Phospholipase D1 Signaling: Essential Roles in Neural Stem Cell Differentiation

Park, Shin-Young,Han, Joong-Soo Springer US 2018 Journal of molecular neuroscience Vol.64 No.3

<P>Phospholipase D1 (PLD1) is generally accepted as playing an important role in the regulation of multiple cell functions, such as cell growth, survival, differentiation, membrane trafficking, and cytoskeletal organization. Recent findings suggest that PLD1 also plays an important role in the regulation of neuronal differentiation of neuronal cells. Moreover, PLD1-mediated signaling molecules dynamically regulate the neuronal differentiation of neural stem cells (NSCs). Rho family GTPases and Ca<SUP>2+</SUP>-dependent signaling, in particular, are closely involved in PLD1-mediated neuronal differentiation of NSCs. Moreover, PLD1 has a significant effect on the neurogenesis of NSCs via the regulation of SHP-1/STAT3 activation. Therefore, PLD1 has now attracted significant attention as an essential neuronal signaling molecule in the nervous system. In the current review, we summarize recent findings on the regulation of PLD1 in neuronal differentiation and discuss the potential role of PLD1 in the neurogenesis of NSCs.</P>

The hydrophobic amino acids involved in the interdomain association of phospholipase D1 regulate the shuttling of phospholipase D1 from vesicular organelles into the nucleus

장영훈,민도식 생화학분자생물학회 2012 Experimental and molecular medicine Vol.44 No.10

Phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine to generate the lipid second messenger, phosphatidic acid. PLD is localized in most cellular organelles, where it is likely to play different roles in signal transduction. PLD1 is primarily localized in vesicular structures such as endosomes, lysosomes and autophagosomes. However, the factors defining its localization are less clear. In this study, we found that four hydrophobic residues present in the N-terminal HKD catalytic motif of PLD1, which is involved in intramolecular association, are responsible for vesicular localization. Site-directed mutagenesis of the residues dramatically disrupted vesicular localization of PLD1. Interestingly, the hydrophobic residues of PLD1are also involved in the interruption of its nuclear localization. Mutation of the residues increased the association of PLD1 with importin-β, which is known to mediate nuclear importation, and induced the localization of PLD1 from vesicles into the nucleus. Taken together, these data suggest that the ydrophobic amino acids involved in the interdomain association of PLD1 are required for vesicular localization and disturbance of its nuclear localization.

Endothelial Deletion of Phospholipase D2 Reduces Hypoxic Response and Pathological Angiogenesis

Ghim, Jaewang,Moon, Jin-Sook,Lee, Chang Sup,Lee, Junyeop,Song, Parkyong,Lee, Areum,Jang, Jin-Hyeok,Kim, Dayea,Yoon, Jong Hyuk,Koh, Young Jun,Chelakkot, Chaithanya,Kang, Byung Jun,Kim, Jung-Min,Kim, Ky American Heart Association, Inc. 2014 Arteriosclerosis, thrombosis, and vascular biology Vol.34 No.8

<P><B>Objective—</B></P><P>Aberrant regulation of the proliferation, survival, and migration of endothelial cells (ECs) is closely related to the abnormal angiogenesis that occurs in hypoxia-induced pathological situations, such as cancer and vascular retinopathy. Hypoxic conditions and the subsequent upregulation of hypoxia-inducible factor-1α and target genes are important for the angiogenic functions of ECs. Phospholipase D2 (PLD2) is a crucial signaling mediator that stimulates the production of the second messenger phosphatidic acid. PLD2 is involved in various cellular functions; however, its specific roles in ECs under hypoxia and in vivo angiogenesis remain unclear. In the present study, we investigated the potential roles of PLD2 in ECs under hypoxia and in hypoxia-induced pathological angiogenesis in vivo.</P><P><B>Approach and Results—</B></P><P><I>Pld2</I> knockout ECs exhibited decreased hypoxia-induced cellular responses in survival, migration, and thus vessel sprouting. Analysis of hypoxia-induced gene expression revealed that PLD2 deficiency disrupted the upregulation of hypoxia-inducible factor-1α target genes, including <I>VEGF</I>, <I>PFKFB3</I>, <I>HMOX-1</I>, and <I>NTRK2</I>. Consistent with this, PLD2 contributed to hypoxia-induced hypoxia-inducible factor-1α expression at the translational level. The roles of PLD2 in hypoxia-induced in vivo pathological angiogenesis were assessed using oxygen-induced retinopathy and tumor implantation models in endothelial-specific <I>Pld2</I> knockout mice. <I>Pld2</I> endothelial-specific knockout retinae showed decreased neovascular tuft formation, despite a larger avascular region. Tumor growth and tumor blood vessel formation were also reduced in <I>Pld2</I> endothelial-specific knockout mice.</P><P><B>Conclusions—</B></P><P>Our findings demonstrate a novel role for endothelial PLD2 in the survival and migration of ECs under hypoxia via the expression of hypoxia-inducible factor-1α and in pathological retinal angiogenesis and tumor angiogenesis in vivo.</P>

