Nuclear distribution of RNA polymerase II in human oocytes from antral follicles: Dynamics relative to the transcriptional state and association withsplicing factors

Citation
Vn. Parfenov et al., Nuclear distribution of RNA polymerase II in human oocytes from antral follicles: Dynamics relative to the transcriptional state and association withsplicing factors, J CELL BIOC, 77(4), 2000, pp. 654-665
Citations number
58
Categorie Soggetti
Cell & Developmental Biology
Journal title
JOURNAL OF CELLULAR BIOCHEMISTRY
ISSN journal
07302312 → ACNP
Volume
77
Issue
4
Year of publication
2000
Pages
654 - 665
Database
ISI
SICI code
0730-2312(200004)77:4<654:NDORPI>2.0.ZU;2-6
Abstract
The intranuclear distribution of two (unphosphorylated and hyperphosphoryla ted) forms of RNA polymerase II (Pol II) was studied in human oocytes from antral follicles using immunogold labeling/electron microscopy. The distrib ution of Pol II was analyzed relative to the transcriptional state of the o ocyte as well as to the distribution of two splicing factors (snRNPs and SC -35) in the intranuclear entities, namely, interchromatin granule clusters (IGCs), nucleolus-like bodies (NLBs), and perichromatin fibrils (PFs). The results showed that (1) antibodies directed against two forms of Pol II hav e similar pattern of intranuclear distribution, (2) both Pal II and splicin g factors progressively accumulate in IGCs with decrease in the transcripti onal activity of the oocyte nucleus, (3) both Pol II and splicing factors l ocalize to PFs, and (4) Pol II is present in the NLBs at all transcriptiona l states of the oocyte nucleus. These studies confirm earlier proposals tha t PFs represent a nuclear domain in which RNA transcription/processing are spatially coupled. The accumulation of Pol II and splicing factors in IGCs concomitant with a decrease in the transcriptional activity suggests a coor dinated mechanism for the movement of both Pol II and splicing factors from the sites of action to the sites of storage, J. Cell. Biochem. 77:654-665, 2000. (C) 2000 Wiley-Liss, Inc.