Ya-Bo Zhao, Shi-Zhe Wang, Wen-Ting Guo, Le Wang, Xun Tang, Jin-Nan Li, Lin Xu, Qi-Xin Zhou
{"title":"海马二肽基肽酶 9 双向调节与突触可塑性有关的记忆","authors":"Ya-Bo Zhao, Shi-Zhe Wang, Wen-Ting Guo, Le Wang, Xun Tang, Jin-Nan Li, Lin Xu, Qi-Xin Zhou","doi":"10.1016/j.jare.2024.09.031","DOIUrl":null,"url":null,"abstract":"<h3>Introduction</h3>Subtypes of the dipeptidyl peptidase (DPP) family, such as DPP4, are reportedly associated with memory impairment. DPP9 is widely distributed in cells throughout the body, including the brain. However, whether DPP9 regulates memory has not yet been elucidated.<h3>Objectives</h3>This study aimed to elucidate the role of DPP9 in memory, as well as the underlying molecular mechanism.<h3>Methods</h3>We performed immunofluorescence on mouse brains to explore the distribution of DPP9 in different brain regions and used AAV vectors to construct knockdown and overexpression models. The effects of changing DPP9 expression on memory were demonstrated through behavioral experiments. Finally, we used electrophysiology, proteomics and affinity purification mass spectrometry (AP-MS) to study the molecular mechanism by which DPP9 affects memory.<h3>Results</h3>Here, we report that DPP9, which is found almost exclusively in neurons, is expressed and has enzyme activity in many brain regions, especially in the hippocampus. Hippocampal DPP9 expression increases after fear memory formation. Fear memory was impaired by DPP9 knockdown and enhanced by DPP9 protein overexpression in the hippocampus. According to subsequent hippocampal proteomics, multiple pathways, including the peptidase pathway, which can be bidirectionally regulated by DPP9. DPP9 directly interacts with its enzymatic substrate neuropeptide Y (NPY) in neurons. Hippocampal long-term potentiation (LTP) is also bidirectionally regulated by DPP9. Moreover, inhibiting DPP enzyme activity impaired both LTP and memory. In addition, AP-MS revealed that DPP9-interacting proteins are involved in the functions of dendritic spines and axons. By combining AP-MS and proteomics, DPP9 was shown to play a role in regulating actin functions.<h3>Conclusion</h3>Taken together, our findings reveal that DPP9 affects the CNS not only through enzymatic activity but also through protein–protein interactions. This study provides new insights into the molecular mechanisms of memory and DPP family functions.","PeriodicalId":14952,"journal":{"name":"Journal of Advanced Research","volume":null,"pages":null},"PeriodicalIF":11.4000,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Hippocampal dipeptidyl peptidase 9 bidirectionally regulates memory associated with synaptic plasticity\",\"authors\":\"Ya-Bo Zhao, Shi-Zhe Wang, Wen-Ting Guo, Le Wang, Xun Tang, Jin-Nan Li, Lin Xu, Qi-Xin Zhou\",\"doi\":\"10.1016/j.jare.2024.09.031\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<h3>Introduction</h3>Subtypes of the dipeptidyl peptidase (DPP) family, such as DPP4, are reportedly associated with memory impairment. DPP9 is widely distributed in cells throughout the body, including the brain. However, whether DPP9 regulates memory has not yet been elucidated.<h3>Objectives</h3>This study aimed to elucidate the role of DPP9 in memory, as well as the underlying molecular mechanism.<h3>Methods</h3>We performed immunofluorescence on mouse brains to explore the distribution of DPP9 in different brain regions and used AAV vectors to construct knockdown and overexpression models. The effects of changing DPP9 expression on memory were demonstrated through behavioral experiments. Finally, we used electrophysiology, proteomics and affinity purification mass spectrometry (AP-MS) to study the molecular mechanism by which DPP9 affects memory.