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Maekawa S, Yuzu K, Chatani E, Morigaki K. Oligomerization and aggregation of NAP-22 with several metal ions. Neurosci Lett 2024; 821:137623. [PMID: 38184017 DOI: 10.1016/j.neulet.2023.137623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/28/2023] [Accepted: 12/30/2023] [Indexed: 01/08/2024]
Abstract
Metal ions participate in various biochemical processes such as electron transport chain, gene transcription, and enzymatic reactions. Furthermore, the aggregation promoting effect of several metal ions on neuronal proteins such as prion, tau, Aβ peptide, and α-synuclein, has been reported. NAP-22 (also called BASP1 or CAP-23) is a neuron-enriched calmodulin-binding protein and one of the major proteins in the detergent-resistant membrane microdomain fraction of the neuronal cell membrane. Previously, we showed oligomer formation of NAP-22 in the presence of several phospholipids and fatty acids. In this study, we found the aggregation of NAP-22 by FeCl2, FeCl3, and AlCl3 using native-PAGE. Oligomer or aggregate formation of NAP-22 by ZnCl2 or CuSO4 was shown with SDS-PAGE after cross-linking with glutaraldehyde. Morphological analysis with electron microscopy revealed the formation of large aggregates composed of small annular oligomers in the presence of FeCl3, AlCl3, or CuSO4. In case of FeCl2 or ZnCl2, instead of large aggregates, scattered annular and globular oligomers were observed. Interestingly, metal ion induced aggregation of NAP-22 was inhibited by several coenzymes such as NADP+, NADPH, or thiamine pyrophosphate. Since NAP-22 is highly expressed in the presynaptic region of the synapse, this result suggests the participation of metal ions not only on the protein and membrane dynamics at the presynaptic region, but also on the metabolic regulation though the interaction with coenzymes.
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Affiliation(s)
- Shohei Maekawa
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan.
| | - Keisuke Yuzu
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
| | - Eri Chatani
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
| | - Kenichi Morigaki
- Graduate School of Agricultural Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan; Biosignal Research Center, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
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Odagaki SI, Maekawa S, Hayashi F, Suzaki T, Morigaki K. The effects of phospholipids and fatty acids on the oligomer formation of NAP-22. Neurosci Lett 2020; 736:135288. [PMID: 32750402 DOI: 10.1016/j.neulet.2020.135288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/20/2020] [Accepted: 07/30/2020] [Indexed: 10/23/2022]
Abstract
Recovery of various signal transduction molecules in the detergent-resistant membrane microdomain (DRM) fraction suggests the importance of this region in cellular functions. NAP-22 (also called BASP1 or CAP-23) is a neuron-enriched calmodulin-binding protein and one of the major proteins in the DRM fraction of the neuronal cell membrane. Previous studies showed tight binding activity of NAP-22 to acidic membrane lipids and the self-interaction of NAP-22, i.e., oligomerization. In this study, the effect of various phospholipids, lysophospholipids and fatty acids on the oligomerization of NAP-22 was studied through SDS-PAGE after chemical cross-linking and electron microscopic observation. High molecular mass oligomers were detected by SDS-PAGE after incubation in solutions containing over 20 mM NaCl at pH 6.5-8.5, even in the absence of lipid addition, and the addition of Ca2+/calmodulin abolished oligomerization. Higher molecular mass oligomer formation after incubation with acidic phospholipids was detected with gradient SDS-PAGE. Much higher mass oligomers were detected in the presence of polyunsaturated fatty acids. Electron microscopic analysis of the samples after SDS treatment showed tangled rope-like structures. Liposome-bound NAP-22 showed small oval or annular structures after cross-linking and SDS treatment. These oligomers were suggested to make the tangled rope-like structures, for annular structures of the same size were observed in the structure. These results suggest the participation of NAP-22 to liquid-liquid phase separation through oligomerization.
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Affiliation(s)
- Sin-Ichi Odagaki
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
| | - Shohei Maekawa
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan.
| | - Fumio Hayashi
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
| | - Toshinobu Suzaki
- Graduate School of Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
| | - Kenichi Morigaki
- Graduate School of Agricultural Science, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan; Biosignal Research Center, Kobe University, Rokkodaicho 1-1, Nada, Kobe 657-8501, Japan
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Polyphosphoinositides in the nucleus: Roadmap of their effectors and mechanisms of interaction. Adv Biol Regul 2019; 72:7-21. [PMID: 31003946 DOI: 10.1016/j.jbior.2019.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 01/01/2023]
Abstract
Biomolecular interactions between proteins and polyphosphoinositides (PPIn) are essential in the regulation of the vast majority of cellular processes. Consequently, alteration of these interactions is implicated in the development of many diseases. PPIn are phosphorylated derivatives of phosphatidylinositol and consist of seven species with different phosphate combinations. PPIn signal by recruiting proteins via canonical domains or short polybasic motifs. Although their actions are predominantly documented on cytoplasmic membranes, six of the seven PPIn are present within the nucleus together with the PPIn kinases, phosphatases and phospholipases that regulate their turnover. Importantly, the contribution of nuclear PPIn in the regulation of nuclear processes has led to an increased recognition of their importance compared to their more accepted cytoplasmic roles. This review summarises our knowledge on the identification and functional characterisation of nuclear PPIn-effector proteins as well as their mode of interactions, which tend to favour polybasic motifs.
