Disrupting dimerization translocates soluble epoxide hydrolase to peroxisomes

Jonathan W. Nelson, Anjali J. Das, Anthony Barnes, Nabil Alkayed

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The epoxyeicosatrienoic acid (EET) neutralizing enzyme soluble epoxide hydrolase (sEH) is a neuronal enzyme, which has been localized in both the cytosol and peroxisomes. The molecular basis for its dual localization remains unclear as sEH contains a functional peroxisomal targeting sequence (PTS). Recently, a missense polymorphism was identified in human sEH (R287Q) that enhances its peroxisomal localization. This same polymorphism has also been shown to generate weaker sEH homo-dimers. Taken together, these observations suggest that dimerization may mask the sEH PTS and prevent peroxisome translocation. In the current study, we test the hypothesis that dimerization is a key regulator of sEH subcellular localization. Specifically, we altered the dimerization state of sEH by introducing substitutions in amino acids responsible for the dimer-stabilizing salt-bridge. Green Fluorescent Protein (GFP) fusions of each of mutants were co-transfected into mouse primary cultured cortical neurons together with a PTS-linked red fluorescent protein to constitutively label peroxisomes. Labeled neurons were analyzed using confocal microscopy and co-localization of sEH with peroxisomes was quantified using Pearson's correlation coefficient. We find that dimer-competent sEH constructs preferentially localize to the cytosol, whereas constructs with weakened or disrupted dimerization were preferentially targeted to peroxisomes. We conclude that the sEH dimerization status is a key regulator of its peroxisomal localization.

Original languageEnglish (US)
Article numbere0152742
JournalPLoS One
Volume11
Issue number5
DOIs
StatePublished - May 1 2016

Fingerprint

epoxide hydrolase
Epoxide Hydrolases
Peroxisomes
dimerization
Dimerization
peroxisomes
Dimers
Polymorphism
cytosol
Cytosol
Neurons
neurons
genetic polymorphism
Confocal microscopy
Homo
amino acid substitution
Enzymes
Amino Acid Substitution
Masks
enzymes

ASJC Scopus subject areas

  • Medicine(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Cite this

Disrupting dimerization translocates soluble epoxide hydrolase to peroxisomes. / Nelson, Jonathan W.; Das, Anjali J.; Barnes, Anthony; Alkayed, Nabil.

In: PLoS One, Vol. 11, No. 5, e0152742, 01.05.2016.

Research output: Contribution to journalArticle

@article{d936e69041c14393b4eb0bf0fbbe22a9,
title = "Disrupting dimerization translocates soluble epoxide hydrolase to peroxisomes",
abstract = "The epoxyeicosatrienoic acid (EET) neutralizing enzyme soluble epoxide hydrolase (sEH) is a neuronal enzyme, which has been localized in both the cytosol and peroxisomes. The molecular basis for its dual localization remains unclear as sEH contains a functional peroxisomal targeting sequence (PTS). Recently, a missense polymorphism was identified in human sEH (R287Q) that enhances its peroxisomal localization. This same polymorphism has also been shown to generate weaker sEH homo-dimers. Taken together, these observations suggest that dimerization may mask the sEH PTS and prevent peroxisome translocation. In the current study, we test the hypothesis that dimerization is a key regulator of sEH subcellular localization. Specifically, we altered the dimerization state of sEH by introducing substitutions in amino acids responsible for the dimer-stabilizing salt-bridge. Green Fluorescent Protein (GFP) fusions of each of mutants were co-transfected into mouse primary cultured cortical neurons together with a PTS-linked red fluorescent protein to constitutively label peroxisomes. Labeled neurons were analyzed using confocal microscopy and co-localization of sEH with peroxisomes was quantified using Pearson's correlation coefficient. We find that dimer-competent sEH constructs preferentially localize to the cytosol, whereas constructs with weakened or disrupted dimerization were preferentially targeted to peroxisomes. We conclude that the sEH dimerization status is a key regulator of its peroxisomal localization.",
author = "Nelson, {Jonathan W.} and Das, {Anjali J.} and Anthony Barnes and Nabil Alkayed",
year = "2016",
month = "5",
day = "1",
doi = "10.1371/journal.pone.0152742",
language = "English (US)",
volume = "11",
journal = "PLoS One",
issn = "1932-6203",
publisher = "Public Library of Science",
number = "5",

}

TY - JOUR

T1 - Disrupting dimerization translocates soluble epoxide hydrolase to peroxisomes

AU - Nelson, Jonathan W.

AU - Das, Anjali J.

AU - Barnes, Anthony

AU - Alkayed, Nabil

PY - 2016/5/1

Y1 - 2016/5/1

N2 - The epoxyeicosatrienoic acid (EET) neutralizing enzyme soluble epoxide hydrolase (sEH) is a neuronal enzyme, which has been localized in both the cytosol and peroxisomes. The molecular basis for its dual localization remains unclear as sEH contains a functional peroxisomal targeting sequence (PTS). Recently, a missense polymorphism was identified in human sEH (R287Q) that enhances its peroxisomal localization. This same polymorphism has also been shown to generate weaker sEH homo-dimers. Taken together, these observations suggest that dimerization may mask the sEH PTS and prevent peroxisome translocation. In the current study, we test the hypothesis that dimerization is a key regulator of sEH subcellular localization. Specifically, we altered the dimerization state of sEH by introducing substitutions in amino acids responsible for the dimer-stabilizing salt-bridge. Green Fluorescent Protein (GFP) fusions of each of mutants were co-transfected into mouse primary cultured cortical neurons together with a PTS-linked red fluorescent protein to constitutively label peroxisomes. Labeled neurons were analyzed using confocal microscopy and co-localization of sEH with peroxisomes was quantified using Pearson's correlation coefficient. We find that dimer-competent sEH constructs preferentially localize to the cytosol, whereas constructs with weakened or disrupted dimerization were preferentially targeted to peroxisomes. We conclude that the sEH dimerization status is a key regulator of its peroxisomal localization.

AB - The epoxyeicosatrienoic acid (EET) neutralizing enzyme soluble epoxide hydrolase (sEH) is a neuronal enzyme, which has been localized in both the cytosol and peroxisomes. The molecular basis for its dual localization remains unclear as sEH contains a functional peroxisomal targeting sequence (PTS). Recently, a missense polymorphism was identified in human sEH (R287Q) that enhances its peroxisomal localization. This same polymorphism has also been shown to generate weaker sEH homo-dimers. Taken together, these observations suggest that dimerization may mask the sEH PTS and prevent peroxisome translocation. In the current study, we test the hypothesis that dimerization is a key regulator of sEH subcellular localization. Specifically, we altered the dimerization state of sEH by introducing substitutions in amino acids responsible for the dimer-stabilizing salt-bridge. Green Fluorescent Protein (GFP) fusions of each of mutants were co-transfected into mouse primary cultured cortical neurons together with a PTS-linked red fluorescent protein to constitutively label peroxisomes. Labeled neurons were analyzed using confocal microscopy and co-localization of sEH with peroxisomes was quantified using Pearson's correlation coefficient. We find that dimer-competent sEH constructs preferentially localize to the cytosol, whereas constructs with weakened or disrupted dimerization were preferentially targeted to peroxisomes. We conclude that the sEH dimerization status is a key regulator of its peroxisomal localization.

UR - http://www.scopus.com/inward/record.url?scp=84991519027&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84991519027&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0152742

DO - 10.1371/journal.pone.0152742

M3 - Article

C2 - 27203283

AN - SCOPUS:84991519027

VL - 11

JO - PLoS One

JF - PLoS One

SN - 1932-6203

IS - 5

M1 - e0152742

ER -