The number of the CTCF binding sites of the H19/IGF2:IG-DMR correlates with DNA methylation and expression imprinting in a humanized mouse model.
The number of the CTCF binding sites of the H19/IGF2:IG-DMR correlates with DNA methylation and expression imprinting in a humanized mouse model.
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DOI：
10.1093/hmg/ddab132
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发表时间：
2021-07-28
影响因子：
3.5
通讯作者：
Cerrato F
中科院分区：
文献类型：
--
作者：
Freschi A;Del Prete R;Pignata L;Cecere F;Manfrevola F;Mattia M;Cobellis G;Sparago A;Bartolomei MS;Riccio A;Cerrato F
H19和IGF 2的来源特异性表达的互亲由H19/IGF 2：IG-DMR（IC 1）控制，其母体等位基因未甲基化并充当CTCF依赖性绝缘子。在人类中，内部IC 1缺失与Beckwith-Wiedemann综合征（BWS）和Silver-Russell综合征（SRS）相关，这取决于其父母来源。这些基因突变导致DNA甲基化异常、IGF 2/H19失调和不完全转化的疾病。然而，微缺失与改变的分子和临床表型之间的联系机制仍不清楚。为了解决这一问题，我们先前已经产生并表征了两个敲入小鼠品系，其中人类野生型（hIC 1 wt）或突变型（hIC 1 + 2.2）IC 1等位基因取代了内源性小鼠IC 1（mIC 1）。在这里，我们报告了一个额外的敲入线携带突变hIC 1等位基因与内部1.8 kb的缺失（hIC 1 → 1.8）。这些小鼠的表型不同于携带hIC 1 β 2.2的小鼠，部分类似于hIC 1 wt动物。事实上，在hIC 1 Δ1.8的母体传递的小鼠中，适当的H19和Igf 2印迹和正常生长表型是明显的，而低DNA甲基化和非存活表型是其父系传递的特征。与hIC 1 wt相反，父系遗传hIC 1 Δ1.8的E15.5胚胎显示多样化的hIC 1甲基化。此外，在三分之一的小鼠中发现了与体重增加相关的Igf 2表达增加。在携带三种不同hIC 1等位基因的小鼠胚胎干细胞中进行的染色质免疫沉淀实验表明，CTCF靶位点的数量影响其与hIC 1的结合，这表明在小鼠中，CTCF结合是确定hIC 1甲基化和Igf 2表达的关键。
The reciprocal parent of origin-specific expression of H19 and IGF2 is controlled by the H19/IGF2:IG-DMR (IC1), whose maternal allele is unmethylated and acts as a CTCF-dependent insulator. In humans, internal IC1 deletions are associated with Beckwith–Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS), depending on their parental origin. These genetic mutations result in aberrant DNA methylation, deregulation of IGF2/H19 and disease with incomplete penetrance. However, the mechanism linking the microdeletions to altered molecular and clinical phenotypes remains unclear. To address this issue, we have previously generated and characterized two knock-in mouse lines with the human wild-type (hIC1wt) or mutant (hIC1∆2.2) IC1 allele replacing the endogenous mouse IC1 (mIC1). Here, we report an additional knock-in line carrying a mutant hIC1 allele with an internal 1.8 kb deletion (hIC1∆1.8). The phenotype of these mice is different from that of the hIC1∆2.2-carrying mice, partially resembling hIC1wt animals. Indeed, proper H19 and Igf2 imprinting and normal growth phenotype were evident in the mice with maternal transmission of hIC1Δ1.8, while low DNA methylation and non-viable phenotype characterize its paternal transmission. In contrast to hIC1wt, E15.5 embryos that paternally inherit hIC1Δ1.8 displayed variegated hIC1 methylation. In addition, increased Igf2 expression, correlating with increased body weight, was found in one third of these mice. Chromatin immunoprecipitation experiments in mouse embryonic stem cells carrying the three different hIC1 alleles demonstrate that the number of CTCF target sites influences its binding to hIC1, indicating that in the mouse, CTCF binding is key to determining hIC1 methylation and Igf2 expression.
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影响因子：
3.5
作者：
Beygo J;Citro V;Sparago A;De Crescenzo A;Cerrato F;Heitmann M;Rademacher K;Guala A;Enklaar T;Anichini C;Cirillo Silengo M;Graf N;Prawitt D;Cubellis MV;Horsthemke B;Buiting K;Riccio A
通讯作者：
Riccio A
影响因子：
30.8
作者：
Sparago, A;Cerrato, F;Riccio, A
通讯作者：
Riccio, A
影响因子：
3.5
作者：
Cerrato, F;Sparago, A;Riccio, A
通讯作者：
Riccio, A
影响因子：
64.8
作者：
Hark, AT;Schoenherr, CJ;Tilghman, SM
通讯作者：
Tilghman, SM
影响因子：
3.5
作者：
Sparago, Angela;Russo, Silvia;Riccio, Andrea
通讯作者：
Riccio, Andrea