학술논문

COPA mutations impair ER-Golgi transport and cause hereditary autoimmune-mediated lung disease and arthritis
Document Type
article
Source
Nature Genetics. 47(6)
Subject
Biochemistry and Cell Biology
Biological Sciences
Autoimmune Disease
Lung
Arthritis
Genetics
2.1 Biological and endogenous factors
Aetiology
Inflammatory and immune system
Amino Acid Sequence
Autoimmune Diseases
Child
Preschool
Coatomer Protein
Endoplasmic Reticulum
Endoplasmic Reticulum Stress
Female
Genetic Association Studies
Genetic Predisposition to Disease
Golgi Apparatus
HEK293 Cells
Humans
Infant
Lod Score
Lung Diseases
Interstitial
Male
Molecular Sequence Data
Pedigree
Protein Transport
Baylor-Hopkins Center for Mendelian Genomics
Medical and Health Sciences
Developmental Biology
Agricultural biotechnology
Bioinformatics and computational biology
Language
Abstract
Unbiased genetic studies have uncovered surprising molecular mechanisms in human cellular immunity and autoimmunity. We performed whole-exome sequencing and targeted sequencing in five families with an apparent mendelian syndrome of autoimmunity characterized by high-titer autoantibodies, inflammatory arthritis and interstitial lung disease. We identified four unique deleterious variants in the COPA gene (encoding coatomer subunit α) affecting the same functional domain. Hypothesizing that mutant COPA leads to defective intracellular transport via coat protein complex I (COPI), we show that COPA variants impair binding to proteins targeted for retrograde Golgi-to-ER transport. Additionally, expression of mutant COPA results in ER stress and the upregulation of cytokines priming for a T helper type 17 (TH17) response. Patient-derived CD4(+) T cells also demonstrate significant skewing toward a TH17 phenotype that is implicated in autoimmunity. Our findings uncover an unexpected molecular link between a vesicular transport protein and a syndrome of autoimmunity manifested by lung and joint disease.