Abstract
The scaffold protein alpha-syntrophin (SNTA) is a component of the dystrophin glycoprotein complex and has been comprehensively studied in skeletal muscle and adipocytes. SNTA is further expressed in the liver where its biological role remains unclear. Unpublished data from our group suggested that SNTA deficiency is associated with altered tubulin alpha 8 (TUBA8) levels in fat. TUBA8 is highly expressed in different cell lines including hepatoma cells, and here we analyzed whether SNTA has a role herein. In Hepa1-6 cells, TUBA8 protein levels were increased upon SNTA knock down and were reduced upon overexpression of SNTA. This regulation was not identified when analyzing mRNA expression. In the liver of SNTA-deficient mice, TUBA8 protein was higher compared to the respective wild-type controls while RNA expression was even suppressed. Using the HaloTag platform, TUBA8 was found to form a complex with SNTA in Hepa1-6 cells. In the hepatic stellate cell line LX-2, the lack or overexpression of SNTA did, however, not change TUBA8 protein expression. SNTA and TUBA8 are described to regulate cell proliferation. Yet, knock down of SNTA did neither affect proliferation nor viability of Hepa1-6 cells. The present study shows that SNTA protein levels are inversely related to TUBA8 protein expression in the hepatocyte cell line Hepa1-6.
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Abdollahi MR, Morrison E, Sirey T, Molnar Z, Hayward BE, Carr IM, Springell K, Woods CG, Ahmed M, Hattingh L, Corry P, Pilz DT, Stoodley N, Crow Y, Taylor GR, Bonthron DT, Sheridan E (2009) Mutation of the variant alpha-tubulin TUBA8 results in polymicrogyria with optic nerve hypoplasia. Am J Hum Genet 85:737–744. https://doi.org/10.1016/j.ajhg.2009.10.007
Adams ME, Mueller HA, Froehner SC (2001) In vivo requirement of the alpha-syntrophin PDZ domain for the sarcolemmal localization of nNOS and aquaporin-4. J Cell Biol 155:113–122. https://doi.org/10.1083/jcb.200106158
Adams ME, Kramarcy N, Fukuda T, Engel AG, Sealock R, Froehner SC (2004) Structural abnormalities at neuromuscular synapses lacking multiple syntrophin isoforms. J Neurosci 24:10302–10309
Aquilano K, Baldelli S, Ciriolo MR (2014) Nuclear recruitment of neuronal nitric-oxide synthase by alpha-syntrophin is crucial for the induction of mitochondrial biogenesis. J Biol Chem 289:365–378. https://doi.org/10.1074/jbc.M113.506733
Arcondeguy T, Lacazette E, Millevoi S, Prats H, Touriol C (2013) VEGF-A mRNA processing, stability and translation: a paradigm for intricate regulation of gene expression at the post-transcriptional level. Nucleic Acids Res 41:7997–8010. https://doi.org/10.1093/nar/gkt539
Baffy G, Brunt EM, Caldwell SH (2012) Hepatocellular carcinoma in non-alcoholic fatty liver disease: an emerging menace. J Hepatol 56:1384–1391. https://doi.org/10.1016/j.jhep.2011.10.027
Bauer S, Wanninger J, Schmidhofer S, Weigert J, Neumeier M, Dorn C, Hellerbrand C, Zimara N, Schaffler A, Aslanidis C, Buechler C (2011) Sterol regulatory element-binding protein 2 (SREBP2) activation after excess triglyceride storage induces chemerin in hypertrophic adipocytes. Endocrinology 152:26–35. https://doi.org/10.1210/en.2010-1157
