RNA-seq expression profiling of cortical bone from ephrin B2 deficient and control mice
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE110795 | GEO | 2019/07/02
REPOSITORIES: GEO
Similar Datasets
Project description:Mechanical force is a fundamental regulator of bone development and homeostasis. Mechanosensitive osteocytes are the most abundant bone cells that form interconnected dendrites to respond to mechanical stimuli and interact with the bone-forming osteoblasts and the bone-remodeling osteoclasts. However, the molecular mechanisms underlying osteocyte maturation and dendrite formation remain unclear. By generating a Piezo1 "knock-out" osteocyte cell line, we identified a key role of Piezo1-mediated mechanotransduction in osteocyte differentiation. QRT-PCR analysis revealed delayed osteocyte differentiation in the Piezo1 KO cells relative to WT cells. By performing bulk RNA sequencing of WT and Piezo1 KO OCY454 cells at early (D1), intermediate (D14), and late (D28) stages of differentiation allowed for the identification of key signaling pathways in driving normal osteocyte dfiferentiation, as well as those regulated by Piezo1 mechanotransduction.
2024-09-20 | GSE277264 | GEO
Project description:Jason M. Graham, Bruce P. Ayati, Sarah A. Holstein & James A. Martin. The role of osteocytes in targeted bone remodeling: a mathematical model. PLoS ONE 8, 5 (2013).
Until recently many studies of bone remodeling at the cellular level have focused on the behavior of mature osteoblasts and osteoclasts, and their respective precursor cells, with the role of osteocytes and bone lining cells left largely unexplored. This is particularly true with respect to the mathematical modeling of bone remodeling. However, there is increasing evidence that osteocytes play important roles in the cycle of targeted bone remodeling, in serving as a significant source of RANKL to support osteoclastogenesis, and in secreting the bone formation inhibitor sclerostin. Moreover, there is also increasing interest in sclerostin, an osteocyte-secreted bone formation inhibitor, and its role in regulating local response to changes in the bone microenvironment. Here we develop a cell population model of bone remodeling that includes the role of osteocytes, sclerostin, and allows for the possibility of RANKL expression by osteocyte cell populations. We have aimed to give a simple, yet still tractable, model that remains faithful to the underlying system based on the known literature. This model extends and complements many of the existing mathematical models for bone remodeling, but can be used to explore aspects of the process of bone remodeling that were previously beyond the scope of prior modeling work. Through numerical simulations we demonstrate that our model can be used to explore theoretically many of the qualitative features of the role of osteocytes in bone biology as presented in recent literature.
2024-09-02 | BIOMD0000000721 | BioModels
Project description:Estrogens are well known steroid hormones necessary to maintain bone health. In addition, mechanical loading, which estrogen signaling may intersect with the Wnt/β-catenin pathway, is also essential for bone health. As osteocytes are known as the major mechanosensory cells embedded in mineralized bone matrix, osteocyte ERα deletion mice (ERαÎOcy/ÎOcy) were generated by mating ERα floxed mice with Dmp1-Cre mice to determine functions of ERα in osteocytes. Trabecular bone mineral density of female, but not male ERαÎOcy/ÎOcy mice was significantly decreased. Bone formation parameters in ERαÎOcy/ÎOcy were significantly decreased while osteoclast parameters were unchanged. This suggests that ERα in osteocytes exerts osteoprotective function by positively controlling bone formation. To identify potential targets of ERα, gene array analysis of Dmp1-GFP osteocytes FACS sorted from ERαÎOcy/ÎOcy and control mice was performed. Expression of Mdk and Sostdc1, both known inhibitors of Wnt, were significantly increased without alteration of the mature osteocyte marker Sost or β-catenin. Hindlimb unloading exacerbated the trabecular bone loss, but surprisingly cortical bone was resistant. These studies show that ERα in osteocytes has osteoprotective effects in trabecular bone through regulating expression of Wnt antagonists, but conversely plays a negative role in cortical bone loss due to unloading. Wild type and osteocyte-specific Estrogen Receptor alpha knock-out mice were generated. The number of both genotypes of mice was three. Calvarial osteocytes of both genotypes harboring Dmp1-GFP were extracted by sequential enzymatic digestion, followed by FACS Aria sorting and total RNAs were purified for Affymetix GeneChip microarray analysis without pooling.
