An ovine hepatorenal fibrocystic model of a Meckel-like syndrome associated with dysmorphic primary cilia and TMEM67 mutations

• Published in: Scientific reports Vol. 7; no. 1; pp. 1601 - 15
• Main Authors: Stayner, C., Poole, C. A., McGlashan, S. R., Pilanthananond, M., Brauning, R., Markie, D., Lett, B., Slobbe, L., Chae, A., Johnstone, A. C., Jensen, C. G., McEwan, J. C., Dittmer, K., Parker, K., Wiles, A., Blackburne, W., Leichter, A., Leask, M., Pinnapureddy, A., Jennings, M., Horsfield, J. A., Walker, R. J., Eccles, M. R.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09-05-2017; Nature Publishing Group; Nature Portfolio
• Subjects: 13; 13/106; 14; 14/1; 45; 631/208/2489; 64; 64/116; 692/308/1426; 82; 82/51; 82/80; 96/63; Abnormalities, Multiple - genetics; Abnormalities, Multiple - pathology; Amino Acid Substitution; Animal models; Animals; Base Sequence; Chromosomes, Mammalian - genetics; Cilia; Cilia - pathology; Cysts; Dandy-Walker Syndrome - genetics; Dandy-Walker Syndrome - pathology; Disease Models, Animal; Epithelial cells; Epithelial Cells - metabolism; Fibroblasts; Fibrosis; Genetic Loci; Golgi Apparatus - metabolism; Hepatorenal Syndrome - genetics; Hepatorenal Syndrome - pathology; Homozygote; Humanities and Social Sciences; Immunoblotting; Immunofluorescence; Kidney - pathology; Kidneys; Liver; Meckel's syndrome; Membrane Proteins - chemistry; Membrane Proteins - genetics; Morphology; multidisciplinary; Mutation; Mutation - genetics; Mutation, Missense - genetics; Pancreatic Cyst - genetics; Pancreatic Cyst - pathology; Polydactyly; RNA, Messenger - genetics; RNA, Messenger - metabolism; Science; Science (multidisciplinary); Sheep; Zebrafish
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-01519-4

Meckel syndrome (MKS) is an inherited autosomal recessive hepatorenal fibrocystic syndrome, caused by mutations in
TMEM67
, characterized by occipital encephalocoele, renal cysts, hepatic fibrosis, and polydactyly. Here we describe an ovine model of MKS, with kidney and liver abnormalities, without polydactyly or occipital encephalocoele. Homozygous missense p.(Ile681Asn; Ile687Ser) mutations identified in ovine
TMEM67
were pathogenic in zebrafish phenotype rescue assays. Meckelin protein was expressed in affected and unaffected kidney epithelial cells by immunoblotting, and in primary cilia of lamb kidney cyst epithelial cells by immunofluorescence. In contrast to primary cilia of relatively consistent length and morphology in unaffected kidney cells, those of affected cyst-lining cells displayed a range of short and extremely long cilia, as well as abnormal morphologies, such as bulbous regions along the axoneme. Putative cilia fragments were also consistently located within the cyst luminal contents. The abnormal ciliary phenotype was further confirmed in cultured interstitial fibroblasts from affected kidneys. These primary cilia dysmorphologies and length control defects were significantly greater in affected cells compared to unaffected controls. In conclusion, we describe abnormalities involving primary cilia length and morphology in the first reported example of a large animal model of MKS, in which we have identified
TMEM67
mutations.