Kloc M
Eur J Cell Biol. 1980 Aug;21(3):328-34.
The participation of extrachromosomal DNA (extra DNA) in RNA synthesis in the nuclei of terminal oogonial cells and oocytes in the pupal ovary of Creophilus maxillosus (Staphylinidae, Coleoptera) was examined by autoradiography. It was found that extra DNA in the nuclei of terminal oogonial cells, although predominantly in a condensed and heterochromatic state, produces numerous nucleoli and incorporates 3H-uridine during the interphases between successive differential divisions. Moreover, it was shown that extra DNA is active in RNA synthesis at the same stage of pupal development in which it is synthesized and accumulated, i.e. in the nuclei of terminal oogonial cells. As soon as the oocyte forms RNA synthesis ceases in the extrachromosomal DNA body cells showed that nucleolar material does not disappear during division but remains, at least partly, connected with the extra DNA body.
通过放射自显影术研究了嗜尸性葬甲（鞘翅目，葬甲科）蛹期卵巢中终末卵原细胞和卵母细胞核内的染色体外DNA（额外DNA）参与RNA合成的情况。研究发现，终末卵原细胞核内的额外DNA虽然主要处于浓缩的异染色质状态，但在连续差异分裂的间期会产生大量核仁并掺入3H-尿苷。此外，研究表明，额外DNA在其合成和积累的蛹期发育同一阶段，即在终末卵原细胞核内，在RNA合成中具有活性。一旦卵母细胞形成，染色体外DNA体细胞中的RNA合成就会停止，这表明核仁物质在分裂过程中不会消失，而是至少部分地与额外DNA体相连。
