The Glu102 mutation disrupts higher-order oligomerization of the sigma 1 receptor

Abramyan, Ara M.; Yano, Hideaki; Xu, Min; Liu, Leanne; Naing, Sett; Fant, Andrew D.; Shi, Lei

doi:10.1016/j.csbj.2019.12.012

Cited by 16 publications

(18 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They found that most of the agonists decrease multimer formation with a molecular weight of over 130 kDa, whereas antagonists increase such formations. Their results also showed that σ1R E102Q reduces multimer or high-order oligomers over dimers (49,50). In our study, σ1R-mCh formed exclusively monomers and dimers, while σ1R E102Q -mCh was also observed in trimers and tetramers ( Fig.…”

Section: Discussionsupporting

confidence: 80%

“…SA4503 treatment decreased the formation of these four oligomeric states in the insoluble fraction, but increased the accumulation of monomers in the soluble fraction. The effects of agonists and antagonists on the oligomeric state of σ1R were recently investigated by another group (47)(48)(49)(50), who transfected HEK293 cells with non-tagged or tagged forms of σ1R and performed normal SDS-PAGE or PAGE with mild detergents (perfluorooctanoic acid or sodium lauroyl sarcosinate). They found that most of the agonists decrease multimer formation with a molecular weight of over 130 kDa, whereas antagonists increase such formations.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Wildtype σ1 receptor and the receptor agonist improve ALS-associated mutation-induced insolubility and toxicity

Shinoda

Haga

Akagawa

et al. 2020

Journal of Biological Chemistry

View full text Add to dashboard Cite

Genetic mutations related to amyotrophic lateral sclerosis (ALS), a progressive neurological disease, have been discovered in the gene encoding sigma-1 receptor (σ1R). We previously reported that σ1RE102Q elicits toxicity in cells. The σ1R forms oligomeric states that are regulated by ligands. Nevertheless, little is known about the effect of ALS-related mutations on oligomer formation. Here, we transfected NSC-34 cells, a motor neuronal cell line, and HEK293T cells with σ1R-mCherry (mCh), σ1RE102Q-mCh or non-tagged forms to investigate detergent solubility and subcellular distribution using immunocytochemistry and fluorescence recovery after photobleaching (FRAP). The oligomeric state was determined using crosslinking procedure. σ1Rs were solubleto detergents, whereas the mutants accumulated in the insoluble fraction. Within the soluble fraction, peak distribution of mutants appeared in higher sucrose density fractions. Mutants formed intracellular aggregates that were costained with p62, ubiquitin, and phosphorylated pancreatic eukaryotic translation initiation factor-2-alpha kinase in NSC-34 cells but not in HEK293T cells. The aggregates had significantly lower recovery in FRAP. Acute treatment with σ1R agonist SA4503 failed to improve recovery, while prolonged treatment for 48 h significantly decreased σ1RE102Q-mCh insolubility and inhibited apoptosis. While σ1R-mCh formed monomers and dimers, σ1RE102Q-mCh also formed trimers and tetramers. SA4503 reduced accumulation of the four types in the insoluble fraction and increased monomers in the soluble fraction. The σ1RE102Q insolubility was diminished by σ1R-mCh co-expression. These results suggest the agonist and wildtype σ1R modify the detergent insolubility, toxicity, and oligomeric state of σ1RE102Q which may lead to promising new treatments for σ1R-related ALS.

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Discussionmentioning

confidence: 99%

Wildtype σ1 receptor and the receptor agonist improve ALS-associated mutation-induced insolubility and toxicity

Shinoda

Haga

Akagawa

et al. 2020

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…Therefore, the reduced σ1R-σ1R interaction may arise from the membrane environment in which σ1R is localized such that the σ1R density may be too low to find an interacting partner. Further, while the exterior of the barrel motif of the C-terminal domain has been revealed by the crystal structures to be the interface for trimer, it is likely other part of the of the protein involves in forming other oligomer states, such as the N-terminus and N-terminal transmembrane helix [21]. The Nterminal tagging may potentially bias the protein towards dimer formation by facilitating the interactions between two monomers at their N-terminal region.…”

mentioning

confidence: 99%

The effects of terminal tagging on homomeric interactions of the sigma 1 receptor

