NT5E mutations and arterial calcifications.
NT5E mutations and arterial calcifications.
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DOI：
10.1056/nejmoa0912923
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发表时间：
2011-02-03
期刊：
影响因子：
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通讯作者：
Boehm M
中科院分区：
文献类型：
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作者：
St Hilaire C;Ziegler SG;Markello TC;Brusco A;Groden C;Gill F;Carlson-Donohoe H;Lederman RJ;Chen MY;Yang D;Siegenthaler MP;Arduino C;Mancini C;Freudenthal B;Stanescu HC;Zdebik AA;Chaganti RK;Nussbaum RL;Kleta R;Gahl WA;Boehm M
动脉钙化与心血管风险增加相关，但这种关联的遗传基础尚不清楚。我们对三个患有症状性动脉钙化的家庭进行了临床、影像学和遗传学研究。进行单核苷酸多态性分析、靶向基因测序、定量聚合酶链反应测定、Western印迹、酶测量、转导拯救实验和体外钙化测定。我们确定了9名下肢动脉和手足关节囊钙化的患者：一个家庭的所有5名兄弟姐妹，另一个家庭的3名兄弟姐妹，第三个家庭的1名患者。血清钙、磷酸盐和维生素D水平正常。家族1的受影响成员在6号染色体上共享单一的22.4 Mb纯合性区域，并在NT5E中具有纯合无义突变（c.662C→A，p.S221X），编码CD73，将AMP转化为腺苷。家族2的受影响成员在NT5E中存在纯合错义突变（c.1073G→A，p.C358Y）。家系3的先证者为c.662C→A和c.1609dupA（p.V537fsX7）复合杂合子。在这三个家族中发现的所有突变都会导致无功能的CD73。培养的成纤维细胞从受影响的家庭成员1表现出显着降低表达的NT5E信使RNA，CD73蛋白，和酶的活性，以及增加碱性磷酸酶水平和积累的磷酸钙晶体。基因拯救实验使患者细胞中的CD73和碱性磷酸酶活性正常化，腺苷治疗降低了碱性磷酸酶和钙化的水平。我们在三个有症状的动脉和关节钙化的家族成员中鉴定了NT5E突变。该基因编码CD73，其将AMP转化为腺苷，支持该代谢途径在抑制异位组织钙化中的作用。（由美国国家人类基因组研究所和美国国立卫生研究院国家心脏，肺和血液研究所资助。
Arterial calcifications are associated with increased cardiovascular risk, but the genetic basis of this association is unclear. We performed clinical, radiographic, and genetic studies in three families with symptomatic arterial calcifications. Single-nucleotide-polymorphism analysis, targeted gene sequencing, quantitative polymerase-chain-reaction assays, Western blotting, enzyme measurements, transduction rescue experiments, and in vitro calcification assays were performed. We identified nine persons with calcifications of the lower-extremity arteries and hand and foot joint capsules: all five siblings in one family, three siblings in another, and one patient in a third family. Serum calcium, phosphate, and vitamin D levels were normal. Affected members of Family 1 shared a single 22.4-Mb region of homozygosity on chromosome 6 and had a homozygous nonsense mutation (c.662C→A, p.S221X) in NT5E, encoding CD73, which converts AMP to adenosine. Affected members of Family 2 had a homozygous missense mutation (c.1073G→A, p.C358Y) in NT5E. The proband of Family 3 was a compound heterozygote for c.662C→A and c.1609dupA (p.V537fsX7). All mutations found in the three families result in nonfunctional CD73. Cultured fibroblasts from affected members of Family 1 showed markedly reduced expression of NT5E messenger RNA, CD73 protein, and enzyme activity, as well as increased alkaline phosphatase levels and accumulated calcium phosphate crystals. Genetic rescue experiments normalized the CD73 and alkaline phosphatase activity in patients’ cells, and adenosine treatment reduced the levels of alkaline phosphatase and calcification. We identified mutations in NT5E in members of three families with symptomatic arterial and joint calcifications. This gene encodes CD73, which converts AMP to adenosine, supporting a role for this metabolic pathway in inhibiting ectopic tissue calcification. (Funded by the National Human Genome Research Institute and the National Heart, Lung, and Blood Institute of the National Institutes of Health.)