Organization of transcriptional regulatory machinery in osteoclast nuclei: compartmentalization of Runx1
Graduate School of Biomedical Sciences; Department of Cell Biology
Medical Subject Headings
Animals; Carrier Proteins; Cell Differentiation; Cell Lineage; Cell Nucleus; Cells, Cultured; Core Binding Factor Alpha 2 Subunit; DNA-Binding Proteins; Down-Regulation; Male; Membrane Glycoproteins; Mice; Mice, Inbred BALB C; NF-kappa B; Nuclear Matrix; Organ Specificity; Osteoclasts; Proto-Oncogene Proteins; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Transcription Factors; *Transcription, Genetic
Life Sciences | Medicine and Health Sciences
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-kappaB), 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.
Rights and Permissions
Citation: J Cell Physiol. 2005 Sep;204(3):871-80. Link to article on publisher's site