Yano

Liu

Naing

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

The sigma 1 receptor (σ1R) has been implicated in cancers, neurological disorders, and substance use disorders. Yet, its molecular and cellular functions have not been well-understood.Recent crystal structures of σ1R reveal a single N-terminal transmembrane segment and Cterminal ligand-binding domain, and a trimeric organization. Nevertheless, outstanding issues surrounding the functional or pharmacological relevance of σ1R oligomerization remain, such as the minimal protomeric unit and the differentially altered oligomerization states by different classes of ligands. Western blot (WB) assays have been widely used to investigate protein oligomerizations. However, the unique topology of σ1R renders several intertwined challenges in WB. Here we describe a WB protocol without temperature denaturization to study the ligand binding effects on the oligomerization state of σ1R. Using this approach, we observed unexpected ladder-like incremental migration pattern of σ1R, demonstrating preserved homomeric interactions in the detergent environment. We compared the migration patterns of intact σ1Rconstruct and the C-terminally tagged σ1R constructs, and found similar trends in response to drug treatments. In contrast, N-terminally tagged σ1R constructs show opposite trends to that of the intact construct, suggesting distorted elicitation of the ligand binding effects on oligomerization.Together, our findings indicate that the N-terminus plays an important role in eliciting the impacts of bound ligands, whereas the C-terminus is amenable for modifications for biochemical studies.

show abstract

“…E102 forms a hydrogen bond with Y173 in β10 [ 52 ] and a pair of hydrogen bonds with the backbone amide nitrogen atoms of V36 and F37, which are part of a structured tether between the transmembrane domain and cytosolic domain. The E102Q mutation abolishes the negatively charged cluster located in the linker region between β2 and β3 (residues 98–106, ASLSEYVLL) and alters hydrogen-bonding properties at the junction between the N-terminal helix and the C-terminal domain adjacent to the ligand-binding pocket of σ1R [ 29 ].…”

Section: Discussionmentioning

confidence: 99%

“…The E102Q mutation abolishes the negatively charged cluster located in the linker region between β2 and β3 (residues 98–106, ASLSEYVLL) and alters hydrogen-bonding properties at the junction between the N-terminal helix and the C-terminal domain adjacent to the ligand-binding pocket of σ1R [ 29 ]. This mutation does not impede the binding of ligands to σ1R, as observed in ligand binding assays [ 52 ], but modifies the affinity of σ1R for target proteins and its response to cytosolic calcium levels. It also abolishes the effects of ligand binding on the formation of complexes between σ1R and regulated signaling proteins.…”

Section: Discussionmentioning

confidence: 99%

The ALS-Related σ1R E102Q Mutant Eludes Ligand Control and Exhibits Anomalous Response to Calcium

Rodríguez-Muñoz

Cortés-Montero

Garzón

et al. 2020

IJMS

View full text Add to dashboard Cite

Sigma receptor type 1 (σ1R) is a transmembrane protein expressed throughout the central nervous system and in certain peripheral tissues. The human σ1R E102Q mutation causes juvenile amyotrophic lateral sclerosis (ALS), likely by inducing a series of alterations in calcium efflux from the endoplasmic reticulum (ER) to mitochondria that affects calcium homeostasis and cellular survival. Here, we report the influence of calcium on σ1R E102Q associations with glutamate N-methyl-D-aspartate receptors (NMDARs), binding immunoglobulin protein (BiP), and transient receptor potential calcium channels A1, V1, and M8. The mutant protein inhibited the binding of calmodulin to these calcium channels and interacted less with BiP than wild-type σ1R, thereby contributing to calcium homeostasis dysfunction. Mutant σ1R, but not wild-type σ1R, strongly bound to histidine triad nucleotide binding protein 1, which regulates neuromuscular synaptic organization and target selection through teneurin 1. While ligands regulated the association of σ1R wild-type with NMDARs and BiP, they failed to modulate the interaction between these proteins and the σ1R E102Q mutant. Thus, the σ1R E102Q mutant exhibited an anomalous response to cytosolic calcium levels, altered affinity for target proteins, and a loss of response to regulatory ligands. We believe that these modifications may contribute to the onset of juvenile ALS.

show abstract

The Glu102 mutation disrupts higher-order oligomerization of the sigma 1 receptor

Cited by 16 publications

References 31 publications

Wildtype σ1 receptor and the receptor agonist improve ALS-associated mutation-induced insolubility and toxicity

Wildtype σ1 receptor and the receptor agonist improve ALS-associated mutation-induced insolubility and toxicity

The effects of terminal tagging on homomeric interactions of the sigma 1 receptor

The ALS-Related σ1R E102Q Mutant Eludes Ligand Control and Exhibits Anomalous Response to Calcium

Contact Info

Product

Resources

About