The Construction Of MPL Syndrome Rabbit Model Using CRISPR/Cas9

A novel fibrillinopathy,named Marfanoid-progeroid-lipodystrophy syndrome(MPL),has been reported in the clinic.All MPL patients carry mutations in exon 65 of FBN1 gene,which leads to a premature stop codon in the C-terminus.The FBN1 gene(Gene ID: 100350931),which located in chromosome 15,consists of 66 exons and comprises 7 main protein domains.Moreover,the FBN1 gene,which encodes fibrillin-1,is a major component of 10-12 nm diameter microfibrils.These microfibrils are found in the periphery of elastic fibers and elastin-free bundles,including the ciliary zonule,the elastic fibers in connective tissue.Different mutations in the FBN1 gene lead to a wide range of phenotypes,such as Marfan syndrome(MFS),Weill–Marchesani syndrome(WMS),and Stiff Skin syndrome(SSS).To date,more than 1847 different mutations of fibrillin-1 have been reported in UMD-FBN1 mutations database(http://www.umd.be/FBN1/).Thus,various FBN1 knockout(KO),or dominant negative mutant mice are widely used as an animal model,such as mg N,mg R,mg?,WM?,H1?,C1039 G.However,these mouse models did not fully summarize the phenotype and genotype of MPL syndrome.In order to study pathogenesis and drug screening for MPL syndrome,we describe the generation of a rabbit MPL model with C-terminal truncation of fibrillin-1 using a CRISPR/Cas9 system.Firstly,we obtained the rabbit MPL model,which was mated with wild-type rabbits.Thus,the F1 FBN1 Heterozygous(FBN1 Het)rabbits were obtained.Secondly,we have described the phenotypes of FBN1 Het rabbits.The FBN1 Het rabbits faithfully recapitulated the phenotypes of MFS,including muscle wasting and impaired connective tissue,ocular syndrome and aortic dilation.Moreover,skin symptoms,lipodystrophy,growth retardation and dysglycemia were also seen in these FBN1 Het rabbits,which were not been reported in other animal models.In conclusion,this novel rabbit model mimics the histopathological changes and functional defects of MPL syndrome and may become a valuable model for studies of pathogenesis and drug screening for MPL syndrome.