Skip to main content
SpringerLink
Log in

Abnormal Expression of FBXL20 in Refractory Epilepsy Patients and a Pilocarpine-Induced Rat Model

  • Original Paper
  • Published:
Neurochemical Research Aims and scope Submit manuscript

Abstract

E3 ubiquitin ligases are important protein-modifying enzymes involved in the pathogenesis of a variety of neurodegenerative diseases. F-box and leucine-rich repeat protein 20 (FBXL20), an E3 ubiquitin ligase widely expressed in the central nervous system, plays an important role in the ubiquitin-dependent degradation of regulating synaptic membrane exocytosis 1 (RIM1), which is an important factor in the release of synaptic vesicles. FBXL20 has been associated with a variety of neurodegenerative diseases; thus, we hypothesized that FBXL20 is involved in the development of epilepsy. Herein, we used immunofluorescence staining, immunohistochemistry and western blotting to determine the expression pattern of FBXL20 in temporal lobe epilepsy patients and pilocarpine-induced epilepsy animal models. We also injected SD rats with lentivirus-vector mediated overexpression of FBXL20. The results showed that FBXL20 is expressed in the membrane and the cytoplasm of cortical neurons, and overexpression of FBXL20 decreased the onset level of spontaneous seizure, the frequency and duration of seizures. Additionally, FBXL20 protein level was decreased but RIM1 protein level was increased in the epileptic group compared with the LV-FBXL20 and LV-GFP group. These findings in humans were consistent with the results from a pilocarpine-induced animal model of chronic epilepsy. Thus, abnormal expression of FBXL20 might play an important role in the development of epilepsy.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

Abbreviations

FBXL20:

F-box and leucine-rich repeat protein 20

Rim1:

Regulating synaptic membrane exocytosis 1

TLE:

Temporal lobe epilepsy

CNS:

Central nervous system

UPS:

Ubiquitin-proteasome system

AEDs:

Anti-epileptic drugs

EEG:

Electroencephalography

F:

Female

M:

Male

VPA:

Valproate

PB:

Phenobarbital

CBZ:

Carbamazepine

TPM:

Topiramate

PHT:

Phenytoin

LTG:

Lamotrigine

OXC:

Oxcarbazepine

LEV:

Levetiracetam

TN:

Temporal neocortex

l:

Left

r:

Right

NL:

Neuronal necrosis

G:

Gliosis

SD rats:

Sprague-Dawley rats

IHC:

Immunohistochemical

IF:

Immunofluorescence

MRI:

Magnetic resonance imaging

SE:

Status epilepticus

RT-PCR:

Real-time PCR

References

  1. Leach JP, Abassi H (2013) Modern management of epilepsy. Clin Med 13(1):84–86

    Article  CAS  Google Scholar 

  2. Bae YS, Chung W, Han K et al (2013) Down-regulation of RalBP1 expression reduces seizure threshold and synaptic inhibition in mice. Biochem Biophys Res Commun 433(2):175–180

    Article  CAS  PubMed  Google Scholar 

  3. Dulac O, Milh M, Holmes GL (2012) Brain maturation and epilepsy. Handbook Clin Neurol 111:441–446

    Article  Google Scholar 

  4. Yang X, Xu X, Zhang Y et al (2015) Altered expression of intersectin1-L in patients with refractory epilepsy and in experimental epileptic rats. Cell Mol Neurobiol 35(6):871–880

    Article  CAS  PubMed  Google Scholar 

  5. Cousin MA, Robinson PJ (1999) Mechanisms of synaptic vesicle recycling illuminated by fluorescent dyes. J Neurochem 3(6):2227–2239

    Google Scholar 

  6. Yao I, Takagi H, Ageta H et al (2007) SCRAPPER-dependent ubiquitination of active zone protein RIM1 regulates synaptic vesicle release. Cell 130(5):943–957

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. ] Pitsch J, Opitz T, Borm V et al (2012) The presynaptic active zone protein RIM1α controls epileptogenesis following status epilepticus. J Neurosci 32(36):12384–12395

    Article  CAS  PubMed  Google Scholar 

  8. Martin BS, Huntsman MM (2012) Pathological plasticity in fragile X syndrome. Neural Plast. doi:10.1155/2012/275630

    PubMed  PubMed Central  Google Scholar 

  9. Holderith N, Lorincz A, Katona G et al (2012) Release probability of hippocampal glutamatergic terminals scales with the size of the active zone. Nat Neurosci 15(7):988–997

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Upreti C, Otero R, Partida C et al (2012) Altered neurotransmitter release, vesicle recycling and presynaptic structure in the pilocarpine model of temporal lobe epilepsy. Brain 135(3):869–885

