Fu Ye, Luo Guan-Zheng, Chen Kai, Deng Xin, Yu Miao, Han Dali, Hao Ziyang, Liu Jianzhao, Lu Xingyu, Dore Louis C, Weng Xiaocheng, Ji Quanjiang, Mets Laurens, He Chuan
Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA.
Howard Hughes Medical Institute, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA.
Cell. 2015 May 7;161(4):879-892. doi: 10.1016/j.cell.2015.04.010. Epub 2015 Apr 30.
N(6)-methyldeoxyadenosine (6mA or m(6)A) is a DNA modification preserved in prokaryotes to eukaryotes. It is widespread in bacteria and functions in DNA mismatch repair, chromosome segregation, and virulence regulation. In contrast, the distribution and function of 6mA in eukaryotes have been unclear. Here, we present a comprehensive analysis of the 6mA landscape in the genome of Chlamydomonas using new sequencing approaches. We identified the 6mA modification in 84% of genes in Chlamydomonas. We found that 6mA mainly locates at ApT dinucleotides around transcription start sites (TSS) with a bimodal distribution and appears to mark active genes. A periodic pattern of 6mA deposition was also observed at base resolution, which is associated with nucleosome distribution near the TSS, suggesting a possible role in nucleosome positioning. The new genome-wide mapping of 6mA and its unique distribution in the Chlamydomonas genome suggest potential regulatory roles of 6mA in gene expression in eukaryotic organisms.
N⁶-甲基脱氧腺苷（6mA或m⁶A）是一种从原核生物到真核生物都保留的DNA修饰。它在细菌中广泛存在，并在DNA错配修复、染色体分离和毒力调节中发挥作用。相比之下，6mA在真核生物中的分布和功能尚不清楚。在这里，我们使用新的测序方法对衣藻基因组中的6mA图谱进行了全面分析。我们在衣藻84%的基因中鉴定出了6mA修饰。我们发现，6mA主要位于转录起始位点（TSS）周围的ApT二核苷酸处，呈双峰分布，似乎标记着活跃基因。在碱基分辨率下也观察到了6mA沉积的周期性模式，这与TSS附近的核小体分布有关，表明其在核小体定位中可能发挥作用。新的全基因组6mA图谱及其在衣藻基因组中的独特分布表明，6mA在真核生物基因表达中具有潜在的调节作用。
