1. Characterization of two mutations in the SPTLC1 subunit of serine palmitoyltransferase associated with hereditary sensory and autonomic neuropathy type I
- Author
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Kim van Hoof, Michaela Auer-Grumbach, Thorsten Hornemann, Vincent Timmerman, Heinrich Sticht, Anke Penno, Katrien Janssens, Bernd Rautenstrauss, Georg M. Stettner, Bob Asselbergh, Nicholas Levy, Annelies Rotthier, University of Zurich, Timmerman, V, VIB Molecular Genetics, University of Antwerp (UA), Laboratory of Neurogenetics, Clinical Chemistry, University hospital of Zurich [Zurich], Competence Center for Systems Physiology and Metabolic Diseases, Medical Genetics Center, Friedrich-Baur Institute, Ludwig-Maximilians-Universität München (LMU), Department of Internal Medicine, Devision of Endokrinology and Metabolism, Medical University Graz, Department of Pediatrics and Pediatric Neurology, Georg-August-University = Georg-August-Universität Göttingen, Emil-Fischer-Zentrum, Institute of Biochemistry, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Département de génétique médicale [Hôpital de la Timone - APHM], Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)- Hôpital de la Timone [CHU - APHM] (TIMONE)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université de la Méditerranée - Aix-Marseille 2, University Hopital Zurich, Institute of Physiology and Zurich Center for Integrative Human Physiology (ZIHP), Universität Zürich [Zürich] = University of Zurich (UZH), Institute Born-Bunge, University of Antwerp, and Georg-August-University [Göttingen]
- Subjects
2716 Genetics (clinical) ,Protein Conformation ,Protein subunit ,Serine C-Palmitoyltransferase ,Gene Expression ,610 Medicine & health ,Biology ,03 medical and health sciences ,0302 clinical medicine ,1311 Genetics ,Sphingosine ,Hereditary sensory and autonomic neuropathy type I ,540 Chemistry ,Genetics ,medicine ,Humans ,Hereditary Sensory and Autonomic Neuropathies ,SPTLC1 ,Genetics (clinical) ,030304 developmental biology ,10038 Institute of Clinical Chemistry ,0303 health sciences ,Serine C-palmitoyltransferase ,HEK 293 cells ,Life Sciences ,medicine.disease ,Lipids ,Molecular biology ,Sphingolipid ,In vitro ,3. Good health ,HEK293 Cells ,Biochemistry ,Cell culture ,Mutation ,Human medicine ,030217 neurology & neurosurgery - Abstract
International audience; Hereditary sensory and autonomic neuropathy type I (HSAN-I) is an axonal peripheral neuropathy leading to progressive distal sensory loss and severe ulcerations. Mutations in SPTLC1 and SPTLC2, encoding the two subunits of serine palmitoyltransferase (SPT), the enzyme catalyzing the first and rate-limiting step in the de novo synthesis of sphingolipids, have been reported to cause HSAN-I. Here, we demonstrate that the SPTLC1 mutations p.S331F and p.A352V result in a reduction of SPT activity in vitro and are associated with increased levels of the deoxysphingoid bases 1-deoxy-sphinganine and 1-deoxymethyl-sphinganine in patients' plasma samples. Stably expressing p.S331F-SPTLC1 HEK293T cell lines likewise show accumulation of deoxysphingoid bases, but this accumulation is not observed in HEK293T cells overexpressing p.A352V-SPTLC1. These results confirm that the increased formation of deoxysphingoid bases is a key feature for HSAN-I as it is associated with all pathogenic SPTLC1 and SPTLC2 mutations reported so far, but also warrant for caution in the interpretation of in vitro data.
- Published
- 2011
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