期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2010
卷号：107
期号：7
页码：3117-3122
DOI：10.1073/pnas.0912779107
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Regulation of irreversible cell lineage commitment depends on a delicate balance between positive and negative regulators, which comprise a sophisticated network of transcription factors. Receptor activator of NF-{kappa}B ligand (RANKL) stimulates the differentiation of bone-resorbing osteoclasts through the induction of nuclear factor of activated T cells c1 (NFATc1), the essential transcription factor for osteoclastogenesis. Osteoclast-specific robust induction of NFATc1 is achieved through an autoamplification mechanism, in which NFATc1 is constantly activated by calcium signaling while the negative regulators of NFATc1 are suppressed. However, it has been unclear how such negative regulators are repressed during osteoclastogenesis. Here we show that B lymphocyte-induced maturation protein-1 (Blimp1; encoded by Prdm1), which is induced by RANKL through NFATc1 during osteoclastogenesis, functions as a transcriptional repressor of anti-osteoclastogenic genes such as Irf8 and Mafb. Overexpression of Blimp1 leads to an increase in osteoclast formation, and Prdm1-deficient osteoclast precursor cells do not undergo osteoclast differentiation efficiently. The importance of Blimp1 in bone homeostasis is underscored by the observation that mice with an osteoclast-specific deficiency in the Prdm1 gene exhibit a high bone mass phenotype caused by a decreased number of osteoclasts. Thus, NFATc1 choreographs the determination of cell fate in the osteoclast lineage by inducing the repression of negative regulators as well as through its effect on positive regulators.
关键词：B lymphocyte induced maturation protein 1 ; nuclear factor of activated T cells c1 ; osteoclastogenesis ; transcription ; bone