Carbachol-induced Phosphorylation of Phospholipase D1 through Protein Kinase C is required for the Activation in COS-7 cells

Lee, Byoung-Dae,Kim, Yong,Han, Jung-Min,Suh, Pann-Ghill,Ryu, Sung-Ho Korean Society for Biochemistry and Molecular Biol 2001 Journal of biochemistry and molecular biology Vol.34 No.2

Phospholiapse D (PLD), and phosphatidic acid generated by it, have been implicated in receptor-mediated intracellular signaling. Carbachol (CCh) is known to activate PLD1, and protein kinase C (PKC) is known to mediate in this signaling pathway In recent reports (Kim et al., 1999b; Kim et al., 2000), we published our observations of the direct phosphorylation of PLD1 by PKC and we described the phosphorylation-dependent regulation of PLD1 activity. In this study, we investigated the phasphorylation and compartmentalization of PLD1 in terms of CCh signaling in M3 muscarinic receptor (M3R)-expressing COS-7 cells. CCh treatment of COS-7 cells transiently coexpressing PLD1 and M3R stimulated PLD1 activity and induced direct phosphorylation of PLD1 by PKC. The CCh-induced activation and phosphorylation of PLD1 was completely blocked upon pretreatment of the cells with PKC-specific inhibitors. We looked at the localization of the PLD1 phosphorylation by PKC and found that PLD1 was mainly located in the caveolin-enriched membrane (CEM) fraction. Based on these results, we conclude that CCh induces the activation and phosphorylation of PLD1 via PKC and that the phosphorylation of PLD1 occurs in caveolae.

The Inhibitory Mechanism of Aloe Glycoprotein (NY945) on the Mediator Release in the Guinea Pig Lung Mast Cell Activated with Antigen-Antibody Complexes

Jai Youl Ro,Byung Chul Lee,Myung Hee Chung,Seung Ki Lee,Chung Ki Sung,Kyung Hwan Kim,Young In Park 대한생리학회-대한약리학회 1998 The Korean Journal of Physiology & Pharmacology Vol.2 No.1

It has been reported that the g1ycoprotein extracted from A10e has strong anti-inflammatory response,However, there has been no research report yet about the effect of A10e on allergic hypersensitivity reactivity, By using guinea pig 1ung mast cells, this study aimed to examine the effects of A10e g1ycoprotein (NY945) on the mediator re1eases caused by mast cell activation, and a1so aimed to assess the effects of NY945 on the mechanism of mediator re1eases in the mast cell activation. We partially purified mast cell from guinea pig 1ung tissues by using the enzyme digestion, the rough and the discontinuous density percoll gradient method. Mast cells were sensitized with IgG1 (anti-OA) and challenged with ova1bumin. Histamine was assayed by fluorometric ana1yzer, 1eukotrienes by radioimmunoassay. The phospholipase D activity was assessed by the production of 1abe1ed phosphatidy1alcoho1. The amount of mass 1,2-diacy1g1ycero1 (DAG) was measured by the eH]DAG produced when pre1abe1ed with eH]myristic acid. The phosph01ipid methy1ation was assessed by measuring the incorporation of the eH]methy1 moiety into phosph01ipids of cellu1ar membranes. Pretreatment of NY945 (10 μg) significant1y decreased histamine and 1eukotrienes re1eases during mast cell activation. The decrease of histamine re1ease was stronger than that of 1eukotriene during mast cell activation. The phospholipase D activity increased by the mast cell activation was decreased by the dose-dependent manner in the pretreatment of NY945. The amount of DAG produced by PLC activity was decreased by NY945 pretreatment. The amount of mass 1, 2-diacy1g1ycero1 produced by activation of mast cells was decreased in the pretreatment of NY945. NY945 pretreatment strong1y inhibited the incorporation of the eH]methy1 moiety into phosph01ipids. The data suggest that NY945 purified from A10e inhibi엄 in part an increase of 1, 2-diacy1g1ycero1 which is produced by activating mast cells with antigen-antibody reactions, which is mediated via phosphatidylcholinephospholipase D and phosphatidylinosit01-phospholipase C systems, and then followed by the inhibition of histamine re1ease. Furthermore, NY945 reduces the production of phosphatidylch01ine by inhibiting the methy1transferase 1 and II, which decreases the conversion of phosphatidylcho1ine into arachidonic acid and inhibits the production of 1eukotrienes.

