DNA methylation is an essential epigenetic modification, and found to be dynamically changed due to the ob- servation of active DNA demethylation. During active demethylation, 5-methylcytosine （5mC） was oxidized ste...DNA methylation is an essential epigenetic modification, and found to be dynamically changed due to the ob- servation of active DNA demethylation. During active demethylation, 5-methylcytosine （5mC） was oxidized step- wise by ten-eleven translocation （TET） enzymes into 5-hydroxymethylcytosine （5hmc）, 5-formylcytosine （5fC）, and 5-carboxylcytosine （5caC）. Then, the subsequent excision of 5fC and 5caC combined with base excision repair further restored cytosine, which completes the demethylation process. Here, we report that 5-formylcytosine and 5-carboxylcytosine significantly reduce the activity of HhaI DNA methyltransferase to methylate target cytosines when present on the hemi-modified sequence of the complementary DNA. This finding demonstrates that 5fC and 5caC function as more than intermediates for active DNA demethylation.展开更多
基金This work was supported by the Major Program of National Natural Science Foundation of China （No. 21334005）, the National Natural Science Foundation of China （Nos. 21304021 and 21432008）, and the National Basic Research Program of China （Nos. 2010CB732203 and 2012CB720603）.
文摘为了解决高温度或长反应的问题，在碳点(CD ) 的热水的合成预定，一个新奇方法基于支持的碳化由盐酸催化作用在现在的工作被开发的酸。催化的碳点的酸(ACD ) 在 200 虪箳椰嬑郢 G
文摘DNA methylation is an essential epigenetic modification, and found to be dynamically changed due to the ob- servation of active DNA demethylation. During active demethylation, 5-methylcytosine （5mC） was oxidized step- wise by ten-eleven translocation （TET） enzymes into 5-hydroxymethylcytosine （5hmc）, 5-formylcytosine （5fC）, and 5-carboxylcytosine （5caC）. Then, the subsequent excision of 5fC and 5caC combined with base excision repair further restored cytosine, which completes the demethylation process. Here, we report that 5-formylcytosine and 5-carboxylcytosine significantly reduce the activity of HhaI DNA methyltransferase to methylate target cytosines when present on the hemi-modified sequence of the complementary DNA. This finding demonstrates that 5fC and 5caC function as more than intermediates for active DNA demethylation.