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Maekawa S, Kobayashi Y, Morita M, Suzaki T. Tight binding of NAP-22 with acidic membrane lipids. Neurosci Lett 2015; 600:244-8. [PMID: 26101831 DOI: 10.1016/j.neulet.2015.06.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 05/31/2015] [Accepted: 06/15/2015] [Indexed: 10/23/2022]
Abstract
Recovery of various signal transduction molecules in the detergent-resistant membrane microdomain (DRM) fraction suggests the importance of this region in cellular functions. Insolubility of the outer leaflet of DRM to the non-ionic detergent is ascribed to the tight association of cholesterol and sphingolipid. Since, poor localization of sphingolipid is observed in the inner leaflet, the physicochemical background of the insolubility of the inner leaflet is hence still an enigma. NAP-22 (also called BASP1 or CAP-23) is a neuron-enriched calmodulin-binding protein and one of the major proteins in the DRM of the neuronal cell membrane. A previous study showed the presence of several lipids in a NAP-22 fraction after the process of extraction and column chromatography. In this study, the effect of lipid extraction on NAP-22 was studied through native-gel electrophoresis, ultracentrifugation, and electron microscopic observation. The mobility of NAP-22 in native-PAGE was shifted from low to high after delipidation. Delipidated NAP-22 bound phosphatidylserine (PS), phosphatidylinosotol, and ganglioside. Some part of the mixture of PS and NAP-22 was recovered in the insoluble fraction after Triton X-100 treatment and the addition of cholesterol enhanced the amount of NAP-22 in the insoluble fraction.
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Affiliation(s)
- Shohei Maekawa
- Divison of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan.
| | - Yuumi Kobayashi
- Divison of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Mitsuhiro Morita
- Divison of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
| | - Toshinobu Suzaki
- Divison of Biology, Graduate School of Science, Kobe-University, Kobe 657-8501, Japan
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Kobayashi Y, da Silva R, Kumanogoh H, Miyata S, Sato C, Kitajima K, Nakamura S, Morita M, Hayashi F, Maekawa S. Ganglioside contained in the neuronal tissue-enriched acidic protein of 22 kDa (NAP-22) fraction prepared from the detergent-resistant membrane microdomain of rat brain inhibits the phosphatase activity of calcineurin. J Neurosci Res 2015; 93:1462-70. [PMID: 25981177 DOI: 10.1002/jnr.23599] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 11/05/2022]
Abstract
Neurons have well-developed membrane microdomains called "rafts" that are recovered as a detergent-resistant membrane microdomain fraction (DRM). Neuronal tissue-enriched acidic protein of 22 kDa (NAP-22) is one of the major protein components of neuronal DRM. To determine the cellular function of NAP-22, interacting proteins were screened with an immunoprecipitation assay, and calcineurin (CaN) was detected. Further studies with NAP-22 prepared from DRM and CaN expressed in bacteria showed the binding of these proteins and a dose-dependent inhibitory effect of the NAP-22 fraction on the phosphatase activity of CaN. On the other hand, NAP-22 expressed in bacteria showed low binding to CaN and a weak inhibitory effect on phosphatase activity. To solve this discrepancy, identification of a nonprotein component that modulates CaN activity in the DRM-derived NAP-22 fraction was attempted. After lyophilization, a lipid fraction was extracted with chloroform/methanol. The lipid fraction showed an inhibitory effect on CaN without NAP-22, and further fractionation of the extract with thin-layer chromatography showed the presence of several lipid bands having an inhibitory effect on CaN. The mobility of these bands coincided with that of authentic ganglioside (GM1a, GD1a, GD1b, and GT1b), and authentic ganglioside showed an inhibitory effect on CaN. Treatment of lipid with endoglycoceramidase, which degrades ganglioside to glycochain and ceramide, caused a diminution of the inhibitory effect. These results show that DRM-derived NAP-22 binds several lipids, including ganglioside, and that ganglioside inhibits the phosphatase activity of CaN.
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Affiliation(s)
- Yuumi Kobayashi
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Ronan da Silva
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Haruko Kumanogoh
- Division of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Shinji Miyata
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Chihiro Sato
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Ken Kitajima
- Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan
| | - Shun Nakamura
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Japan
| | - Mistuhiro Morita
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Fumio Hayashi
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
| | - Shohei Maekawa
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
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Maekawa S, Kobayashi Y, Odagaki SI, Makino M, Kumanogoh H, Nakamura S, Morita M, Hayashi F. Interaction of NAP-22 with brain glutamic acid decarboxylase (GAD). Neurosci Lett 2013; 537:50-4. [PMID: 23376695 DOI: 10.1016/j.neulet.2013.01.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 01/07/2013] [Accepted: 01/21/2013] [Indexed: 10/27/2022]
Abstract
NAP-22 (also called BASP1 or CAP-23) is a neuron-enriched protein localized mainly in the synaptic vesicles and the synaptic plasma membrane. Biochemically, it is recovered in the lipid raft fraction. In order to understand the physiological function of the neuronal lipid raft, NAP-22 binding proteins were screened with a pull-down assay. Glutamic acid decarboxylase (GAD) was detected through LC-MS/MS, and Western blotting using a specific antibody confirmed the result. Two isoforms of GAD, GAD65 and GAD67, were expressed in bacteria as GST-fusion forms and the interaction with NAP-22 was confirmed in vitro. Partial co-localization of NAP-22 with GAD65 and GAD67 was also observed in cultured neurons. The binding showed no effect on the enzymatic activity of GAD65 and GAD67. These results hence suggest that NAP-22 could participate in the transport of GAD65 and GAD67 to the presynaptic termini and their retention on the synaptic vesicles as an anchoring protein.
