|
|
![]() |
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Research Article |
Department of Molecular Cell Biology, Laboratory for Cytochemistry and Cytometry, Leiden University Medical Center, Wassenaarseweg 72, 2333 AL Leiden, The Netherlands
Corresponding author (e-mail: R.W.Dirks{at}lumc.nl)
Accepted October 12, 2001
Compelling evidence supports an intimate link in time and space between eukaryotic pre-mRNA synthesis and processing and nucleocytoplasmic transport of mature mRNA. In this study, we analyzed the kinetic behavior of these processes in a quantitative manner. We used FISH and confocal scanning laser microscopy to detect transcripts produced by an inducible human cytomegalovirus immediate early (HCMV-IE) expression system. Upon induction, a large amount of pre-mRNA accumulated in nuclear foci at or near their transcription sites and, at later time, throughout the nucleoplasm. Inhibition of RNA polymerase II activity resulted in a rapid decrease in the number of transcripts in the nuclear RNA foci (half time
two minutes), indicating that accumulated transcripts were rapidly spliced and then released. The dispersed nucleoplasmic transcripts exited the nucleus with a half time of
10 minutes. Both processes were temperature dependent, suggesting that mRNA export is an active process. RNA polymerase II activation revealed that production of mature HCMV IE mRNAs required less than five minutes. Transcripts radiated from the gene at an average speed of
0.13 µm2/sec from this time on. Thus, it appears that these processes are tightly linked in time and space, with the splicing reaction as a rate-limiting factor.
Key words: Fluorescent in situ hybridization, Confocal scanning laser microscopy, RNA polymerase II, Human cytomegalovirus
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
This article has been cited by other articles:
![]() |
C. Molenaar, A. Abdulle, A. Gena, H. J. Tanke, and R. W. Dirks Poly(A)+ RNAs roam the cell nucleus and pass through speckle domains in transcriptionally active and inactive cells J. Cell Biol., April 26, 2004; 165(2): 191 - 202. [Abstract] [Full Text] [PDF] |
||||