PubMed ID

1720123

UMMS Affiliation

Department of Cell Biology

Date

12-1-1991

Document Type

Article

Subjects

Antigens; Cell Nucleus; Cells, Cultured; Fluorescent Antibody Technique; Humans; Male; Mitosis; Poly A; RNA; Ribonucleoproteins; Ribonucleoproteins, Small Nuclear; Transcription, Genetic

Disciplines

Cell Biology | Life Sciences | Medicine and Health Sciences

Abstract

The functional organization of the nucleus was studied using a fluorescence microscopy approach which allowed integration of positional information for RNA, DNA, and proteins. In cells from sea urchin to human, nuclear poly(A) RNA was found concentrated primarily within several discrete "transcript domains" which often surrounded nucleoli. Concentrations of poly(A) RNA were coincident with snRNP antigen clusters, providing evidence for the localization of pre-mRNA splicing at these sites. The spatial relationship of transcript domains with respect to various classes of DNA was established, in that the poly(A) RNA-rich regions coincided with discrete regions of low DNA density and were non-randomly distributed with respect to specific DNA sequences. Centromeric DNA and late-replicating DNA did not overlap transcript domains, whereas a subset of early-replicating DNA may. Results indicate that transcript domains do not result directly from a simple clustering of chromatin corresponding to metaphase chromosomes bands. Finally, observations on the reassembly of these domains after mitosis suggest that the clustering of snRNP antigens may be dependent on the reappearance of pol II transcription. Implications of these findings for overall nuclear structure and function are considered, including a discussion of whether transcript domains may be sites of polymerase II transcription reflecting a clustering of active genes.

Rights and Permissions

Citation: J Cell Biol. 1991 Dec;115(5):1191-202. Link to article on publisher's website

Related Resources

Link to Article in PubMed

 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.