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Affiliation(s)
- Shohei Maekawa
- Department of Biology, Graduate School of Science, Kobe University, Kobe 657-8501, Japan.
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Repression of transcription by WT1-BASP1 requires the myristoylation of BASP1 and the PIP2-dependent recruitment of histone deacetylase. Cell Rep 2012; 2:462-9. [PMID: 22939983 DOI: 10.1016/j.celrep.2012.08.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 07/14/2012] [Accepted: 08/10/2012] [Indexed: 11/20/2022] Open
Abstract
The Wilms' tumor 1 protein WT1 is a transcriptional regulator that is involved in cell growth and differentiation. The transcriptional corepressor BASP1 interacts with WT1 and converts WT1 from a transcriptional activator to a repressor. Here, we demonstrate that the N-terminal myristoylation of BASP1 is required in order to elicit transcriptional repression at WT1 target genes. We show that myristoylated BASP1 binds to nuclear PIP2, which leads to the recruitment of PIP2 to the promoter regions of WT1-dependent target genes. BASP1's myristoylation and association with PIP2 are required for the interaction of BASP1 with HDAC1, which mediates the recruitment of HDAC1 to the promoter and elicits transcriptional repression. Our findings uncover a role for myristoylation in transcription, as well as a critical function for PIP2 in gene-specific transcriptional repression through the recruitment of histone deacetylase.
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Takaichi R, Odagaki SI, Kumanogoh H, Nakamura S, Morita M, Maekawa S. Inhibitory effect of NAP-22 on the phosphatase activity of synaptojanin-1. J Neurosci Res 2011; 90:21-7. [DOI: 10.1002/jnr.22740] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 05/27/2011] [Accepted: 06/20/2011] [Indexed: 01/28/2023]
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Oligomeric structure of brain abundant proteins GAP-43 and BASP1. J Struct Biol 2010; 170:470-83. [PMID: 20109554 DOI: 10.1016/j.jsb.2010.01.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/21/2009] [Accepted: 01/20/2010] [Indexed: 11/19/2022]
Abstract
Brain abundant proteins GAP-43 and BASP1 participate in the regulation of actin cytoskeleton dynamics in neuronal axon terminals. The proposed mechanism suggests that the proteins sequester phosphatidylinositol-4,5-diphosphate (PIP(2)) in the inner leaflet of the plasma membrane. We found that model anionic phospholipid membranes in the form of liposomes induce rapid oligomerization of GAP-43 and BASP1 proteins. Multiply charged phosphoinositides produced the most potent effect. Anionic detergent sodium dodecyl sulfate (SDS) at submicellar concentration stimulated formation of similar oligomers in solution. BASP1, but not GAP-43, also formed oligomers at sufficiently high concentration in the absence of lipids and SDS. Electron microscopy study demonstrated that the oligomers have disk-shaped or annular structure of 10-30nm in diameter. BASP1 also formed higher aggregates of linear rod-like structure, with average length of about 100nm. In outward appearance, the oligomers and linear aggregates are reminiscent of oligomers and protofibrils of amyloid proteins. Both the synthetic N-terminal peptide GAP-43(1-40) and the brain-derived fragment GAP-43-3 preserved the ability to oligomerize under the action of acidic phospholipids and SDS. On the contrary, BASP1 fragment truncated by the short N-terminal myristoylated peptide was unable to form oligomers. GAP-43 and BASP1 oligomerization can be regulated by calmodulin, which disrupts the oligomers and displaces the proteins from the membrane. We suggest that in vivo, the role of membrane-bound GAP-43 and BASP1 oligomers consists in accumulation of PIP(2) in functional clusters, which become accessible for other PIP(2)-binding proteins after dissociation of the oligomers.
