Abstract
Hereditary sensory and autonomic neuropathies (HSANs) are a group of clinically and genetically heterogeneous disorders of the peripheral nervous system mainly characterized by impaired nociception and autonomic dysfunction. We previously identified heme metabolism as a novel pathway contributing to sensory neurons maintenance and nociception. Indeed, we reported mutations in the Feline Leukemia Virus subgroup C Receptor 1 (FLVCR1) gene in individuals affected by HSAN. FLVCR1 gene encodes for two heme export proteins, FLVCR1a (plasma membrane) and FLVCR1b (mitochondria), crucially involved in the regulation of cellular heme homeostasis.Here, we report on two additional patients carrying novel biallelic mutations in FLVCR1 translation initiation codon (TIC) (c.2T>C; p. (Met1Thr), c.3G>T; p. (Met1Ile)). We overexpressed the c.2T>C; p. (Met1Thr) mutant in human cell lines and we describe its impact on protein structure and function in comparison with other HSAN related mutations. We found that the mutation interfere with translation in two different ways: by lowering levels of translation of wild-type protein and by inducing translation initiation from a downstream in frame ATG, leading to the production of a N-terminal truncated protein that is retained in the endoplasmic reticulum. The impact of different kinds of mutations on FLVCR1a localization and structure was also described.The identification of novel FLVCR1 mutations in HSAN reinforces the crucial role of heme in sensory neurons maintenance and pain perception. Moreover, our in vitro findings demonstrate that heme export is not completely lost in HSAN patients, thus suggesting the possibility to improve FLVCR1 expression/activity for therapeutic purposes.
| Original language | English |
|---|---|
| Journal | Pain |
| DOIs | |
| Publication status | E-pub ahead of print - Aug 10 2019 |
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Heme and sensory neuropathy : insights from novel mutations in the heme exporter FLVCR1. / Bertino, Francesca; Firestone, Kyra; Bellacchio, Emanuele; Jackson, Kelly E; Asamoah, Alexander; Hersh, Joseph; Fiorito, Veronica; Destefanis, Francesca; Gonser, Rusty; Tucker, Megan E; Altruda, Fiorella; Tolosano, Emanuela; Chiabrando, Deborah.
In: Pain, 10.08.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Heme and sensory neuropathy
T2 - insights from novel mutations in the heme exporter FLVCR1
AU - Bertino, Francesca
AU - Firestone, Kyra
AU - Bellacchio, Emanuele
AU - Jackson, Kelly E
AU - Asamoah, Alexander
AU - Hersh, Joseph
AU - Fiorito, Veronica
AU - Destefanis, Francesca
AU - Gonser, Rusty
AU - Tucker, Megan E
AU - Altruda, Fiorella
AU - Tolosano, Emanuela
AU - Chiabrando, Deborah
PY - 2019/8/10
Y1 - 2019/8/10
N2 - Hereditary sensory and autonomic neuropathies (HSANs) are a group of clinically and genetically heterogeneous disorders of the peripheral nervous system mainly characterized by impaired nociception and autonomic dysfunction. We previously identified heme metabolism as a novel pathway contributing to sensory neurons maintenance and nociception. Indeed, we reported mutations in the Feline Leukemia Virus subgroup C Receptor 1 (FLVCR1) gene in individuals affected by HSAN. FLVCR1 gene encodes for two heme export proteins, FLVCR1a (plasma membrane) and FLVCR1b (mitochondria), crucially involved in the regulation of cellular heme homeostasis.Here, we report on two additional patients carrying novel biallelic mutations in FLVCR1 translation initiation codon (TIC) (c.2T>C; p. (Met1Thr), c.3G>T; p. (Met1Ile)). We overexpressed the c.2T>C; p. (Met1Thr) mutant in human cell lines and we describe its impact on protein structure and function in comparison with other HSAN related mutations. We found that the mutation interfere with translation in two different ways: by lowering levels of translation of wild-type protein and by inducing translation initiation from a downstream in frame ATG, leading to the production of a N-terminal truncated protein that is retained in the endoplasmic reticulum. The impact of different kinds of mutations on FLVCR1a localization and structure was also described.The identification of novel FLVCR1 mutations in HSAN reinforces the crucial role of heme in sensory neurons maintenance and pain perception. Moreover, our in vitro findings demonstrate that heme export is not completely lost in HSAN patients, thus suggesting the possibility to improve FLVCR1 expression/activity for therapeutic purposes.
AB - Hereditary sensory and autonomic neuropathies (HSANs) are a group of clinically and genetically heterogeneous disorders of the peripheral nervous system mainly characterized by impaired nociception and autonomic dysfunction. We previously identified heme metabolism as a novel pathway contributing to sensory neurons maintenance and nociception. Indeed, we reported mutations in the Feline Leukemia Virus subgroup C Receptor 1 (FLVCR1) gene in individuals affected by HSAN. FLVCR1 gene encodes for two heme export proteins, FLVCR1a (plasma membrane) and FLVCR1b (mitochondria), crucially involved in the regulation of cellular heme homeostasis.Here, we report on two additional patients carrying novel biallelic mutations in FLVCR1 translation initiation codon (TIC) (c.2T>C; p. (Met1Thr), c.3G>T; p. (Met1Ile)). We overexpressed the c.2T>C; p. (Met1Thr) mutant in human cell lines and we describe its impact on protein structure and function in comparison with other HSAN related mutations. We found that the mutation interfere with translation in two different ways: by lowering levels of translation of wild-type protein and by inducing translation initiation from a downstream in frame ATG, leading to the production of a N-terminal truncated protein that is retained in the endoplasmic reticulum. The impact of different kinds of mutations on FLVCR1a localization and structure was also described.The identification of novel FLVCR1 mutations in HSAN reinforces the crucial role of heme in sensory neurons maintenance and pain perception. Moreover, our in vitro findings demonstrate that heme export is not completely lost in HSAN patients, thus suggesting the possibility to improve FLVCR1 expression/activity for therapeutic purposes.
U2 - 10.1097/j.pain.0000000000001675
DO - 10.1097/j.pain.0000000000001675
M3 - Article
JO - Pain
JF - Pain
SN - 0304-3959
ER -