Dataset Information

Loss of ?-Actin Leads to Accelerated Mineralization and Dysregulation of Osteoblast-Differentiation Genes during Osteogenic Reprogramming.

ABSTRACT: Actin plays fundamental roles in both the cytoplasm and the cell nucleus. In the nucleus, ?-actin regulates neuronal reprogramming by consolidating a heterochromatin landscape required for transcription of neuronal gene programs, yet it remains unknown whether it has a role in other differentiation models. To explore the potential roles of ?-actin in osteogenesis, ?-actin wild-type (WT) and ?-actin knockout (KO) mouse embryonic fibroblasts (MEFs) are reprogrammed to osteoblast-like cells using small molecules in vitro. It is discovered that loss of ?-actin leads to an accelerated mineralization phenotype (hypermineralization), accompanied with enhanced formation of extracellular hydroxyapatite microcrystals, which originate in the mitochondria in the form of microgranules. This phenotype is a consequence of rapid upregulation of mitochondrial genes including those involved in oxidative phosphorylation (OXPHOS) in reprogrammed KO cells. It is further found that osteogenic gene programs are differentially regulated between WT and KO cells, with clusters of genes exhibiting different temporal expression patterns. A novel function for ?-actin in osteogenic reprogramming through a mitochondria-based mechanism that controls cell-mediated mineralization is proposed.

SUBMITTER: Gjorgjieva T

PROVIDER: S-EPMC7709978 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Loss of β-Actin Leads to Accelerated Mineralization and Dysregulation of Osteoblast-Differentiation Genes during Osteogenic Reprogramming.

Gjorgjieva Tamara T Xie Xin X Commins Patrick P Pasricha Renu R Mahmood Syed Raza SR Gunsalus Kristin C KC Naumov Panče P Percipalle Piergiorgio P

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20201027 23

Actin plays fundamental roles in both the cytoplasm and the cell nucleus. In the nucleus, β-actin regulates neuronal reprogramming by consolidating a heterochromatin landscape required for transcription of neuronal gene programs, yet it remains unknown whether it has a role in other differentiation models. To explore the potential roles of β-actin in osteogenesis, β-actin wild-type (WT) and β-actin knockout (KO) mouse embryonic fibroblasts (MEFs) are reprogrammed to o ...[more]

PMID: 33304760

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Dataset Information

Loss of ?-Actin Leads to Accelerated Mineralization and Dysregulation of Osteoblast-Differentiation Genes during Osteogenic Reprogramming.

Publications

Loss of <i>β</i>-Actin Leads to Accelerated Mineralization and Dysregulation of Osteoblast-Differentiation Genes during Osteogenic Reprogramming.

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