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Abstract
Up to now less than a handful of viral cholesterol-binding proteins have been characterized, in HIV, influenza virus and Semliki Forest virus. These are proteins with roles in virus entry or morphogenesis. In the case of the HIV fusion protein gp41 cholesterol binding is attributed to a cholesterol recognition consensus (CRAC) motif in a flexible domain of the ectodomain preceding the trans-membrane segment. This specific CRAC sequence mediates gp41 binding to a cholesterol affinity column. Mutations in this motif arrest virus fusion at the hemifusion stage and modify the ability of the isolated CRAC peptide to induce segregation of cholesterol in artificial membranes.Influenza A virus M2 protein co-purifies with cholesterol. Its proton translocation activity, responsible for virus uncoating, is not cholesterol-dependent, and the transmembrane channel appears too short for integral raft insertion. Cholesterol binding may be mediated by CRAC motifs in the flexible post-TM domain, which harbours three determinants of binding to membrane rafts. Mutation of the CRAC motif of the WSN strain attenuates virulence for mice. Its affinity to the raft-non-raft interface is predicted to target M2 protein to the periphery of lipid raft microdomains, the sites of virus assembly. Its influence on the morphology of budding virus implicates M2 as factor in virus fission at the raft boundary. Moreover, M2 is an essential factor in sorting the segmented genome into virus particles, indicating that M2 also has a role in priming the outgrowth of virus buds.SFV E1 protein is the first viral type-II fusion protein demonstrated to directly bind cholesterol when the fusion peptide loop locks into the target membrane. Cholesterol binding is modulated by another, proximal loop, which is also important during virus budding and as a host range determinant, as shown by mutational studies.
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Affiliation(s)
- Cornelia Schroeder
- Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, D-01307, Dresden, Germany.
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Ohno-Iwashita Y, Shimada Y, Hayashi M, Iwamoto M, Iwashita S, Inomata M. Cholesterol-binding toxins and anti-cholesterol antibodies as structural probes for cholesterol localization. Subcell Biochem 2010; 51:597-621. [PMID: 20213560 DOI: 10.1007/978-90-481-8622-8_22] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Cholesterol is one of the major constituents of mammalian cell membranes. It plays an indispensable role in regulating the structure and function of cell membranes and affects the pathology of various diseases. In recent decades much attention has been paid to the existence of membrane microdomains, generally termed lipid "rafts", and cholesterol, along with sphingolipids, is thought to play a critical role in raft structural organization and function. Cholesterol-binding probes are likely to provide useful tools for analyzing the distribution and dynamics of membrane cholesterol, as a structural element of raft microdomains, and elsewhere within the cell. Among the probes, non-toxic derivatives of perfringolysin O, a cholesterol-binding cytolysin, bind cholesterol in a concentration-dependent fashion with a strict threshold. They selectively recognize cholesterol in cholesterol-enriched membranes, and have been used in many studies to detect microdomains in plasma and intracellular membranes. Anti-cholesterol antibodies that recognize cholesterol in domain structures have been developed in recent years. In this chapter, we describe the characteristics of these cholesterol-binding proteins and their applications to studies on membrane cholesterol localization.
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Affiliation(s)
- Yoshiko Ohno-Iwashita
- Faculty of Pharmacy, Iwaki Meisei University, 5-5-1 Chuodai Iino, Iwaki City, Fukushima, 970-8551, Japan.
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Odagaki SI, Kumanogoh H, Nakamura S, Maekawa S. Biochemical interaction of an actin-capping protein, CapZ, with NAP-22. J Neurosci Res 2009; 87:1980-5. [DOI: 10.1002/jnr.22040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Maimaitiyiming M, Kumanogoh H, Nakamura S, Nagata KI, Suzaki T, Maekawa S. Biochemical characterization of membrane-associated septin from rat brain. J Neurochem 2008; 106:1175-83. [DOI: 10.1111/j.1471-4159.2008.05450.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tsuda R, Kumanogoh H, Umeda M, Maekawa S. Morphological analysis on the distribution of membrane lipids and a membrane protein, NAP-22, during neuronal development in vitro. J Mol Histol 2008; 39:371-9. [DOI: 10.1007/s10735-008-9175-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 05/27/2008] [Indexed: 11/24/2022]
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Ohno-Iwashita Y, Shimada Y, Waheed AA, Hayashi M, Inomata M, Nakamura M, Maruya M, Iwashita S. Perfringolysin O, a cholesterol-binding cytolysin, as a probe for lipid rafts. Anaerobe 2007; 10:125-34. [PMID: 16701509 DOI: 10.1016/j.anaerobe.2003.09.003] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2003] [Revised: 06/29/2003] [Accepted: 09/19/2003] [Indexed: 12/20/2022]
Abstract
Gaining an understanding of the structural and functional roles of cholesterol in membrane lipid rafts is a critical issue in studies on cellular signaling and because of the possible involvement of lipid rafts in various diseases. We have focused on the potential of perfringolysin O (theta-toxin), a cholesterol-binding cytolysin produced by Clostridium perfringens, as a probe for studies on membrane cholesterol. We prepared a protease-nicked and biotinylated derivative of perfringolysin O (BCtheta) that binds selectively to cholesterol in cholesterol-rich microdomains of cell membranes without causing membrane lesions. Since the domains fulfill the criteria of lipid rafts, BCtheta can be used to detect cholesterol-rich lipid rafts. This is in marked contrast to filipin, another cholesterol-binding reagent, which binds indiscriminately to cell cholesterol. Using BCtheta, we are now searching for molecules that localize specifically in cholesterol-rich lipid rafts. Recently, we demonstrated that the C-terminal domain of perfringolysin O, domain 4 (D4), possesses the same binding characteristics as BCtheta. BIAcore analysis showed that D4 binds specifically to cholesterol with the same binding affinity as the full-size toxin. Cell-bound D4 is recovered predominantly from detergent-insoluble, low-density membrane fractions where raft markers, such as cholesterol, flotillin and Src family kinases, are enriched, indicating that D4 also binds selectively to lipid rafts. Furthermore, a green fluorescent protein-D4 fusion protein (GFP-D4) was revealed to be useful for real-time monitoring of cholesterol in lipid rafts in the plasma membrane. In addition, the expression of GFP-D4 in the cytoplasm might allow the investigations of intracellular trafficking of lipid rafts. The simultaneous visualization of lipid rafts in plasma membranes and inside cells might help in gaining a total understanding of the dynamic behavior of lipid rafts.
