P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway

Xiaohua Wu, Shi Chen, Selina A. Orlando, Jin Yuan, Edward T. Kim, Veerendra Munugalavadla, Raghuveer S. Mali, Reuben Kapur, Feng Chun Yang

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Class IA phosphoinositide 3-kinase (PI3K) is involved in regulating many cellular functions including cell growth, proliferation, cell survival, and differentiation. The p85 regulatory subunit is a critical component of the PI3K signaling pathway. Mesenchymal stem cells (MSC) are multipotent cells that can be differentiated into osteoblasts (OBs), adipocytes, and chondrocytes under defined culture conditions. To determine whether p85α subunit of PI3K affects biological functions of MSCs, bone marrow-derived wild type (WT) and p85α-deficient (p85α-/-) cells were employed in this study. Increased cell growth, higher proliferation rate and reduced number of senescent cells were observed in MSCs lacking p85α compare with WT MSCs as evaluated by CFU-F assay, thymidine incorporation assay, and β-galactosidase staining, respectively. These functional changes are associated with the increased cell cycle, increased expression of cyclin D, cyclin E, and reduced expression of p16 and p19 in p85α-/- MSCs. In addition, a time-dependent reduction in alkaline phosphatase (ALP) activity and osteocalcin mRNA expression was observed in p85α -/- MSCs compared with WT MSCs, suggesting impaired osteoblast differentiation due to p85α deficiency in MSCs. The impaired p85α-/- osteoblast differentiation was associated with increased activation of Akt and MAPK. Importantly, bone morphogenic protein 2 (BMP2) was able to intensify the differentiation of osteoblasts derived from WT MSCs, whereas this process was significantly impaired as a result of p85α deficiency. Addition of LY294002, a PI3K inhibitor, did not alter the differentiation of osteoblasts in either genotype. However, application of PD98059, a Mek/MAPK inhibitor, significantly enhanced osteoblast differentiation in WT and p85α-/- MSCs. These results suggest that p85α plays an essential role in osteoblast differentiation from MSCs by repressing the activation of MAPK pathway.

Original languageEnglish
Pages (from-to)13512-13521
Number of pages10
JournalJournal of Biological Chemistry
Volume286
Issue number15
DOIs
StatePublished - Apr 15 2011

Fingerprint

Osteoblasts
1-Phosphatidylinositol 4-Kinase
Phosphatidylinositols
Phosphotransferases
Cell growth
Assays
Bone
Chemical activation
Galactosidases
Cyclin D
Cyclin E
2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
Osteocalcin
Cell proliferation
Chondrocytes
Growth
Stem cells
Mesenchymal Stromal Cells
Adipocytes
Thymidine

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology
  • Medicine(all)

Cite this

Wu, X., Chen, S., Orlando, S. A., Yuan, J., Kim, E. T., Munugalavadla, V., ... Yang, F. C. (2011). P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway. Journal of Biological Chemistry, 286(15), 13512-13521. https://doi.org/10.1074/jbc.M110.187351

P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway. / Wu, Xiaohua; Chen, Shi; Orlando, Selina A.; Yuan, Jin; Kim, Edward T.; Munugalavadla, Veerendra; Mali, Raghuveer S.; Kapur, Reuben; Yang, Feng Chun.

In: Journal of Biological Chemistry, Vol. 286, No. 15, 15.04.2011, p. 13512-13521.

Research output: Contribution to journalArticle

Wu, X, Chen, S, Orlando, SA, Yuan, J, Kim, ET, Munugalavadla, V, Mali, RS, Kapur, R & Yang, FC 2011, 'P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway', Journal of Biological Chemistry, vol. 286, no. 15, pp. 13512-13521. https://doi.org/10.1074/jbc.M110.187351
Wu X, Chen S, Orlando SA, Yuan J, Kim ET, Munugalavadla V et al. P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway. Journal of Biological Chemistry. 2011 Apr 15;286(15):13512-13521. https://doi.org/10.1074/jbc.M110.187351
Wu, Xiaohua ; Chen, Shi ; Orlando, Selina A. ; Yuan, Jin ; Kim, Edward T. ; Munugalavadla, Veerendra ; Mali, Raghuveer S. ; Kapur, Reuben ; Yang, Feng Chun. / P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway. In: Journal of Biological Chemistry. 2011 ; Vol. 286, No. 15. pp. 13512-13521.
@article{8733f2ea52034f2a9cbfcc0c31d70dec,
title = "P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway",
abstract = "Class IA phosphoinositide 3-kinase (PI3K) is involved in regulating many cellular functions including cell growth, proliferation, cell survival, and differentiation. The p85 regulatory subunit is a critical component of the PI3K signaling pathway. Mesenchymal stem cells (MSC) are multipotent cells that can be differentiated into osteoblasts (OBs), adipocytes, and chondrocytes under defined culture conditions. To determine whether p85α subunit of PI3K affects biological functions of MSCs, bone marrow-derived wild type (WT) and p85α-deficient (p85α-/-) cells were employed in this study. Increased cell growth, higher proliferation rate and reduced number of senescent cells were observed in MSCs lacking p85α compare with WT MSCs as evaluated by CFU-F assay, thymidine incorporation assay, and β-galactosidase staining, respectively. These functional changes are associated with the increased cell cycle, increased expression of cyclin D, cyclin E, and reduced expression of p16 and p19 in p85α-/- MSCs. In addition, a time-dependent reduction in alkaline phosphatase (ALP) activity and osteocalcin mRNA expression was observed in p85α -/- MSCs compared with WT MSCs, suggesting impaired osteoblast differentiation due to p85α deficiency in MSCs. The impaired p85α-/- osteoblast differentiation was associated with increased activation of Akt and MAPK. Importantly, bone morphogenic protein 2 (BMP2) was able to intensify the differentiation of osteoblasts derived from WT MSCs, whereas this process was significantly impaired as a result of p85α deficiency. Addition of LY294002, a PI3K inhibitor, did not alter the differentiation of osteoblasts in either genotype. However, application of PD98059, a Mek/MAPK inhibitor, significantly enhanced osteoblast differentiation in WT and p85α-/- MSCs. These results suggest that p85α plays an essential role in osteoblast differentiation from MSCs by repressing the activation of MAPK pathway.",
author = "Xiaohua Wu and Shi Chen and Orlando, {Selina A.} and Jin Yuan and Kim, {Edward T.} and Veerendra Munugalavadla and Mali, {Raghuveer S.} and Reuben Kapur and Yang, {Feng Chun}",
year = "2011",
month = "4",
day = "15",
doi = "10.1074/jbc.M110.187351",
language = "English",
volume = "286",
pages = "13512--13521",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "15",

