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Yamazaki A, Kawashima A, Honda T, Kohama T, Murakami C, Sakane F, Murayama T, Nakamura H. Identification and characterization of diacylglycerol kinase ζ as a novel enzyme producing ceramide-1-phosphate. Biochim Biophys Acta Mol Cell Biol Lipids 2023; 1868:159307. [PMID: 36906254 DOI: 10.1016/j.bbalip.2023.159307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/16/2023] [Accepted: 03/01/2023] [Indexed: 03/13/2023]
Abstract
Ceramide-1-phosphate (C1P) is a sphingolipid formed by the phosphorylation of ceramide; it regulates various physiological functions, including cell survival, proliferation, and inflammatory responses. In mammals, ceramide kinase (CerK) is the only C1P-producing enzyme currently known. However, it has been suggested that C1P is also produced by a CerK-independent pathway, although the identity of this CerK-independent C1P was unknown. Here, we identified human diacylglycerol kinase (DGK) ζ as a novel C1P-producing enzyme and demonstrated that DGKζ catalyzes the phosphorylation of ceramide to produce C1P. Analysis using fluorescently labeled ceramide (NBD-ceramide) demonstrated that only DGKζ among ten kinds of DGK isoforms increased C1P production by transient overexpression of the DGK isoforms. Furthermore, an enzyme activity assay using purified DGKζ revealed that DGKζ could directly phosphorylate ceramide to produce C1P. Furthermore, genetic deletion of DGKζ decreased the formation of NBD-C1P and the levels of endogenous C18:1/24:1- and C18:1/26:0-C1P. Interestingly, the levels of endogenous C18:1/26:0-C1P were not decreased by the knockout of CerK in the cells. These results suggest that DGKζ is also involved in the formation of C1P under physiological conditions.
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Affiliation(s)
- Ayako Yamazaki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Ayane Kawashima
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Takuya Honda
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Takafumi Kohama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Chiaki Murakami
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan; Institute for Advanced Academic Research, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Fumio Sakane
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Toshihiko Murayama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Hiroyuki Nakamura
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
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Wang P, Ma K, Yang L, Zhang G, Ye M, Wang S, Wei S, Chen Z, Gu J, Zhang L, Niu J, Tao S. Predicting signaling pathways regulating demyelination in a rat model of lithium-pilocarpine-induced acute epilepsy: A proteomics study. Int J Biol Macromol 2021; 193:1457-1470. [PMID: 34742844 DOI: 10.1016/j.ijbiomac.2021.10.209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 11/18/2022]
Abstract
Demyelination is observed in animal models of intractable epilepsy (IE). Epileptogenesis damages the myelin sheath and dysregulates oligodendrocyte precursor cell (OPC) development. However, the molecular pathways regulating demyelination in epilepsy are unclear. Here, we predicted the molecular mechanisms regulating demyelination in a rat model of lithium-pilocarpine hydrochloride-induced epilepsy. We identified DGKA/Mboat2/Inpp5j and NOS/Keratin 28 as the main target molecules that regulate demyelination via glycerolipid and glycerophospholipid metabolism, phosphatidylinositol signaling, and estrogen signaling in demyelinated forebrain slice cultures (FSCs). In seizure-like FCSs, the actin cytoskeleton was regulated by Cnp and MBP via Pak4/Tmsb4x (also known as Tβ4) and Kif5c/Kntc1. Tβ4 possibly prevented OPC differentiation and maturation and inhibited MBP phosphorylation via the p38MAPK/ERK1/JNK1 pathway. The MAPK signaling pathway was more likely activated in seizure-like FCSs than in demyelinated FCSs. pMBP expression was decreased in the hippocampus of lithium-pilocarpine hydrochloride-induced acute epilepsy rats. The expression of remyelination-related factors was suppressed in the hippocampus and corpus callosum in lithium-pilocarpine hydrochloride-induced epilepsy rats. These findings suggest that the actin cytoskeleton, Tβ4, and MAPK signaling pathways regulate the decrease in pMBP in the hippocampus in a rat model of epilepsy. Our results indicate that regulating the actin cytoskeleton, Tβ4, and MAPK signaling pathways may facilitate the prevention of demyelination in IE.
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Affiliation(s)
- Peng Wang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan 750004, China.
| | - Kang Ma
- Department of Anatomy, Ningxia Medical University, Yinchuan 750004, China
| | - Lu Yang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan 750004, China
| | - Guodong Zhang
- School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, China
| | - Mengyi Ye
- Ningxia Medical University College of Traditional Chinese Medicine, Yinchuan 750004, Ningxia, China
| | - Siqi Wang
- School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, China
| | - Shuangshuang Wei
- School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, China
| | - Zhangping Chen
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan 750004, China
| | - Jinghai Gu
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan 750004, China
| | - Lianxiang Zhang
- Department of Anatomy, Ningxia Medical University, Yinchuan 750004, China
| | - Jianguo Niu
- Department of Anatomy, Ningxia Medical University, Yinchuan 750004, China.
| | - Sun Tao
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan 750004, China; Department of Neurosurgery, General Hospital of Ningxia Medical University, 804 Shengli Street, Yinchuan 750004, Ningxia, China.
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