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Affiliation(s)
- Yoshiko Ohno-Iwashita
- Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, Japan.
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Taguchi K, Kumanogoh H, Nakamura S, Maekawa S. Localization of phospholipase Cβ1 on the detergent-resistant membrane microdomain prepared from the synaptic plasma membrane fraction of rat brain. J Neurosci Res 2007; 85:1364-71. [PMID: 17348042 DOI: 10.1002/jnr.21243] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The membrane microdomain (MD), such as detergent-resistant low-density membrane microdomain fraction (DRM), has been paid much attention because many signal-transducing molecules are recovered in this fraction, although precise localization and interactions of these molecules are largely unclear. To identify neuronal MD-localized proteins, monoclonal antibodies (mAbs) against the DRM-components of synaptic plasma membrane fraction (SPM) were produced and the antigens were characterized. One of the antigens reacted with two closely positioned bands of about 140 kDa in SDS-PAGE and the antigen showed age-dependent localization on DRM. The antigen was immunoprecipitated with the mAb after partial solubilization with 0.6 M NaCl from SPM-derived DRM and identified as phospholipase C beta 1 through mass analysis. The identity was further confirmed with Western blotting using a specific polyclonal antibody. The enzyme purified from the DRM was activated by the alpha subunit of trimeric G protein, Gq, expressed in HEK293 cells. The lipid composition of the liposomes affected the enzymatic activity and the addition of NAP-22, a neuronal DRM-localized protein, inhibited the activity. These results suggest that there exists a signal-transducing MD that performs important roles in neuronal functions through PIP(2) signaling and Ca(2+) mobilization.
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Affiliation(s)
- Katsutoshi Taguchi
- Division of Bioinformation, Department of Biosystems Science, Graduate School of Science and Technology, Kobe-University, Kobe, Japan
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Selvakumar P, Lakshmikuttyamma A, Shrivastav A, Das SB, Dimmock JR, Sharma RK. Potential role of N-myristoyltransferase in cancer. Prog Lipid Res 2007; 46:1-36. [PMID: 16846646 DOI: 10.1016/j.plipres.2006.05.002] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Colorectal cancer is the second leading cause of malignant death, and better preventive strategies are needed. The treatment of colonic cancer remains difficult because of the lack of effective chemotherapeutic agents; therefore it is important to continue to search for cellular functions that can be disrupted by chemotherapeutic drugs resulting in the inhibition of the development and progression of cancer. The current knowledge of the modification of proteins by myristoylation involving myristoyl-CoA: protein N-myristoyltransferase (NMT) is in its infancy. This process is involved in the pathogenesis of cancer. We have reported for the first time that NMT activity and protein expression were higher in human colorectal cancer, gallbladder carcinoma and brain tumors. In addition, an increase in NMT activity appeared at an early stage in colonic carcinogenesis. It is conceivable therefore that NMT can be used as a potential marker for the early detection of cancer. These observations lead to the possibility of developing NMT specific inhibitors, which may be therapeutically useful. We proposed that HSC70 and/or enolase could be used as an anticancer therapeutic target. This review summarized the status of NMT in cancer which has been carried in our laboratory.
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Affiliation(s)
- Ponniah Selvakumar
- Department of Pathology and Laboratory Medicine, College of Medicine, and Health Research Division, Saskatchewan Cancer Agency, University of Saskatchewan, 20 Campus Drive, Saskatoon, Sask., Canada S7N 4H4
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18
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Mima J, Fukada H, Nagayama M, Ueda M. Specific membrane binding of the carboxypeptidase Y inhibitor I(C), a phosphatidylethanolamine-binding protein family member. FEBS J 2006; 273:5374-83. [PMID: 17076703 DOI: 10.1111/j.1742-4658.2006.05530.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
I(C), an endogenous cytoplasmic inhibitor of vacuolar carboxypeptidase Y in the yeast Saccharomyces cerevisiae, is classified as a member of the phosphatidylethanolamine-binding protein family. The binding of I(C) to phospholipid membranes was first analyzed using a liposome-binding assay and by surface plasmon resonance measurements, which revealed that the affinity of this inhibitor was not for phosphatidylethanolamine but for anionic phospholipids, such as phosphatidylserine, phosphatidylinositol 3-phosphate, phosphatidylinositol 3,4-bisphosphate, and phosphatidylinositol 3,4,5-trisphosphate, with K(D) values below 100 nm. The liposome-binding assay and surface plasmon resonance analyses of I(C), when complexed with carboxypeptidase Y, and the mutant forms of I(C) further suggest that the N-terminal segment (Met1-His18) in its carboxypeptidase Y-binding sites is involved in the specific and efficient binding to anionic phospholipid membranes. The binding of I(C) to cellular membranes was subsequently analyzed by fluorescence microscopy of yeast cells producing the green fluorescent protein-tagged I(C), suggesting that I(C) is specifically targeted to vacuolar membranes rather than cytoplasmic membranes, during the stationary growth phase. The present findings provide novel insights into the membrane-targeting and biological functions of I(C) and phosphatidylethanolamine-binding proteins.
