Missense mutations in transmembrane domains of proteins: Phenotypic propensity of polar residues for human disease

The heterodimeric ATP-binding cassette (ABC) sterol transporter, ABCG5/G8, is responsible for the biliary and transintestinal secretion of cholesterol and dietary plant sterols. Missense mutations of ABCG5/G8 can cause sitosterolemia, a loss-of-function disorder characterized by plant sterol accumulation and premature atherosclerosis. A new molecular framework was recently established by a crystal structure of human ABCG5/G8 and reveals a network of polar and charged amino acids in the core of the transmembrane domains, namely, a polar relay. In this study, we utilize genetic variants to dissect the mechanistic role of this transmembrane polar relay in controlling ABCG5/G8 function. We demonstrated a sterol-coupled ATPase activity of ABCG5/G8 by cholesteryl hemisuccinate (CHS), a relatively water-soluble cholesterol memetic, and characterized CHS-coupled ATPase activity of three loss-of-function missense variants, R543S, E146Q, and A540F, which are respectively within, in contact with, and distant from the polar relay. The results established an in vitro phenotype of the loss-of-function and missense mutations of ABCG5/G8, showing significantly impaired ATPase activity and loss of energy sufficient to weaken the signal transmission from the transmembrane domains. Our data provide a biochemical evidence underlying the importance of the polar relay and its network in regulating the catalytic activity of ABCG5/G8 sterol transporter.

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Human disease-causing NOG missense mutations: Effects on noggin secretion, dimer formation, and bone morphogenetic protein binding

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.201367598 ◽

2001 ◽

Vol 98 (20) ◽

pp. 11353-11358 ◽

Cited By ~ 64

Author(s):

J. Marcelino ◽

C. M. Sciortino ◽

M. F. Romero ◽

L. M. Ulatowski ◽

R. T. Ballock ◽

...

Keyword(s):

Protein Binding ◽

Bone Morphogenetic Protein ◽

Human Disease ◽

Missense Mutations ◽

Dimer Formation ◽

Morphogenetic Protein

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The Cytoplasmic End of Transmembrane Domain 3 Regulates the Activity of the Saccharomyces cerevisiae G-Protein-Coupled α-Factor Receptor

Genetics ◽

10.1093/genetics/160.2.429 ◽

2002 ◽

Vol 160 (2) ◽

pp. 429-443

Author(s):

William Parrish ◽

Markus Eilers ◽

Weiwen Ying ◽

James B Konopka

Keyword(s):

G Protein ◽

Transmembrane Domain ◽

Transmembrane Helix ◽

G Protein Coupled Receptors ◽

Transmembrane Domains ◽

Targeted Mutagenesis ◽

Activating Mutations ◽

Polar Residues ◽

Domain 3 ◽

G Protein Coupled

Abstract The binding of α-factor to its receptor (Ste2p) activates a G-protein-signaling pathway leading to conjugation of MATa cells of the budding yeast S. cerevisiae. We conducted a genetic screen to identify constitutively activating mutations in the N-terminal region of the α-factor receptor that includes transmembrane domains 1–5. This approach identified 12 unique constitutively activating mutations, the strongest of which affected polar residues at the cytoplasmic ends of transmembrane domains 2 and 3 (Asn84 and Gln149, respectively) that are conserved in the α-factor receptors of divergent yeast species. Targeted mutagenesis, in combination with molecular modeling studies, suggested that Gln149 is oriented toward the core of the transmembrane helix bundle where it may be involved in mediating an interaction with Asn84. These residues appear to play specific roles in maintaining the inactive conformation of the protein since a variety of mutations at either position cause constitutive receptor signaling. Interestingly, the activity of many mammalian G-protein-coupled receptors is also regulated by conserved polar residues (the E/DRY motif) at the cytoplasmic end of transmembrane domain 3. Altogether, the results of this study suggest a conserved role for the cytoplasmic end of transmembrane domain 3 in regulating the activity of divergent G-protein-coupled receptors.

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Polar Residues in the Transmembrane Domains of the Type 1 Angiotensin II Receptor Are Required for Binding and Coupling

Journal of Biological Chemistry ◽

10.1074/jbc.271.3.1507 ◽

1996 ◽

Vol 271 (3) ◽

pp. 1507-1513 ◽

Cited By ~ 150

Author(s):

Catherine Monnot ◽

Claire Bihoreau ◽

Sophie Conchon ◽

Kathleen M. Curnow ◽

Pierre Corvol ◽

...