Autoregulation of phospholipase D activity is coupled to selective induction of phospholipase D1 expression to promote invasion of breast cancer cells

Kang, Dong Woo,Park, Mi Hee,Lee, Young Jun,Kim, Hyung Sik,Lindsley, Craig W.,Alex Brown, H.,Min, Do Sik Wiley Subscription Services, Inc., A Wiley Company 2011 International journal of cancer: Journal internati Vol.128 No.4

<P><B>Abstract</B></P><P>Phospholipase D (PLD) is an important signaling enzyme implicated in the control of many biological processes, including cell proliferation and survival. Despite the importance of the duration and amplitude of PLD signaling in carcinogenesis, mechanisms that regulate PLD expression remain poorly understood. In our study, we define the regulatory components of the machinery that specifies selective PLD1 induction <I>via</I> signals propagated through PLD activity. We demonstrate for the first time that establishment of a positive feedback loop that is dependent on enzymatic activity originating from both PLD1 and PLD2 isozymes enhances selective expression of PLD1, but not PLD2. Phosphatidic acid, the product of PLD activity, leads to an increase in the Ras‐ERK/PI3K‐NFκB signaling cascade and enhances binding of NFκB to the PLD1 promoter, consequently inducing selective PLD1 expression in SK‐BR3 breast cancer cells. Moreover, selective PLD inhibitor suppressed epidermal growth factor‐induced matrix metalloproteinase upregulation and invasion by inhibiting PLD1 expression. In conclusion, we propose that autoregulation of PLD activity might be coupled to induction of PLD1 expression, and thereby play a role in carcinogenesis.</P>

Increased expression of phospholipase D1 in the spinal cords of rats with experimental autoimmune encephalomyelitis

Ahn, Meejung,Min, Do Sik,Kang, Jongchul,Jung, Kyungsook,Shin, Taekyun 제주대학교 생명과학기술혁신센터 2002 제주생명과학연구 Vol.5 No.-

Phospholipase D1 (PLD1) expression was studied in the central nervous system (CNS) under the condition of induced experimental autoimmune encephalomyelitis (EAE) in Lewis rats. After inducing EAE, the expression of PLD1 was analyzed by Western blot and immunohistochemistry. Western blot analysis showed that expression of the isozymes PLD1 significantly increased in the spinal cord at the peak stage of EAE, and declined thereafter. Immunohistochemistry showed that PLD1 ­ positive cells increased in number in EAE lesions, which consisted mainly of ED1 ­ positive macro ­ phages and glial fibrillary acidic protein ­ positive astrocytes. In contrast, PLD1 was only weakly expressed in some spinal cord astrocytes in control rats. These results suggest that PLD1 is increased in autoimmune CNS inflammation, and possibly involved in the activation of macrophages and astrocytes in EAE lesions. ⓒ 2001 Elsevier Science Ireland Ltd, All rights reserved.

