Rescue of secretion of rare‐disease‐associated misfolded mutant glycoproteins in UGGT1 knock‐out mammalian cells

Traffic, Journal Year: 2024, Volume and Issue: 25(1)

Published: Jan. 1, 2024

Abstract Endoplasmic reticulum (ER) retention of misfolded glycoproteins is mediated by the ER‐localized eukaryotic glycoprotein secretion checkpoint, UDP‐glucose glucosyl‐transferase (UGGT). The enzyme recognizes a and flags it for ER re‐glucosylating one its N ‐linked glycans. In background congenital mutation in secreted gene, UGGT‐mediated can cause rare disease, even if mutant retains activity (“responsive mutant”). Using confocal laser scanning microscopy, we investigated here subcellular localization human Trop‐2‐Q118E, E227K L186P mutants, which gelatinous drop‐like corneal dystrophy (GDLD). Compared with wild‐type Trop‐2, correctly localized at plasma membrane, these Trop‐2 mutants are retained ER. We studied fluorescent chimeras Q118E, mammalian cells harboring CRISPR/Cas9‐mediated inhibition UGGT1 and/or UGGT2 genes. membrane was successfully rescued −/− cells. also efficiently reglucosylated Trop‐2‐Q118E‐EYFP cellula . study supports hypothesis that modulation would constitute novel therapeutic strategy treatment pathological conditions associated to (whenever impairs but does not abrogate function), encourages testing modulators folding quality control as broad‐spectrum rescue‐of‐secretion drugs diseases caused responsive mutants.

Language: Английский

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Probing biophysical sequence constraints within the transmembrane domains of rhodopsin by deep mutational scanning

Science Advances, Journal Year: 2020, Volume and Issue: 6(10)

Published: March 5, 2020

Membrane proteins must balance the sequence constraints associated with folding and function against hydrophobicity required for solvation within bilayer. We recently found expression maturation of rhodopsin are limited by its seventh transmembrane domain (TM7), which contains polar residues that essential function. On basis these observations, we hypothesized rhodopsin's should be less tolerant mutations in TM7 relative to those hydrophobic TM domains. To test this hypothesis, used deep mutational scanning compare effects 808 missense on plasma membrane HEK293T cells. Our results confirm a higher proportion (37%) decrease (TM2, 25%). These conjunction an evolutionary analysis suggest energetics likely restricts space

Language: Английский

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Computer simulations of protein–membrane systems

Progress in molecular biology and translational science, Journal Year: 2020, Volume and Issue: unknown, P. 273 - 403

Published: Jan. 1, 2020

Language: Английский

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Functional and Biochemical Consequences of Disease Variants in Neurotransmitter Transporters: A Special Emphasis on Folding and Trafficking Deficits

Pharmacology & Therapeutics, Journal Year: 2020, Volume and Issue: 222, P. 107785 - 107785

Published: Dec. 10, 2020

Neurotransmitters, such as γ-aminobutyric acid, glutamate, acetyl choline, glycine and the monoamines, facilitate crosstalk within central nervous system. The designated neurotransmitter transporters (NTTs) both release take up neurotransmitters to from synaptic cleft. NTT dysfunction can lead severe pathophysiological consequences, e.g. epilepsy, intellectual disability, or Parkinson's disease. Genetic point mutations in NTTs have recently been associated with onset of various neurological disorders. Some these trigger folding defects proteins. Correct is a prerequisite for export endoplasmic reticulum (ER) subsequent trafficking their pertinent site action, typically at plasma membrane. Recent studies uncovered some key features molecular machinery responsible transporter protein folding, e.g., role heat shock proteins fine-tuning ER quality control mechanisms cells. therapeutic significance understanding events apparent rising number reports, which directly link different pathological conditions misfolding. For instance, folding-deficient variants human dopamine GABA infantile parkinsonism/dystonia respectively. From view, are amenable functional rescue by small molecules, known chemical pharmacological chaperones.

Language: Английский

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Insights into Membrane Curvature Sensing and Membrane Remodeling by Intrinsically Disordered Proteins and Protein Regions

The Journal of Membrane Biology, Journal Year: 2022, Volume and Issue: 255(2-3), P. 237 - 259

Published: April 22, 2022

Language: Английский

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