    Article  PubMed  PubMed Central  Google Scholar 

  11. Crabtree GW, Gogos JA (2014) Synaptic plasticity, neural circuits, and the emerging role of altered short-term information processing in schizophrenia. Front Synaptic Neurosci 6:28

    Article  PubMed  PubMed Central  Google Scholar 

  12. Minassian BA, Lee JR, Herbrick JA et al (1998) Mutations in a gene encoding a novel protein tyrosine phosphatase cause progressive myoclonus epilepsy. Nat Genet 20(2):171–174

    Article  CAS  PubMed  Google Scholar 

  13. Minassian BA (2002) Progressive myoclonus epilepsy with polyglucosan bodies: lafora disease. Advan Neurol 89:199

    PubMed  Google Scholar 

  14. Chan EM, Young EJ, Ianzano L et al (2003) Mutations in NHLRC1 cause progressive myoclonus epilepsy. Nat Genet 35(2):125–127

    Article  CAS  PubMed  Google Scholar 

  15. Girach F, Craig TJ, Rocca DL et al (2013) RIM1α SUMOylation is required for fast synaptic vesicle exocytosis. Cell Reports 5(5):1294–1301

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Wu L, Peng J, Kong H et al (2015) The role of ubiquitin/Nedd4-2 in the pathogenesis of mesial temporal lobe epilepsy. Physiol Behav 143:104–112

    Article  CAS  PubMed  Google Scholar 

  17. Liu J, Ye J, Zou X et al (2014) CRL4ACRBN E3 ubiquitin ligase restricts BK channel activity and prevents epileptogenesis. Nat Commun 5:3924

    CAS  PubMed  Google Scholar 

  18. Yao I, Takao K, Miyakawa T et al (2011) Synaptic E3 ligase SCRAPPER in contextual fear conditioning: extensive behavioral phenotyping of Scrapper heterozygote and overexpressing mutant mice. PLoS One 6(2):e17317

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Jin J, Cardozo T, Lovering RC et al (2004) Systematic analysis and nomenclature of mammalian F-box proteins. Genes Dev 18(21):2573–2580

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Kintscher M, Wozny C, Johenning FW et al (2013) Role of RIM1α in short- and long-term synaptic plasticity at cerebellar parallel fibres. Nat Commun 4:2392

    Article  PubMed  Google Scholar 

  21. Kiyonaka S, Wakamori M, Miki T et al (2007) RIM1 confers sustained activity and neurotransmitter vesicle anchoring to presynaptic Ca2+ channels. Nat Neurosci 10(6):691–701

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Schoch S, Castillo PE, Jo T et al (2002) RIM1α forms a protein scaffold for regulating neurotransmitter release at the active zone. Nature 415(6869):321–326

    Article  CAS  PubMed  Google Scholar 

  23. Han Y, Kaeser PS, Südhof TC et al (2011) RIM determines Ca2+ channel density and vesicle docking at the presynaptic active zone. Neuron 69(2):304–316

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Weiss N, Sandoval A, Kyonaka S et al (2011) Rim1 modulates direct G-protein regulation of CaV2.2 channels, Pflügers Arch 461(4):447–459

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgments

This work was supported by the Foundation of Chongqing Health Bureau (2013-1-005), and supported by the National key clinical specialty construction projects [2011-170]. We sincerely thank the support of Xuanwu Hospital and Tiantan Hospital of Capital Medical University, Xinqiao Hospital of the Third Military Medical University, and the First Affiliated Hospital of Chongqing Medical University, which provided the brain tissue samples. We also feel grateful for the patients and their families who participated in this study.

Author information

Authors and Affiliations

  1. Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China

    Pengfei Fu, YueTao Wen, Yanfeng Xie & Quanhong Shi

  2. Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China

    Yan Xiong & Yanke Zhang

  3. Department of Pediatric Intensive Care Unit, West China Second University Hospital, Sichuan University, Chengdu, 610000, China

    Haiyang Zhang

Authors
  1. Pengfei Fu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. YueTao Wen
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yan Xiong
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yanke Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Haiyang Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Yanfeng Xie
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Quanhong Shi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Quanhong Shi.

Ethics declarations

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approval

All procedures performed in the study involving human participants were in accordance with the ethical standards of the Chongqing Medical University and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fu, P., Wen, Y., Xiong, Y. et al. Abnormal Expression of FBXL20 in Refractory Epilepsy Patients and a Pilocarpine-Induced Rat Model. Neurochem Res 41, 3020–3031 (2016). https://doi.org/10.1007/s11064-016-2021-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11064-016-2021-y

Keywords

Search

Navigation