ABSTRACT
Leprosy, a chronic infectious disease caused by Mycobacterium leprae (M. leprae), was very common in Europe till the 16th century. Here, we perform an ancient DNA study on medieval skeletons from Denmark that show lesions specific for lepromatous leprosy (LL). First, we test the remains for M. leprae DNA to confirm the infection status of the individuals and to assess the bacterial diversity. We assemble 10 complete M. leprae genomes that all differ from each other. Second, we evaluate whether the human leukocyte antigen allele DRB1*15:01, a strong LL susceptibility factor in modern populations, also predisposed medieval Europeans to the disease. The comparison of genotype data from 69 M. leprae DNA-positive LL cases with those from contemporary and medieval controls reveals a statistically significant association in both instances. In addition, we observe that DRB1*15:01 co-occurs with DQB1*06:02 on a haplotype that is a strong risk factor for inflammatory diseases today.
Subject(s)
DNA, Ancient , Genetic Predisposition to Disease , Leprosy/genetics , White People/genetics , DNA, Bacterial/genetics , Denmark , Fossils , Genome, Bacterial , HLA-DQ beta-Chains/genetics , HLA-DRB1 Chains/genetics , High-Throughput Screening Assays , Humans , Mycobacterium leprae/geneticsABSTRACT
Hypertension is one of the major risk factors for chronic kidney disease. Using quantitative trait loci analysis, we identified the gene of the F-BAR protein NOSTRIN in the center of an overlapping region in rat and human quantitative trait loci that are associated with hypertension. Immunohistochemical analysis revealed a predominantly podocytic expression pattern of NOSTRIN in human and mouse glomeruli. Further, NOSTRIN colocalizes with cell-cell contact-associated proteins ß-catenin and zonula occludens-1 and interacts with the slit-membrane-associated adaptor protein CD2AP. In zebrafish larvae, knockdown of nostrin alters the glomerular filtration barrier function, inducing proteinuria and leading to ultrastructural morphological changes on the endothelial and epithelial side and of the glomerular basement membrane of the glomerular capillary loop. We conclude that NOSTRIN expression is an important factor for the integrity of the glomerular filtration barrier. Disease-related alteration of NOSTRIN expression may not only affect the vascular endothelium and, therefore, contribute to endothelial cell dysfunction but might also contribute to the development of podocyte disease and proteinuria.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Glomerular Basement Membrane/physiopathology , Hypertension/genetics , Kidney Glomerulus/physiopathology , Membrane Proteins/genetics , Adaptor Proteins, Signal Transducing/metabolism , Animals , Glomerular Basement Membrane/metabolism , Glomerular Basement Membrane/ultrastructure , Hypertension/metabolism , Hypertension/physiopathology , Kidney Glomerulus/metabolism , Kidney Glomerulus/ultrastructure , Membrane Proteins/metabolism , Podocytes/metabolism , Proteinuria/genetics , Proteinuria/metabolism , Proteinuria/physiopathology , ZebrafishABSTRACT
Gene array-type experiments have identified large numbers of genes thought to be important for the integrity of the glomerular slit diaphragm. Confirmation of individual proteins has been limited by the expenses and time involved in generating transgenic or knockout mice for each candidate. We present a functional screening assay based on the clearance of a 70-kDa fluorescent dextran in another vertebrate system that is rapid and low in cost. In the pronephric glomerulus of larval zebrafish, we have demonstrated quantifiable loss of slit diaphragm integrity in a zebrafish model of puromycin aminonucleoside (PA) toxicity. In addition, after knockdown of CD2-associated protein (CD2AP) and podocin, two well-characterized genetic contributors to podocyte differentiation in mammals, we observed glomerular loss of serum macromolecules similar to that seen in mammalian kidneys with inborn mutations in these genes. Increased filtration of 70-kDa FITC-labeled dextran correlates with effacement of podocyte foot processes in ultrastructural analysis. These findings document the value of the zebrafish model in genomics and pharmacological screening applications.
