title: NTE/PNPLA6 is expressed in mature Schwann cells and is required for glial ensheathment of Remak fibers.
abstract: Neuropathy target esterase (NTE) or patatin-like phospholipase domain containing 6 (PNPLA6) was first linked with a neuropathy occurring after organophosphate poisoning and was later also found to cause complex syndromes when mutated, which can include mental retardation, spastic paraplegia, ataxia, and blindness. NTE/PNPLA6 is widely expressed in neurons but experiments with its Drosophila orthologue Swiss-cheese (SWS) suggested that it may also have glial functions. Investigating whether NTE/PNPLA6 is expressed in glia, we found that NTE/PNPLA6 is expressed by Schwann cells in the sciatic nerve of adult mice with the most prominent expression in nonmyelinating Schwann cells. Within Schwann cells, NTE/PNPLA6 is enriched at the Schmidt-Lanterman incisures and around the nucleus. When analyzing postnatal expression patterns, we did not detect NTE/PNPLA6 in promyelinating Schwann cells, while weak expression was detectable at postnatal day 5 in Schwann cells and increased with their maturation. Interestingly, NTE/PNPLA6 levels were upregulated after nerve crush and localized to ovoids forming along the nerve fibers. Using a GFAP-based knock-out of NTE/PNPLA6, we detected an incomplete ensheathment of Remak fibers whereas myelination did not appear to be affected. These results suggest that NTE/PNPLA6 is involved in the maturation of nonmyelinating Schwann cells during development and de-/remyelination after neuronal injury. Since Schwann cells play an important role in maintaining axonal viability and function, it is therefore likely that changes in Schwann cells contribute to the locomotory deficits and neuropathy observed in patients carrying mutations in NTE.
authors.affiliation: Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.
authors.forename: Janis
authors.initials: J
authors.lastname: McFerrin
authors.affiliation: Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Patton
authors.affiliation: Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.|Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Sunderhaus
authors.affiliation: Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.|Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.
authors.forename: Doris
authors.identifier: 0000-0002-0519-2377
authors.initials: D
authors.lastname: Kretzschmar
mesh_terms: D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism*; D008810:Mice, Inbred C57BL; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D055495:Neurogenesis / Q000235:genetics; D009457:Neuroglia / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D010740:Phospholipases / Q000378:metabolism*; D012583:Schwann Cells / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D009419:Nerve Tissue Proteins; D010740:Phospholipases; D002265:Carboxylic Ester Hydrolases; C021859:neurotoxic esterase
keywords: Drosophila SWS; nerve injury; neuropathy; nonmyelinating Schwann cells; spastic paraplegia