在小鼠发育过程中线粒体基因组新型R环的表达

The Expression of a Novel R-loop in Mouse Mitochondrial DNA during Developmental Phase

本实验室在成年小鼠线粒体DNA(mtDNA)D环上发现了一个新颖的轻链RNA转录本,这个RNA能够同DNA双链结合,形成一个稳定的DNA-RNA杂合结构(R环)。在此基础上,利用RT-PCR和Northern印迹法检测了小鼠线粒体基因组中R环的时空表达的特点。发现R环在小鼠不同组织、不同发育阶段中的表达水平有差异,其表达模式具有分化的位相性和时序性,提示R环有可能作为参与调控线粒体基因表达的分子,因而具有重要意义。

A novel RNA species that is coded by and complementary to heavy-strand at the mtDNA D-loop region combines with DNA double strand, forming a stable DNA-RNA hybrid （R-loop） spanning the whole H-strand of D-loop region in mouse mtDNA. In this study, we detected the temporal-spatial expression pattern of R-loop in mouse mitochondrion by RT-PCR and Northern blot. An age-dependent increase of R-loop and the differences of R-loop among tissues were found. The differential spatial and temporal expression pattern of R-loop indicates that the biological function of R-loop might be a regulator to control mitochondrial genome expression.