Organization of transcriptional regulatory machinery in osteoclast nuclei: Compartmentalization of Runx1

✍ Scribed by Laura H. Saltman; Amjad Javed; John Ribadeneyra; Sadiq Hussain; Daniel W. Young; Philip Osdoby; Alla Amcheslavsky; Andre J. van Wijnen; Janet L. Stein; Gary S. Stein; Jane B. Lian; Zvi Bar-Shavit

• Book ID: 102881731
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 642 KB
• Volume: 204
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.20329

✦ Synopsis

Abstract

The osteoclast is a highly polarized multinucleated cell that resorbs bone. Using high resolution immunofluorescence microscopy, we demonstrated that all nuclei of an osteoclast are transcriptionally active. Each nucleus within the osteoclast contains punctately organized microenvironments where regulatory complexes that support transcriptional and post‐transcriptional control reside. Functional equivalency of osteoclast nuclei is reflected by similar representation of regulatory proteins that support ribosomal RNA synthesis (nucleolin), mRNA transcription (RNA polymerase II, bromouridine triphosphate), processing of gene transcripts (SC35), signal transduction (NF‐κB), and phenotypic gene expression (Runx1). Our results establish that gene regulatory machinery is architecturally associated and compartmentalized within intranuclear microenvironments of the multiple nuclei of osteoclasts to support physiologically responsive modifications in cellular structural and functional properties. © 2005 Wiley‐Liss, Inc.