Belvindrah R, Natarajan K, Shabajee P, Bruel-Jungerman E, Bernard J, Goutierre M, Moutkine I, Jaglin XH, Savariradjane M, Irinopoulou T, Poncer JC, Janke C, Francis F (2017) Mutation of the alpha-tubulin Tuba1a leads to straighter microtubules and perturbs neuronal migration. J Cell Biol 216:2443–2461. https://doi.org/10.1083/jcb.201607074
Bhat HF, Adams ME, Khanday FA (2013) Syntrophin proteins as Santa Claus: role(s) in cell signal transduction. Cell Mol Life Sci 70:2533–2554. https://doi.org/10.1007/s00018-012-1233-9
Bhat HF, Baba RA, Adams ME, Khanday FA (2014) Role of SNTA1 in Rac1 activation, modulation of ROS generation, and migratory potential of human breast cancer cells. Br J Cancer 110:706–714. https://doi.org/10.1038/bjc.2013.723
Boutari C, Perakakis N, Mantzoros CS (2018) Association of adipokines with development and progression of nonalcoholic fatty liver disease. Endocrinol Metab (Seoul) 33:33–43. https://doi.org/10.3803/EnM.2018.33.1.33
Buechler C, Wanninger J, Neumeier M (2011) Adiponectin, a key adipokine in obesity related liver diseases. World J Gastroenterol 17:2801–2811. https://doi.org/10.3748/wjg.v17.i23.2801
Cowherd RM, Lyle RE, McGehee RE Jr (1999) Molecular regulation of adipocyte differentiation. Semin Cell Dev Biol 10:3–10
Eisinger K, Rein-Fischboeck L, Pohl R, Meier EM, Krautbauer S, Buechler C (2016) The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth. Exp Cell Res 345:100–107. https://doi.org/10.1016/j.yexcr.2016.05.020
Eisinger K, Rein-Fischboeck L, Neumeier M, Schmidhofer S, Pohl R, Haberl EM, Liebisch G, Kopp A, Schmid A, Krautbauer S, Buechler C (2018) Alpha-syntrophin deficient mice are protected from adipocyte hypertrophy and ectopic triglyceride deposition in obesity. Exp Mol Pathol 104:212–221. https://doi.org/10.1016/j.yexmp.2018.04.003
Fuhrmann-Stroissnigg H, Noiges R, Descovich L, Fischer I, Albrecht DE, Nothias F, Froehner SC, Propst F (2012) The light chains of microtubule-associated proteins MAP1A and MAP1B interact with alpha1-syntrophin in the central and peripheral nervous system. PLoS One 7:e49722. https://doi.org/10.1371/journal.pone.0049722
Gorovoy M, Niu J, Bernard O, Profirovic J, Minshall R, Neamu R, Voyno-Yasenetskaya T (2005) LIM kinase 1 coordinates microtubule stability and actin polymerization in human endothelial cells. J Biol Chem 280:26533–26542. https://doi.org/10.1074/jbc.M502921200
Halpain S, Dehmelt L (2006) The MAP1 family of microtubule-associated proteins. Genome Biol 7:224
Hebel T, Eisinger K, Neumeier M, Rein-Fischboeck L, Pohl R, Meier EM, Boettcher A, Froehner SC, Adams ME, Liebisch G, Krautbauer S, Buechler C (2015) Lipid abnormalities in alpha/beta2-syntrophin null mice are independent from ABCA1. Biochim Biophys Acta 1851:527–536. https://doi.org/10.1016/j.bbalip.2015.01.012
Hogan A, Yakubchyk Y, Chabot J, Obagi C, Daher E, Maekawa K, Gee SH (2004) The phosphoinositol 3,4-bisphosphate-binding protein TAPP1 interacts with syntrophins and regulates actin cytoskeletal organization. J Biol Chem 279:53717–53724. https://doi.org/10.1074/jbc.M410654200
Iwata Y, Sampaolesi M, Shigekawa M, Wakabayashi S (2004) Syntrophin is an actin-binding protein the cellular localization of which is regulated through cytoskeletal reorganization in skeletal muscle cells. Eur J Cell Biol 83:555–565
Kamino H, Moore R, Negishi M (2011) Role of a novel CAR-induced gene, TUBA8, in hepatocellular carcinoma cell lines. Cancer Genet 204:382–391. https://doi.org/10.1016/j.cancergen.2011.05.007