Keyword(s):

Angiotensin Ii ◽

Transmembrane Domains ◽

Angiotensin Ii Receptor ◽

Polar Residues

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The Contribution of Missense Mutations in Core and Rim Residues of Protein–Protein Interfaces to Human Disease

Journal of Molecular Biology ◽

10.1016/j.jmb.2015.07.004 ◽

2015 ◽

Vol 427 (17) ◽

pp. 2886-2898 ◽

Cited By ~ 57

Author(s):

Alessia David ◽

Michael J.E. Sternberg

Keyword(s):

Human Disease ◽

Missense Mutations ◽

Protein Interfaces

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Biases in arginine codon usage correlate with genetic disease risk

10.1101/825703 ◽

2019 ◽

Author(s):

Katharina V. Schulze ◽

Neil A. Hanchard ◽

Michael F. Wangler

Keyword(s):

Codon Usage ◽

Genetic Disease ◽

Human Disease ◽

Disease Risk ◽

Single Gene ◽

Autism Spectrum ◽

Disease Genes ◽

Missense Mutations ◽

Loss Of Function ◽

Human Genetic Disease

ABSTRACTPurposeThe persistence of hypermutable ‘CGN’ (CGG, CGA, CGC, CGU) arginine codons at high frequency suggests the possibility of negative selective pressure at these sites and that arginine codon usage could be a predictive indicator of human disease genes.MethodsWe analyzed arginine codons (CGN, AGG, AGA) from all ‘canonical’ Ensembl protein coding gene transcripts before comparing the frequency of CGN codons between genes with and without human disease associations and with gnomAD constraint metrics.ResultsThe frequency of CGN codons among a gene’s total arginine codon count was higher in genes linked to syndromic autism spectrum disorder (ASD) compared to genes not associated with ASD. A comparison of genes annotated as dominant or recessive with control genes not matching either classification revealed a progressive increase in CGN codon frequency. Moreover, CGN frequency was positively correlated with a gene’s probability of loss-of-function intolerance (pLI) score and negatively correlated with ‘observed-over-expected’ ratios for both loss of function and missense mutations.ConclusionOur findings indicate that genes utilizing CGN arginine codons rather than AGG or AGA are more likely to underlie single gene disorders, particularly for dominant phenotypes, and thus constitute candidate genes for the study of human genetic disease.

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Transmembrane polar relay drives the allosteric regulation for ABCG5/G8 sterol transporter

10.1101/2020.10.06.327825 ◽

2020 ◽

Author(s):

Bala M. Xavier ◽

Aiman A. Zein ◽

Angelica Venes ◽

Junmei Wang ◽

Jyh-Yeuan Lee

Keyword(s):

Atpase Activity ◽

Signal Transmission ◽

Transmembrane Domains ◽

Water Soluble ◽

Missense Mutations ◽

Loss Of Function ◽

Charged Amino Acids ◽

Cholesteryl Hemisuccinate

AbstractThe heterodimeric ATP-binding cassette (ABC) sterol transporter, ABCG5/G8, is responsible for the biliary and transintestinal secretion of cholesterol and dietary plant sterols. Missense mutations of ABCG5/G8 can cause sitosterolemia, a loss-of-function disorder characterized by plant sterol accumulation and premature atherosclerosis. A new molecular framework was recently established by a crystal structure of human ABCG5/G8 and reveals a network of polar and charged amino acids in the core of the transmembrane domains, namely polar relay. In this study, we utilize genetic variants to dissect the mechanistic role of this transmembrane polar relay in controlling ABCG5/G8 function. We demonstrated a sterol-coupled ATPase activity of ABCG5/G8 by cholesteryl hemisuccinate (CHS), a relatively water-soluble cholesterol memetic, and characterized CHS-coupled ATPase activity of three loss-of-function missense variants, R543S, E146Q, and A540F, which are respectively within, in contact with, and distant from the polar relay. The results established an in vitro phenotype of the loss-of-function and missense mutations of ABCG5/G8, showing significantly impaired ATPase activity and loss of energy sufficient to weaken the signal transmission from the transmembrane domains. Our data provide a biochemical evidence underlying the importance of the polar relay and its network in regulating the catalytic activity of ABCG5/G8 sterol transporter.

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Pathogenic Mechanisms Underlying Stargardt Macular Degeneration Linked to Mutations in the Transmembrane Domains of ABCA4

10.1101/2020.08.28.272914 ◽

2020 ◽

Author(s):

Fabian A. Garces ◽

Jessica F. Scortecci ◽

Robert S. Molday

Keyword(s):

Atpase Activity ◽

Protein Misfolding ◽

Substrate Binding ◽

Transmembrane Domains ◽

Missense Mutations ◽

Loss Of Function ◽

Stargardt Disease ◽

Photoreceptor Outer Segments ◽

Novel Treatments ◽

Stargardt Macular Degeneration

AbstractABCA4 is an ATP-binding cassette (ABC) transporter predominantly expressed in photoreceptors where it transports the substrate N-retinylidene-phosphatidylethanolamine across disc membranes thereby facilitating the clearance of retinal compounds from photoreceptor outer segments. Loss of function mutations in ABCA4 cause the accumulation of bisretinoids leading to Stargardt disease (STGD1) and other retinopathies. In this study, we examined the expression and functional properties of ABCA4 harboring disease-causing missense mutations in the two transmembrane domains (TMDs) of ABCA4. Our results indicate that these mutations lead to protein misfolding, loss in substrate binding, decreased ATPase activity or a combination of these properties. Additionally, we identified an arginine (R653) in transmembrane segment 2 of ABCA4 as a residue essential for substrate binding and substrate-stimulated ATPase activity. The expression and functional activity of the TMD variants correlate well with the severity of STGD1. Our studies provide a basis for developing and evaluating novel treatments for STGD1.

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