Dataset Information

Peptidylarginine deiminase 2 (PADI2) is a key regulator for osteoblast differentiation and bone formation through the maintenance of citrullination-mediated RUNX2 stability

ABSTRACT: Peptidylarginine deiminase (PADI) 2 catalyzes the posttranslational conversion of peptidyl-arginine to peptidyl-citrulline, a process called citrullination. However, the exact function of PADI2 in bone development and bone homeostasis remains unknown. In this study, we found that Padi2 deficiency lead to loss of bone mass and cleidocranial dysplasia (CCD)-like phenotype with delayed calvarial ossification and clavicular hypoplasia due to impaired osteoblast differentiation. Mechanistically, Padi2 depletion drastically reduced RUNX2 protein level and PADI2 stabilized RUNX2 from ubiquitin-proteasomal degradation. Furthermore, we identified a new modification at RUNX2, citrullination of arginine and its conversion to citrulline by PADI2. PADI2 citrullinates RUNX2 via a direct physical interaction and the citrullination sites at RUNX2 by PADI2 were identified by high-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Interestingly, in mouse RUNX2 isoform 1 (528 a.a), loss of R381, a citrullination site by PADI2, drastically reduced RUNX2 protein levels, indicating that the citrullination of RUNX2 by PADI2 is required for the maintenance of RUNX2 protein stability. Collectively, our study demonstrates that PADI2-mediated citrullination play key roles in bone formation and bone homeostasis. Also, CCD may result from functional defects of RUNX2 by Padi2 deficiency. These insights into the role of PADI2 in postnatal bone formation and homeostasis and CCD pathogenesis may assist in the development of new therapies for bone diseases including CCD.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Byung-gyu kim

LAB HEAD: Hyun-Mo Ryoo

PROVIDER: PXD040179 | Pride | 2023-10-24

REPOSITORIES: Pride

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Publications

Peptidylarginine deiminase 2 plays a key role in osteogenesis by enhancing RUNX2 stability through citrullination.

Kim Hyun-Jung HJ Shin Hye-Rim HR Yoon Heein H Park Min-Sang MS Kim Byung-Gyu BG Moon Jae-I JI Kim Woo-Jin WJ Park Seung Gwa SG Kim Ki-Tae KT Kim Ha-Neui HN Choi Je-Yong JY Ryoo Hyun-Mo HM

Cell death & disease 20230830 8

Peptidylarginine deiminase (PADI) 2 catalyzes the post-translational conversion of peptidyl-arginine to peptidyl-citrulline in a process called citrullination. However, the precise functions of PADI2 in bone formation and homeostasis remain unknown. In this study, our objective was to elucidate the function and regulatory mechanisms of PADI2 in bone formation employing global and osteoblast-specific Padi2 knockout mice. Our findings demonstrate that Padi2 deficiency leads to the loss of bone mas ...[more]

PMID: 37648716

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Dataset Information

Peptidylarginine deiminase 2 (PADI2) is a key regulator for osteoblast differentiation and bone formation through the maintenance of citrullination-mediated RUNX2 stability

Publications

Peptidylarginine deiminase 2 plays a key role in osteogenesis by enhancing RUNX2 stability through citrullination.

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