2013-12-12 | E-GEOD-41997 | biostudies-arrayexpress
Project description:Osteocytes are long-lived, highly interconnected, terminally differentiated osteoblasts which reside within mineralized bone matrix. They constitute about 95% of adult bone cells and play important functions in the regulation of bone remodeling, phosphate homeostasis, and mechanical stimuli sensing and response. However, the role of osteocytes in the pathogenesis of congenital diseases of bone such as osteogenesis imperfecta (OI) is poorly understood. This study characterized in vivo transcriptional changes in osteocytes from the CrtapKO and oim/oim mouse models of OI, using RNA-sequencing on osteocyte-enriched cortical bone from femur and tibia. These models were chosen because they mimic two types of OI with different genetic mutations which result in distinct type I collagen defects. Hundreds of transcripts were dysregulated in either model of OI compared to WT, but 281 of these were similarly up- or down-regulated in both. Conversely, very few transcripts were differentially expressed between the CrtapKO and oim/oim mice, indicating that distinct alterations in type I collagen can lead to shared pathogenic processes and similar phenotypic outcomes. Bioinformatics analyses identified several critical hubs of dysregulation that were enriched in annotation terms such as development and differentiation, ECM and collagen fibril organization, cell adhesion, signaling, regulatory processes, pattern binding, chemotaxis, and cell projections. The data further indicated alterations in important signaling pathways such as WNT and TGF-β. Overall, our study suggested that the osteocyte transcriptome is broadly dysregulated in OI, that transcriptomic alterations in OI can be strikingly similar despite arising from different genetic mutations, and that the potential consequences of osteocyte dysregulation deserve further investigation.
2020-07-21 | GSE154748 | GEO
Project description:Some cuboidal osteoblasts differentiate into bone-embedded, dendrite-bearing osteocytes through the poorly-understood process of osteocytogenesis. Here, we report that the transcription factor Sp7 plays an essential role in osteocytogenesis. Severe defects in bone integrity and osteocyte dendrite morphology are noted in mice lacking Sp7 at the stage of the osteoblast-to-osteocyte transition. In osteocytes, Sp7 controls expression of a neuronally-enriched gene network. Analysis of the osteocyte-specific Sp7 cistrome reveals distinct genomic binding motifs and target sites distinct from those in osteoblasts. Amongst osteocyte-specific Sp7 targets, the secreted peptide osteocrin rescues Sp7-deficient defects. Single-cell transcriptional profiling of cells undergoing osteocytogenesis identifies novel Sp7-dependent transitional cell types enriched in genes linked to human fracture risk. Finally, humans with an SP7 R316C mutation display osteocyte morphology defects similar to those observed in mouse models. These findings demonstrate that cuboidal osteoblasts use a neuronally-enriched Sp7/osteocrin gene expression program to differentiate into dendrite-bearing osteocytes.
2021-09-20 | GSE154718 | GEO
Project description:Some cuboidal osteoblasts differentiate into bone-embedded, dendrite-bearing osteocytes through the poorly-understood process of osteocytogenesis. Here, we report that the transcription factor Sp7 plays an essential role in osteocytogenesis. Severe defects in bone integrity and osteocyte dendrite morphology are noted in mice lacking Sp7 at the stage of the osteoblast-to-osteocyte transition. In osteocytes, Sp7 controls expression of a neuronally-enriched gene network. Analysis of the osteocyte-specific Sp7 cistrome reveals distinct genomic binding motifs and target sites distinct from those in osteoblasts. Amongst osteocyte-specific Sp7 targets, the secreted peptide osteocrin rescues Sp7-deficient defects. Single-cell transcriptional profiling of cells undergoing osteocytogenesis identifies novel Sp7-dependent transitional cell types enriched in genes linked to human fracture risk. Finally, humans with an SP7 R316C mutation display osteocyte morphology defects similar to those observed in mouse models. These findings demonstrate that cuboidal osteoblasts use a neuronally-enriched Sp7/osteocrin gene expression program to differentiate into dendrite-bearing osteocytes.