<h3>Results</h3>Here, we report that DPP9, which is found almost exclusively in neurons, is expressed and has enzyme activity in many brain regions, especially in the hippocampus. Hippocampal DPP9 expression increases after fear memory formation. Fear memory was impaired by DPP9 knockdown and enhanced by DPP9 protein overexpression in the hippocampus. According to subsequent hippocampal proteomics, multiple pathways, including the peptidase pathway, which can be bidirectionally regulated by DPP9. DPP9 directly interacts with its enzymatic substrate neuropeptide Y (NPY) in neurons. Hippocampal long-term potentiation (LTP) is also bidirectionally regulated by DPP9. Moreover, inhibiting DPP enzyme activity impaired both LTP and memory. In addition, AP-MS revealed that DPP9-interacting proteins are involved in the functions of dendritic spines and axons. By combining AP-MS and proteomics, DPP9 was shown to play a role in regulating actin functions.<h3>Conclusion</h3>Taken together, our findings reveal that DPP9 affects the CNS not only through enzymatic activity but also through protein–protein interactions. This study provides new insights into the molecular mechanisms of memory and DPP family functions.\",\"PeriodicalId\":14952,\"journal\":{\"name\":\"Journal of Advanced Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":11.4000,\"publicationDate\":\"2024-10-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Advanced Research\",\"FirstCategoryId\":\"103\",\"ListUrlMain\":\"https://doi.org/10.1016/j.jare.2024.09.031\",\"RegionNum\":1,\"RegionCategory\":\"综合性期刊\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MULTIDISCIPLINARY SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Advanced Research","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.1016/j.jare.2024.09.031","RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
Subtypes of the dipeptidyl peptidase (DPP) family, such as DPP4, are reportedly associated with memory impairment. DPP9 is widely distributed in cells throughout the body, including the brain. However, whether DPP9 regulates memory has not yet been elucidated.
Objectives
This study aimed to elucidate the role of DPP9 in memory, as well as the underlying molecular mechanism.
Methods
We performed immunofluorescence on mouse brains to explore the distribution of DPP9 in different brain regions and used AAV vectors to construct knockdown and overexpression models. The effects of changing DPP9 expression on memory were demonstrated through behavioral experiments. Finally, we used electrophysiology, proteomics and affinity purification mass spectrometry (AP-MS) to study the molecular mechanism by which DPP9 affects memory.
Results
Here, we report that DPP9, which is found almost exclusively in neurons, is expressed and has enzyme activity in many brain regions, especially in the hippocampus. Hippocampal DPP9 expression increases after fear memory formation. Fear memory was impaired by DPP9 knockdown and enhanced by DPP9 protein overexpression in the hippocampus. According to subsequent hippocampal proteomics, multiple pathways, including the peptidase pathway, which can be bidirectionally regulated by DPP9. DPP9 directly interacts with its enzymatic substrate neuropeptide Y (NPY) in neurons. Hippocampal long-term potentiation (LTP) is also bidirectionally regulated by DPP9. Moreover, inhibiting DPP enzyme activity impaired both LTP and memory. In addition, AP-MS revealed that DPP9-interacting proteins are involved in the functions of dendritic spines and axons. By combining AP-MS and proteomics, DPP9 was shown to play a role in regulating actin functions.
Conclusion
Taken together, our findings reveal that DPP9 affects the CNS not only through enzymatic activity but also through protein–protein interactions. This study provides new insights into the molecular mechanisms of memory and DPP family functions.
期刊介绍:
Journal of Advanced Research (J. Adv. Res.) is an applied/natural sciences, peer-reviewed journal that focuses on interdisciplinary research. The journal aims to contribute to applied research and knowledge worldwide through the publication of original and high-quality research articles in the fields of Medicine, Pharmaceutical Sciences, Dentistry, Physical Therapy, Veterinary Medicine, and Basic and Biological Sciences.
The following abstracting and indexing services cover the Journal of Advanced Research: PubMed/Medline, Essential Science Indicators, Web of Science, Scopus, PubMed Central, PubMed, Science Citation Index Expanded, Directory of Open Access Journals (DOAJ), and INSPEC.