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Affiliation(s)
- Joji Mima
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Japan.
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19
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Epand RF, Sayer BG, Epand RM. Induction of raft-like domains by a myristoylated NAP-22 peptide and its Tyr mutant. FEBS J 2005; 272:1792-803. [PMID: 15794765 DOI: 10.1111/j.1742-4658.2005.04612.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The N-terminally myristoylated, 19-amino acid peptide, corresponding to the amino terminus of the neuronal protein NAP-22 (NAP-22 peptide) is a naturally occurring peptide that had been shown by fluorescence to cause the sequestering of a Bodipy-labeled PtdIns(4,5)P2 in a cholesterol-dependent manner. The present work, using differential scanning calorimetry (DSC), extends the observation that formation of a PtdIns(4,5)P2-rich domain is cholesterol dependent and shows that it also leads to the formation of a cholesterol-depleted domain. The PtdIns(4,5)P2 used in the present work is extracted from natural sources and does not contain any label and has the native acyl chain composition. Peptide-induced formation of a cholesterol-depleted domain is abolished when the sole aromatic amino acid, Tyr11 is replaced with a Leu. Despite this, the modified peptide can still sequester PtdIns(4,5)P2 into domains, probably because of the presence of a cluster of cationic residues in the peptide. Cholesterol and PtdIns(4,5)P2 also modulate the insertion of the peptide into the bilayer as revealed by 1H NOESY MAS/NMR. The intensity of cross peaks between the aromatic protons of the Tyr residue and the protons of the lipid indicate that in the presence of cholesterol there is a change in the nature of the interaction of the peptide with the membrane. These results have important implications for the mechanism by which NAP-22 affects actin reorganization in neurons.
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Affiliation(s)
- Raquel F Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON Canada.
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20
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Epand RM. Do proteins facilitate the formation of cholesterol-rich domains? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2005; 1666:227-38. [PMID: 15519317 DOI: 10.1016/j.bbamem.2004.07.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2004] [Revised: 07/21/2004] [Accepted: 07/23/2004] [Indexed: 01/10/2023]
Abstract
Both biological and model membranes can exhibit the formation of domains. A brief review of some of the diverse methodologies used to identify the presence of domains in membranes is given. Some of these domains are enriched in cholesterol. The segregation of lipids into cholesterol-rich domains can occur in both pure lipid systems as well as membranes containing peptides and proteins. Peptides and proteins can promote the formation of cholesterol-rich domains not only by preferentially interacting with cholesterol and being sequestered into these regions of the membrane, but also indirectly as a consequence of being excluded from cholesterol-rich domains. The redistribution of components is dictated by the thermodynamics of the system. The formation of domains in a biological membrane is a consequence of all of the intermolecular interactions including those among lipid molecules as well as between lipids and proteins.
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Affiliation(s)
- Richard M Epand
- Department of Biochemistry, McMaster University Hamilton, ON L8N 3Z5, Canada.
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21
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Mosevitsky MI. Nerve Ending “Signal” Proteins GAP‐43, MARCKS, and BASP1. INTERNATIONAL REVIEW OF CYTOLOGY 2005; 245:245-325. [PMID: 16125549 DOI: 10.1016/s0074-7696(05)45007-x] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Mechanisms of growth cone pathfinding in the course of neuronal net formation as well as mechanisms of learning and memory have been under intense investigation for the past 20 years, but many aspects of these phenomena remain unresolved and even mysterious. "Signal" proteins accumulated mainly in the axon endings (growth cones and the presynaptic area of synapses) participate in the main brain processes. These proteins are similar in several essential structural and functional properties. The most prominent similarities are N-terminal fatty acylation and the presence of an "effector domain" (ED) that dynamically binds to the plasma membrane, to calmodulin, and to actin fibrils. Reversible phosphorylation of ED by protein kinase C modulates these interactions. However, together with similarities, there are significant differences among the proteins, such as different conditions (Ca2+ contents) for calmodulin binding and different modes of interaction with the actin cytoskeleton. In light of these facts, we consider GAP-43, MARCKS, and BASP1 both separately and in conjunction. Special attention is devoted to a discussion of apparent inconsistencies in results and opinions of different authors concerning specific questions about the structure of proteins and their interactions.
