Unknown,Transcriptomics,Genomics,Proteomics

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Jag1K295*/+ as a mouse model for Alagille syndrome

ABSTRACT: A new mouse mutant was identified at the Munich ENU mutagenesis project due to hyperactivity, head tossing, and circling behaviour. Neurological and gross morphological phenotyping of these mutant mice revealed impairment of the vestibular system. Using whole genome exome sequencing and a custom-made variant calling pipeline, we identified the causative mutation as an A->T substitution on the chromosome 2 at the position 128 in the exon 6 of jagged 1 (Jag1) gene. This introduces a premature termination codon at the position 883 of the cDNA. In humans, mutations in the JAG1 gene are associated with Alagille syndrome (ALGS1 ), a multisystem developmental disorder mainly affecting small bile ducts in the liver, but also heart, skeleton, and eyes, and occasionally also kidney or inner ears. Further examination of the Jag1K295*/+ mutant mouse line disclosed multiorgan deficiencies, such as cardiac liver congestion, bile duct hypoplasia, mild nephropathy, subvalvular hypertrophy of the right ventricle, and mild growth retardation. No skeletal abnormalities could be detected. In summary, we report a novel mouse model for Alagille syndrome, Jag1K295*/+, which resembles most of the features of the mild form of Alagille syndrome observed in patients. Total RNA obtained from liver of 4 male heterozygous Jag1K295*/+ and 4 male wildtype mice

ORGANISM(S): Mus musculus

SUBMITTER: Marion Horsch

PROVIDER: E-GEOD-55602 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Jag1K295*/+ as a mouse model for Alagille syndrome

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