing medium spiny neurons (D2R-MSNs), which regulate aversive learning through muscarinic receptor M1 (M1R). However, how acetylcholine stimulates learning beyond M1Rs remains unresolved. Here, we found that acetylcholine stimulated protein kinase C (PKC) in mouse striatal/nucleus accumbens. Our original kinase-oriented phosphoproteomic analysis revealed 116 PKC substrate candidates, including Rac1 activator β-PIX. Acetylcholine induced β-PIX phosphorylation and activation, thereby stimulating Rac1 effector p21-activated kinase (PAK). Aversive stimulus activated the M1R-PKC-PAK pathway in mouse D2R-MSNs. D2R-MSN-specific expression of PAK mutants by the Cre-Flex system regulated dendritic spine structural plasticity and aversive learning. Donepezil induced PAK activation in both accumbal D2R-MSNs and in the CA1 region of the hippocampus and enhanced D2R-MSN-mediated aversive learning. These findings demonstrate that acetylcholine stimulates M1R-PKC-β-PIX-Rac1-PAK signaling in D2R-MSNs for aversive learning and imply the cascade’s therapeutic potential for AD as aversive learning is used to preliminarily screen AD drugs.
AB - Acetylcholine is a neuromodulator critical for learning and memory. The cholinesterase inhibitor donepezil increases brain acetylcholine levels and improves Alzheimer’s disease (AD)-associated learning disabilities. Acetylcholine activates striatal/nucleus accumbens dopamine receptor D2-expressing medium spiny neurons (D2R-MSNs), which regulate aversive learning through muscarinic receptor M1 (M1R). However, how acetylcholine stimulates learning beyond M1Rs remains unresolved. Here, we found that acetylcholine stimulated protein kinase C (PKC) in mouse striatal/nucleus accumbens. Our original kinase-oriented phosphoproteomic analysis revealed 116 PKC substrate candidates, including Rac1 activator β-PIX. Acetylcholine induced β-PIX phosphorylation and activation, thereby stimulating Rac1 effector p21-activated kinase (PAK). Aversive stimulus activated the M1R-PKC-PAK pathway in mouse D2R-MSNs. D2R-MSN-specific expression of PAK mutants by the Cre-Flex system regulated dendritic spine structural plasticity and aversive learning. Donepezil induced PAK activation in both accumbal D2R-MSNs and in the CA1 region of the hippocampus and enhanced D2R-MSN-mediated aversive learning. These findings demonstrate that acetylcholine stimulates M1R-PKC-β-PIX-Rac1-PAK signaling in D2R-MSNs for aversive learning and imply the cascade’s therapeutic potential for AD as aversive learning is used to preliminarily screen AD drugs.
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U2 - 10.1038/s41380-022-01643-2
DO - 10.1038/s41380-022-01643-2
M3 - Article
C2 - 35665767
AN - SCOPUS:85131302454
SN - 1359-4184
VL - 27
SP - 3479
EP - 3492
JO - Molecular Psychiatry
JF - Molecular Psychiatry
IS - 8
ER -