Enhancement of ATP-induced Currents by Phospholipase D1 Overexpressed in PC12 Cells

Park, Jin-Bong,Kim, Young-Rae,Jeon, Byeong-Hwa,Park, Seung-Kiel,Oh, Sae-Ock,Kim, Young-Geun,Lee, Sang-Do,Kim, Kwang-Jin The Korean Society of Pharmacology 2003 The Korean Journal of Physiology & Pharmacology Vol.7 No.4

Using phospholipase D1 (PLD1)-overexpressing PC12 (PLD1-PC12) cells, the regulatory roles of PLD1 on ATP-induced currents were investigated. In control and PLD1-PC12 cells, ATP increased PLD activity in an external $Ca^{2+}$ dependent manner. PLD activity stimulated by ATP was substantially larger in PLD1-PC12 cells than in control cells. In whole-cell voltage-clamp mode, ATP induced transient inward and outward currents. The outward currents inhibited by TEA or charybdotoxin were significantly larger in PLD1-PC12 cells than in control cells. The inward currents known as $Ca^{2+}$ permeable nonselective cation currents were also larger in PLD1-PC12 cells than in control cells. However, the difference between the two groups of cells disappeared in $Ca^{2+}$-free external solution, where ATP did not activate PLD. Finally, ATP-induced $^{45}Ca$ uptakes were also larger in PLD1-PC12 cells than in control cells. These results suggest that PLD enhances ATP-induced $Ca^{2+}$ influx via $Ca^{2+}$ permeable nonselective cation channels and increases subsequent $Ca^{2+}$-activated $K^+$ currents in PC12 cells.

Role of phospholipase D1 in glucose-induced insulin secretion in pancreatic ${\beta}$ cells

Ma, Wei-Na,Park, Shin-Young,Han, Joong-Soo Korean Society for Biochemistry and Molecular Bion 2010 Experimental and molecular medicine Vol.42 No.6

As glucose is known to induce insulin secretion in pancreatic ${\beta}$ cells, this study investigated the role of a phospholipase D (PLD)-related signaling pathway in insulin secretion caused by high glucose in the pancreatic ${\beta}$-cell line MIN6N8. It was found that the PLD activity and PLD1 expression were both increased by high glucose (33.3 mM) treatment. The dominant negative PLD1 inhibited glucose-induced Beta2 expression, and glucose-induced insulin secretion was blocked by treatment with 1-butanol or PLD1-siRNA. These results suggest that high glucose increased insulin secretion through a PLD1-related pathway. High glucose induced the binding of Arf6 to PLD1. Pretreatment with brefeldin A (BFA), an Arf inhibitor, decreased the PLD activity as well as the insulin secretion. Furthermore, BFA blocked the glucose-induced mTOR and p70S6K activation, while mTOR inhibition with rapamycin attenuated the glucose induced Beta2 expression and insulin secretion. Thus, when taken together, PLD1 would appear to be an important regulator of glucose-induced insulin secretion through an Arf6/PLD1/mTOR/p70S6K/ Beta2 pathway in MIN6N8 cells.

Role of phospholipase D1 in glucose-induced insulin secretion in pancreatic β cells

Wei-na Ma,한중수,Shin-Young Park 생화학분자생물학회 2010 Experimental and molecular medicine Vol.42 No.6

As glucose is known to induce insulin secretion in pancreatic β cells, this study investigated the role of a phospholipase D (PLD)-related signaling pathway in insulin secretion caused by high glucose in the pancreatic β-cell line MIN6N8. It was found that the PLD activity and PLD1 expression were both increased by high glucose (33.3 mM) treatment. The dominant negative PLD1 inhibited glucose-induced Beta2 expression,and glucose-induced insulin secretion was blocked by treatment with 1-butanol or PLD1-siRNA. These results suggest that high glucose increased insulin secretion through a PLD1-related pathway. High glucose induced the binding of Arf6 to PLD1. Pretreatment with brefeldin A (BFA), an Arf inhibitor, decreased the PLD activity as well as the insulin secretion. Furthermore,BFA blocked the glucose-induced mTOR and p70S6K activation, while mTOR inhibition with rapamycin attenuated the glucose induced Beta2 expression and insulin secretion. Thus, when taken together, PLD1would appear to be an important regulator of glucose-induced insulin secretion through an Arf6/PLD1/mTOR/p70S6K/ Beta2 pathway in MIN6N8cells.