First Author | Ferron M | Year | 2013 |
Journal | Genes Dev | Volume | 27 |
Issue | 8 | Pages | 955-69 |
PubMed ID | 23599343 | Mgi Jnum | J:198454 |
Mgi Id | MGI:5496757 | Doi | 10.1101/gad.213827.113 |
Citation | Ferron M, et al. (2013) A RANKL-PKCbeta-TFEB signaling cascade is necessary for lysosomal biogenesis in osteoclasts. Genes Dev 27(8):955-69 |
abstractText | Bone resorption by osteoclasts requires a large number of lysosomes that release proteases in the resorption lacuna. Whether lysosomal biogenesis is a consequence of the action of transcriptional regulators of osteoclast differentiation or is under the control of a different and specific transcriptional pathway remains unknown. We show here, through cell-based assays and cell-specific gene deletion experiments in mice, that the osteoclast differentiation factor RANKL promotes lysosomal biogenesis once osteoclasts are differentiated through the selective activation of TFEB, a member of the MITF/TFE family of transcription factors. This occurs following PKCbeta phosphorylation of TFEB on three serine residues located in its last 15 amino acids. This post-translational modification stabilizes and increases the activity of this transcription factor. Supporting these biochemical observations, mice lacking in osteoclasts--either TFEB or PKCbeta--show decreased lysosomal gene expression and increased bone mass. Altogether, these results uncover a RANKL-dependent signaling pathway taking place in differentiated osteoclasts and culminating in the activation of TFEB to enhance lysosomal biogenesis-a necessary step for proper bone resorption. |