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Affiliation(s)
- Mark I Mosevitsky
- Division of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute, Russian Academy of Sciences, 188300 Gatchina Leningrad District, Russian Federation
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22
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Nöllmann M, Gilbert R, Mitchell T, Sferrazza M, Byron O. The role of cholesterol in the activity of pneumolysin, a bacterial protein toxin. Biophys J 2004; 86:3141-51. [PMID: 15111427 PMCID: PMC1304179 DOI: 10.1016/s0006-3495(04)74362-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The mechanism via which pneumolysin (PLY), a toxin and major virulence factor of the bacterium Streptococcus pneumoniae, binds to its putative receptor, cholesterol, is still poorly understood. We present results from a series of biophysical studies that shed light on the interaction of PLY with cholesterol in solution and in lipid bilayers. PLY lyses cells whose walls contain cholesterol. Using standard hemolytic assays we have demonstrated that the hemolytic activity of PLY is inhibited by cholesterol, partially by ergosterol but not by lanosterol and that the functional stoichiometry of the cholesterol-PLY complex is 1:1. Tryptophan (Trp) fluorescence data recorded during PLY-cholesterol titration studies confirm this ratio, reveal a significant blue shift in the Trp fluorescence peak with increasing cholesterol concentrations indicative of increasing nonpolarity in the Trp environment, consistent with cholesterol binding by the tryptophans, and provide a measure of the affinity of cholesterol binding: K(d) = 400 +/- 100 nM. Finally, we have performed specular neutron reflectivity studies to observe the effect of PLY upon lipid bilayer structure.
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Affiliation(s)
- Marcelo Nöllmann
- Division of Infection and Immunity, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
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23
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24
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Lucero HA, Robbins PW. Lipid rafts-protein association and the regulation of protein activity. Arch Biochem Biophys 2004; 426:208-24. [PMID: 15158671 DOI: 10.1016/j.abb.2004.03.020] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2004] [Revised: 03/22/2004] [Indexed: 11/18/2022]
Abstract
Lipid rafts are membrane microdomains enriched in saturated phospholipids, sphingolipids, and cholesterol. They have a varied but distinct protein composition and have been implicated in diverse cellular processes including polarized traffic, signal transduction, endo- and exo-cytoses, entrance of obligate intracellular pathogens, and generation of pathological forms of proteins associated with Alzheimer's and prion diseases. Raft proteins can be permanently or temporarily associated to lipid rafts. Here, we review recent advances on the biochemical and cell biological characterization of rafts, and on the emerging concept of the temporary residency of proteins in rafts as a regulatory mechanism of their biological activity.
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Affiliation(s)
- Héctor A Lucero
- Department of Molecular and Cell Biology, Goldman School of Dental Medicine, Boston University Medical Center, Boston, MA 02118, USA.
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25
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Iino S, Taguchi K, Maekawa S, Nojyo Y. Motor, sensory and autonomic nerve terminals containing NAP-22 immunoreactivity in the rat muscle. Brain Res 2004; 1002:142-50. [PMID: 14988044 DOI: 10.1016/j.brainres.2004.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2004] [Indexed: 10/26/2022]
Abstract
Neuron-enriched acidic protein having a molecular mass of 22 kDa, NAP-22, is a Ca(2+)-dependent calmodulin-binding protein and is phosphorylated with protein kinase C (PKC). This protein is localized to the biological membrane via myristoylation and found in the membrane fraction of the brain and in the synaptic vesicle fraction. Recent studies showed that NAP-22 is localized in the membrane raft domain in a cholesterol-dependent manner and suggest a role for NAP-22 in maturation and/or maintenance of nerve terminals by controlling cholesterol-dependent membrane dynamics. The present study revealed the immunohistochemical distribution of NAP-22 in the peripheral nerves in rat muscles. In all examined muscles, nerve terminals in the motor endplates showed NAP-22 immunoreactivity associated with the membranes of synaptic vesicles and nerve terminals. In the muscle spindles, annulospiral endings, which made spirals around the intrafusal muscles, showed intense NAP-22 immunoreactivity. Autonomic nerve fibers around the intramuscular blood vessels also showed the immunoreactivity for NAP-22. NAP-22 immunoreactivity in these peripheral nerves was observed from birth to adulthood (100 days after birth). Though growth-associated protein-43 (GAP-43) immunoreactivity in these nerves was observed from birth, this immunoreactivity decreased from 20 days after birth. These findings suggest that NAP-22 is distributed and regulates functions in the motor, sensory and autonomic nerve terminals in the peripheral nervous system.
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Affiliation(s)
- Satoshi Iino
- Department of Anatomy, University of Fukui Faculty of Medical Science, Matsuoka, Fukui 910-1193, Japan.
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26
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Maurer-Stroh S, Gouda M, Novatchkova M, Schleiffer A, Schneider G, Sirota FL, Wildpaner M, Hayashi N, Eisenhaber F. MYRbase: analysis of genome-wide glycine myristoylation enlarges the functional spectrum of eukaryotic myristoylated proteins. Genome Biol 2004; 5:R21. [PMID: 15003124 PMCID: PMC395771 DOI: 10.1186/gb-2004-5-3-r21] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Revised: 12/17/2003] [Accepted: 01/08/2004] [Indexed: 11/25/2022] Open
Abstract
We evaluated the evolutionary conservation of glycine myristoylation within eukaryotic sequences. Our large-scale cross-genome analyses, available as MYRbase, show that the functional spectrum of myristoylated proteins is currently largely underestimated. We give experimental evidence for in vitro myristoylation of selected predictions. Furthermore, we classify five membrane-attachment factors that occur most frequently in combination with, or even replacing, myristoyl anchors, as some protein family examples show.
