De novo variant in RING finger protein 213 causes systemic vasculopathy.

Systemic arterial stenosis, including moyamoya disease (MMD) and middle aortic syndrome (MAS), is a rare condition of unclear etiology. MMD is a cerebral angiopathy, whereas MAS affects abdominal and thoracic aortas, leading to various complications. Although some genetic associations with MAS have been identified, the causes remain elusive. In this study, whole-exome sequencing was used to identify de novo heterozygous missense variants of RING finger protein 213 (RNF213) (p.His4058Pro and p.Thr4155Pro) in two unrelated families exhibiting both MAS and MMD. To understand the significance of these variants, we generated knockin mice carrying the Rnf213 p.His4058Pro variant. Notably, homozygous knockin mice exhibited perinatal lethality due to respiratory failure and lung dysplasia, suggesting that this variant is pathogenic. Lung dysplasia in homozygous knockin mice was associated with upregulated innate immunity and inflammatory responses and downregulated cell proliferation. The findings suggested that in mice, the RNF213 p.His4058Pro variant plays critical roles in lung development, innate immunity, and inflammation, revealing the complexity of RNF213 function in various tissues and species. In conclusion, this study provides insights into the genetic basis of MAS and MMD, highlights the potential involvement of RNF213 variants in systemic vasculopathy, and identifies unexpected associations with lung development and immune processes. To investigate the effect of the de novo variant in RING finger protein 213, we generated the the Rnf213 knockin (KI) mouse model carrying a heterozygous variant by CRISPR-Cas9 genome editing. We found that homozygote KI mice had perinatal lethality due to respiratory failure and had disorganized lung structure.whereas heterozygote KI mice grew normally. We then performed gene expression profiling analysis of RNA-seq data of the lung from E18.5 KI mice. Comparative gene expression profiling analysis of RNA-seq data between wildtype, heterozygote knock-in, and homozygote knock-in mice.系统性动脉狭窄包括烟雾病（moyamoya disease, MMD）与主动脉中部综合征（middle aortic syndrome, MAS），是一类病因不明的罕见疾病。其中MMD属于脑血管病变，而MAS可累及胸主动脉与腹主动脉，引发多种并发症。尽管已有研究发现MAS与部分遗传因素存在关联，但其具体致病机制仍不明确。本研究通过全外显子组测序（whole-exome sequencing），在两例同时罹患MAS与MMD的无亲缘关系家系中，鉴定出环指蛋白213（RING finger protein 213, RNF213）的新发杂合错义变异（de novo heterozygous missense variants）（p.His4058Pro与p.Thr4155Pro）。为明确上述变异的生物学意义，我们构建了携带Rnf213 p.His4058Pro变异的敲入小鼠模型。值得注意的是，纯合子敲入小鼠会因呼吸衰竭与肺发育异常出现围产期致死现象，提示该变异具有致病性。纯合子敲入小鼠的肺发育异常与先天免疫及炎症反应上调、细胞增殖下调密切相关。本研究结果表明，在小鼠体内，RNF213 p.His4058Pro变异对肺发育、先天免疫与炎症反应均发挥关键调控作用，揭示了RNF213在不同组织与物种中的功能复杂性。综上，本研究为MAS与MMD的遗传基础提供了新见解，强调了RNF213变异在系统性血管病变中的潜在参与作用，并揭示了其与肺发育及免疫进程的意外关联。为探究RNF213新发变异的生物学效应，我们通过CRISPR-Cas9基因组编辑（CRISPR-Cas9 genome editing）技术，构建了携带杂合变异的Rnf213敲入（KI）小鼠模型。研究发现，纯合子KI小鼠会因呼吸衰竭出现围产期致死，且肺组织结构紊乱；而杂合子KI小鼠可正常生长发育。随后我们对E18.5胎龄KI小鼠的肺组织RNA测序（RNA-seq）数据进行了基因表达谱分析，并针对野生型、杂合子敲入及纯合子敲入小鼠的肺组织RNA-seq数据开展了对比基因表达谱分析。