2021-09-20 | GSE154717 | GEO
Project description:Some cuboidal osteoblasts differentiate into bone-embedded, dendrite-bearing osteocytes through the poorly-understood process of osteocytogenesis. Here, we report that the transcription factor Sp7 plays an essential role in osteocytogenesis. Severe defects in bone integrity and osteocyte dendrite morphology are noted in mice lacking Sp7 at the stage of the osteoblast-to-osteocyte transition. In osteocytes, Sp7 controls expression of a neuronally-enriched gene network. Analysis of the osteocyte-specific Sp7 cistrome reveals distinct genomic binding motifs and target sites distinct from those in osteoblasts. Amongst osteocyte-specific Sp7 targets, the secreted peptide osteocrin rescues Sp7-deficient defects. Single-cell transcriptional profiling of cells undergoing osteocytogenesis identifies novel Sp7-dependent transitional cell types enriched in genes linked to human fracture risk. Finally, humans with an SP7 R316C mutation display osteocyte morphology defects similar to those observed in mouse models. These findings demonstrate that cuboidal osteoblasts use a neuronally-enriched Sp7/osteocrin gene expression program to differentiate into dendrite-bearing osteocytes.
2021-09-20 | GSE154716 | GEO
Project description:Purpose of arrays were to determine what the effect of deletion of Mbtps1 gene was on gene expression of osteocytes in bone in vivo. DMP1 cre driver was used to delete the Mbtps1 gene in osteocytes and osteoblasts in bone. We then isolated osteocyte enriched bone particles from 40 week old male mice to determine the effect of this deletion on gene expression. We have previously shown that Mbtps1 is needed for transcription of Phex, DMP1, and MEPE genes in osteoblasts in culture. Arrays showed these genes were reduced as expected in osteocytes in vivo. Controls represent osteocyte enriched bone from 40 week old littermates. Also, as expected, Mbtps1 expression was reduced in these knockout mice
2015-12-29 | GSE69975 | GEO
Project description:RNA-seq analysis of transcriptome of osteocytes isolated from femora cortical bone of 5 mo old C57BL6 mice with WT or PPARa KO genotype. Conclusion: In osteocytes, PPARα controls large number of transcripts coding for signaling proteins and osteocyte secretome which regulates development of bone marrow adipose tissue and peripheral fat metabolism.
2023-03-28 | GSE225595 | GEO
Project description:Estrogens are well known steroid hormones necessary to maintain bone health. In addition, mechanical loading, which estrogen signaling may intersect with the Wnt/β-catenin pathway, is also essential for bone health. As osteocytes are known as the major mechanosensory cells embedded in mineralized bone matrix, osteocyte ERα deletion mice (ERαΔOcy/ΔOcy) were generated by mating ERα floxed mice with Dmp1-Cre mice to determine functions of ERα in osteocytes. Trabecular bone mineral density of female, but not male ERαΔOcy/ΔOcy mice was significantly decreased. Bone formation parameters in ERαΔOcy/ΔOcy were significantly decreased while osteoclast parameters were unchanged. This suggests that ERα in osteocytes exerts osteoprotective function by positively controlling bone formation. To identify potential targets of ERα, gene array analysis of Dmp1-GFP osteocytes FACS sorted from ERαΔOcy/ΔOcy and control mice was performed. Expression of Mdk and Sostdc1, both known inhibitors of Wnt, were significantly increased without alteration of the mature osteocyte marker Sost or β-catenin. Hindlimb unloading exacerbated the trabecular bone loss, but surprisingly cortical bone was resistant. These studies show that ERα in osteocytes has osteoprotective effects in trabecular bone through regulating expression of Wnt antagonists, but conversely plays a negative role in cortical bone loss due to unloading.
2013-12-12 | GSE41997 | GEO