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Affiliation(s)
- Sebastian Maurer-Stroh
- IMP Research Institute of Molecular Pathology, Dr, Bohr-Gasse 7, A-1030 Vienna, Austria.
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27
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Epand RM, Braswell EH, Yip CM, Epand RF, Maekawa S. Quaternary structure of the neuronal protein NAP-22 in aqueous solution. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1650:50-8. [PMID: 12922169 DOI: 10.1016/s1570-9639(03)00191-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
NAP-22, a myristoylated, anionic protein, is a major protein component of the detergent-insoluble fraction of neurons. After extraction from the membrane, it is readily soluble in water. NAP-22 will partition only into membranes with specific lipid compositions. The lipid specificity is not expected for a monomeric myristoylated protein. We have studied the self-association of NAP-22 in solution. Sedimentation velocity experiments indicated that the protein is largely associated. The low concentration limiting s value is approximately 1.3 S, indicating a highly asymmetric monomer. In contrast, a nonmyristoylated form of the protein shows no evidence of oligomerization by velocity sedimentation and has an s value corresponding to the smallest component of NAP-22, but without the presence of higher oligomers. Sedimentation equilibrium runs indicate that there is a rapidly reversible equilibrium between monomeric and oligomeric forms of the protein followed by a slower, more irreversible association into larger aggregates. In situ atomic force microscopy of the protein deposited on mica from freshly prepared dilute solution revealed dimers on the mica surface. The values of the association constants obtained from the sedimentation equilibrium data suggest that the weight concentration of the monomer exceeds that of the dimer below a total protein concentration of 0.04 mg/ml. Since the concentration of NAP-22 in the neurons of the developing brain is approximately 0.6 mg/ml, if the protein were in solution, it would be in oligomeric form and bind specifically to cholesterol-rich domains. We demonstrate, using fluorescence resonance energy transfer, that at low concentrations, NAP-22 labeled with Texas Red binds equally well to liposomes of phosphatidylcholine either with or without the addition of 40 mol% cholesterol. Thus, oligomerization of NAP-22 contributes to its lipid selectivity during membrane binding.
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Affiliation(s)
- Richard M Epand
- Health Sciences Center, Department of Biochemistry, McMaster University, 1200 Main Street West, Hamilton, ON, Canada L8N 3Z5.
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28
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Khan TK, Yang B, Thompson NL, Maekawa S, Epand RM, Jacobson K. Binding of NAP-22, a calmodulin-binding neuronal protein, to raft-like domains in model membranes. Biochemistry 2003; 42:4780-6. [PMID: 12718518 DOI: 10.1021/bi0265877] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cholesterol-binding protein NAP-22 is a major component of the detergent-insoluble low-density fraction of rat brain. In this study, we found, using fluorescence microscopy, that native NAP-22, but not a demyristoylated form, binds to cholesterol-rich raft-like domains in planar-supported monolayers and remains bound after nonionic detergent extraction. NAP-22 also protects the cholesterol-rich domains during extraction by methyl-beta-cyclodextrin. The lateral mobility of this protein is much lower than that of other raft components in model membranes, suggesting that both cholesterol binding and inter-NAP-22 interactions markedly reduce its lateral diffusion. This study suggests that NAP-22 binding may be employed to image cholesterol-rich regions, such as caveolae/rafts, on the plasma membrane of cells, and preliminary efforts in that direction are presented.
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Affiliation(s)
- Tapan K Khan
- Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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29
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Maekawa S, Iino S, Miyata S. Molecular characterization of the detergent-insoluble cholesterol-rich membrane microdomain (raft) of the central nervous system. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1610:261-70. [PMID: 12648779 DOI: 10.1016/s0005-2736(03)00023-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Many fundamental neurological issues such as neuronal polarity, the formation and remodeling of synapses, synaptic transmission, and the pathogenesis of the neuronal cell death are closely related to the membrane dynamics. The elucidation of functional roles of a detergent-insoluble cholesterol-rich domain (raft) could therefore provide good clues to the molecular understanding of these important phenomena, for the participation of the raft in the fundamental cell functions, such as signal transduction and selective transport of lipids and proteins, has been elucidated in nonneural cells. Interestingly, the brain is rich in raft and the brain-derived raft differs in its lipid and protein components from other tissue-derived rafts. Since many excellent reviews are written on the membrane lipid dynamics of this microdomain, signal transduction, and neuronal glycolipids, we review on the characterization of the raft proteins recovered in the detergent-insoluble low-density fraction from rat brain. Special focus is addressed on the biochemical characterization of a neuronal enriched protein, NAP-22, for the lipid organizing activity of this protein has become increasingly clear.
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Affiliation(s)
- Shohei Maekawa
- Department of Life Science, Graduate School of Science and Technology, Kobe University, Rokkodai 1-1, Kobe 657-8501, Japan.
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