Localization of nascent RNA and CREB binding protein with the PML-containing nuclear body

Localization of nascent RNA and CREB binding protein with the PML-containing nuclear body

^*Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, CA 92037; and ^¶Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037

Contributed by Ronald M. Evans

Abstract

The cellular role of the PML-containing nuclear bodies also known as ND10 or PODs remains elusive despite links to oncogenesis and viral replication. Although a potential role in transcription has been considered, direct evidence has been lacking. By developing a novel in vivo nucleic acid labeling approach, we demonstrate the existence of nascent RNA polymerase II transcripts within this nuclear body. In addition, PML and the transactivation cofactor, CREB binding protein (CBP), colocalize within the nucleus. Furthermore, we show that CBP in contrast to PML is distributed throughout the internal core of the structure. Collectively, these findings support a role for this nuclear body in transcriptional regulation.

Footnotes

↵ † Current address: Beckman Laser Institute, Laser Microbeam & Medical Program, University of California, Irvine, CA 92612.
↵ ‡ V.J.L. and J.A.D. contributed equally to this work.
↵ § Current address: Division of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92122.
↵ ‖ To whom reprint requests should be addressed at: The Salk Institute for Biological Studies, Howard Hughes Medical Institute, Gene Expression Laboratory, 10010 North Torrey Pines Road, La Jolla, CA 92037. e-mail: evans{at}salk.edu.
ABBREVIATIONS:

PML,

promyelocytic leukemia gene product;

CBP,

CREB binding protein;

FITC,

fluorescein isothiocyanate;

aa,

amino acid(s);

pol I and II,

polymerase I and II;

GFP,

green fluorescent protein