Interchromosomal transfer of epigenetic states in Ascobolus: Transfer of DNA methylation is mechanistically related to homologous recombination
Interchromosomal transfer of epigenetic states in Ascobolus: Transfer of DNA methylation is mechanistically related to homologous recombination
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DOI：
10.1016/s0092-8674(00)80161-0
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发表时间：
1996-09-20
期刊：
影响因子：
64.5
通讯作者：
Rossignol, JL
中科院分区：
文献类型：
--
作者：
Colot, V;Maloisel, L;Rossignol, JL
等位基因之间的甲基化转移代表了一种合理的表观遗传突变机制，可以解释哺乳动物中印记的丧失和植物中的副突变。在这里，我们利用真菌 Ascobolus immersus 独特的优势，获得了同源染色体之间可以发生甲基化转移的直接实验证据。 Ascobolus b2 孢子颜色基因的甲基化等位基因和非甲基化等位基因在单个减数分裂细胞中聚集在一起。观察到甲基化频繁转移至未甲基化等位基因。这种转移沿着 b2 基因从 5' 极化到 3'，就像基因转换一样，并且在同一杂交中测试时始终伴随着后一个过程。这些和其他观察结果强烈表明甲基化转移和重组在机制上是相关的。
The transfer of methylation between alleles represents a plausible epigenetic mutational mechanism to explain loss of imprinting in mammals and paramutation in plants. Here, we have exploited advantages unique to the fungus Ascobolus immersus to obtain direct experimental evidence that methylation transfer can occur between homologous chromosomes. A methylated allele and an unmethylated allele of the Ascobolus b2 spore color gene were brought together in individual meiotic cells. Frequent transfer of methylation to the unmethylated allele was observed. This transfer was polarized 5' to 3' along the b2 gene, as is gene conversion, and always accompanied the latter process when tested in the same cross. These and other observations strongly suggest that methylation transfer and recombination are mechanistically related.