Kirkin V, McEwan DG, Novak I, Dikic I (2009) A role for ubiquitin in selective autophagy. Mol Cell 34:259–269. https://doi.org/10.1016/j.molcel.2009.04.026
Luo S, Chen Y, Lai KO, Arevalo JC, Froehner SC, Adams ME, Chao MV, Ip NY (2005) {alpha}-Syntrophin regulates ARMS localization at the neuromuscular junction and enhances EphA4 signaling in an ARMS-dependent manner. J Cell Biol 169:813–824. https://doi.org/10.1083/jcb.200412008
Moon JY, Choi SJ, Heo CH, Kim HM, Kim HS (2017) Alpha-syntrophin stabilizes catalase to reduce endogenous reactive oxygen species levels during myoblast differentiation. FEBS J 284:2052–2065. https://doi.org/10.1111/febs.14103
Munehira Y, Ohnishi T, Kawamoto S, Furuya A, Shitara K, Imamura M, Yokota T, Takeda S, Amachi T, Matsuo M, Kioka N, Ueda K (2004) Alpha1-syntrophin modulates turnover of ABCA1. J Biol Chem 279:15091–15095. https://doi.org/10.1074/jbc.M313436200
Rein-Fischboeck L, Pohl R, Haberl EM, Weiss TS, Buechler C (2017) The adaptor protein alpha-syntrophin is reduced in human non-alcoholic steatohepatitis but is unchanged in hepatocellular carcinoma. Exp Mol Pathol 103:204–209. https://doi.org/10.1016/j.yexmp.2017.09.005
Rein-Fischboeck L, Pohl R, Haberl EM, Zimny S, Neumann M, Eisinger K, Weiss TS, Krautbauer S, Buechler C (2017) Tubulin alpha 8 is expressed in hepatic stellate cells and is induced in transformed hepatocytes. Mol Cell Biochem 428:161–170. https://doi.org/10.1007/s11010-016-2926-4
Rein-Fischboeck L, Haberl EM, Pohl R, Schmid V, Feder S, Krautbauer S, Liebisch G, Buechler C (2018) Alpha-syntrophin null mice are protected from non-alcoholic steatohepatitis in the methionine-choline-deficient diet model but not the atherogenic diet model. Biochim Biophys Acta 1863:526–537. https://doi.org/10.1016/j.bbalip.2018.02.006
Stanchi F, Corso V, Scannapieco P, Ievolella C, Negrisolo E, Tiso N, Lanfranchi G, Valle G (2000) TUBA8: a new tissue-specific isoform of alpha-tubulin that is highly conserved in human and mouse. Biochem Biophys Res Commun 270:1111–1118. https://doi.org/10.1006/bbrc.2000.2571
Vandebrouck A, Sabourin J, Rivet J, Balghi H, Sebille S, Kitzis A, Raymond G, Cognard C, Bourmeyster N, Constantin B (2007) Regulation of capacitative calcium entries by alpha1-syntrophin: association of TRPC1 with dystrophin complex and the PDZ domain of alpha1-syntrophin. FASEB J 21:608–617. https://doi.org/10.1096/fj.06-6683com
Yue F, Li W, Zou J, Jiang X, Xu G, Huang H, Liu L (2017) Spermidine prolongs lifespan and prevents liver fibrosis and hepatocellular carcinoma by activating MAP1S-mediated autophagy. Cancer Res 77:2938–2951. https://doi.org/10.1158/0008-5472.CAN-16-3462
Zhang Y, Yu G, Wang D, Hu Y, Lei W (2011) ERK1/2 activation plays important roles in the opposite effects of Trichostatin A in non-cancer and cancer cells. Toxicon 57:932–937. https://doi.org/10.1016/j.toxicon.2011.03.008
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The study was supported by the German Research Foundation (BU 1141/12-1) to CB.
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Rein-Fischboeck, L., Bajraktari, G., Pohl, R. et al. Alpha-syntrophin dependent expression of tubulin alpha 8 protein in hepatocytes. J Physiol Biochem 74, 511–521 (2018). https://doi.org/10.1007/s13105-018-0645-x
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DOI: https://doi.org/10.1007/s13105-018-0645-x