The electron microscopy assay shows that angiogenin was located in DFCs, where rDNA was mainly situated and the synthesis of rRNA took place.

• 进一步的免疫透射电镜实验分析表明血管生成素进入细胞核后，其在核仁的分布与rDNA的分布及rRNA 的合成区域相同，可能其作用与rDNA相关。