Tyrosine 402 phosphorylation of Pyk2 is involved in ionomycin-induced neurotransmitter release.
Protein tyrosine kinases, which are highly expressed in the central nervous system, are implicated in many neural processes. However, the relationship between protein tyrosine kinases and neurotransmitter release remains unknown. In this study, we found that ionomycin, a Ca²⁺ ionophore, concurrently induced asynchronous neurotransmitter release and phosphorylation of a non-receptor protein tyrosine kinase, proline-rich tyrosine kinase 2 (Pyk2), in clonal rat pheochromocytoma PC12 cells and cerebellar granule cells, whereas introduction of Pyk2 siRNA dramatically suppressed ionomycin-induced neurotransmitter release. Further study indicated that Tyr-402 (Y402) in Pyk2, instead of other tyrosine sites, underwent rapid phosphorylation after ionomycin induction in 1 min to 2 min. We demonstrated that the mutant of Pyk2 Y402 could abolish ionomycin-induced dopamine (DA) release by transfecting cells with recombinant Pyk2 and its mutants (Y402F, Y579F, Y580F, and Y881F). In addition, Src inhibition could prolong phosphorylation of Pyk2 Y402 and increase DA release. These findings suggested that Pyk2 was involved in ionomycin-induced neurotransmitter release through phosphorylation of Y402.
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Zhao
Z
Zhang
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Yun
Y
Zhang
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Zheng
Z
Mou
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Shifeng
S
Chu
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Xiaoyu
X
Chen
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China; Basic Medical College, Shanxi University of Traditional Chinese Medicine, Taiyuan, People's Republic of China.
Wenbin
W
He
Basic Medical College, Shanxi University of Traditional Chinese Medicine, Taiyuan, People's Republic of China.
Xiaofeng
X
Guo
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Yuhe
Y
Yuan
Department of Biochemistry, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
Masami
M
Takahashi
State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Department of Pharmacology, Institute of Materia Medica, and neuroscience center, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, People's Republic of China.
Naihong
N
Chen
D000818:Animals; D051418:Focal Adhesion Kinase 2 / Q000378:metabolism*; D015759:Ionomycin / Q000494:pharmacology*; D018377:Neurotransmitter Agents / Q000378:metabolism*; D016716:PC12 Cells; D010766:Phosphorylation / Q000187:drug effects; D019000:Phosphotyrosine / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D019061:src-Family Kinases / Q000378:metabolism
D018377:Neurotransmitter Agents; D034741:RNA, Small Interfering; D019000:Phosphotyrosine; D015759:Ionomycin; D051418:Focal Adhesion Kinase 2; D019061:src-Family Kinases