Factors related to RNA polymerase II transcription are localized in interchromatin granule clusters of Panorpa communis oocytes.

Diplotene oocyte nucleus of the scorpionfly Panorpa communis is transcriptionally silent and contains numerous nuclear bodies including interchromatin granule clusters (IGCs). The latter consist of the granules of 30-50 nm in diameter and contain IGC marker protein SC35 as well as RNA polymerase II. In this study, we also localized in P. communis oocyte IGCs the transcription coactivators CBP/p300, TATA-binding protein (TBP) which is a component of the basal transcription factor TFIID and the basal transcription factor TFIIH. We belive that IGCs in transcriptionally inert P. communis oocytes are storage sites for the components of RNA polymerase II holoenzyme and other factors of RNA pol II transcription.