}

TY - JOUR

T1 - P85α regulates osteoblast differentiation by cross-talking with the MAPK pathway

AU - Wu, Xiaohua

AU - Chen, Shi

AU - Orlando, Selina A.

AU - Yuan, Jin

AU - Kim, Edward T.

AU - Munugalavadla, Veerendra

AU - Mali, Raghuveer S.

AU - Kapur, Reuben

AU - Yang, Feng Chun

PY - 2011/4/15

Y1 - 2011/4/15

N2 - Class IA phosphoinositide 3-kinase (PI3K) is involved in regulating many cellular functions including cell growth, proliferation, cell survival, and differentiation. The p85 regulatory subunit is a critical component of the PI3K signaling pathway. Mesenchymal stem cells (MSC) are multipotent cells that can be differentiated into osteoblasts (OBs), adipocytes, and chondrocytes under defined culture conditions. To determine whether p85α subunit of PI3K affects biological functions of MSCs, bone marrow-derived wild type (WT) and p85α-deficient (p85α-/-) cells were employed in this study. Increased cell growth, higher proliferation rate and reduced number of senescent cells were observed in MSCs lacking p85α compare with WT MSCs as evaluated by CFU-F assay, thymidine incorporation assay, and β-galactosidase staining, respectively. These functional changes are associated with the increased cell cycle, increased expression of cyclin D, cyclin E, and reduced expression of p16 and p19 in p85α-/- MSCs. In addition, a time-dependent reduction in alkaline phosphatase (ALP) activity and osteocalcin mRNA expression was observed in p85α -/- MSCs compared with WT MSCs, suggesting impaired osteoblast differentiation due to p85α deficiency in MSCs. The impaired p85α-/- osteoblast differentiation was associated with increased activation of Akt and MAPK. Importantly, bone morphogenic protein 2 (BMP2) was able to intensify the differentiation of osteoblasts derived from WT MSCs, whereas this process was significantly impaired as a result of p85α deficiency. Addition of LY294002, a PI3K inhibitor, did not alter the differentiation of osteoblasts in either genotype. However, application of PD98059, a Mek/MAPK inhibitor, significantly enhanced osteoblast differentiation in WT and p85α-/- MSCs. These results suggest that p85α plays an essential role in osteoblast differentiation from MSCs by repressing the activation of MAPK pathway.

AB - Class IA phosphoinositide 3-kinase (PI3K) is involved in regulating many cellular functions including cell growth, proliferation, cell survival, and differentiation. The p85 regulatory subunit is a critical component of the PI3K signaling pathway. Mesenchymal stem cells (MSC) are multipotent cells that can be differentiated into osteoblasts (OBs), adipocytes, and chondrocytes under defined culture conditions. To determine whether p85α subunit of PI3K affects biological functions of MSCs, bone marrow-derived wild type (WT) and p85α-deficient (p85α-/-) cells were employed in this study. Increased cell growth, higher proliferation rate and reduced number of senescent cells were observed in MSCs lacking p85α compare with WT MSCs as evaluated by CFU-F assay, thymidine incorporation assay, and β-galactosidase staining, respectively. These functional changes are associated with the increased cell cycle, increased expression of cyclin D, cyclin E, and reduced expression of p16 and p19 in p85α-/- MSCs. In addition, a time-dependent reduction in alkaline phosphatase (ALP) activity and osteocalcin mRNA expression was observed in p85α -/- MSCs compared with WT MSCs, suggesting impaired osteoblast differentiation due to p85α deficiency in MSCs. The impaired p85α-/- osteoblast differentiation was associated with increased activation of Akt and MAPK. Importantly, bone morphogenic protein 2 (BMP2) was able to intensify the differentiation of osteoblasts derived from WT MSCs, whereas this process was significantly impaired as a result of p85α deficiency. Addition of LY294002, a PI3K inhibitor, did not alter the differentiation of osteoblasts in either genotype. However, application of PD98059, a Mek/MAPK inhibitor, significantly enhanced osteoblast differentiation in WT and p85α-/- MSCs. These results suggest that p85α plays an essential role in osteoblast differentiation from MSCs by repressing the activation of MAPK pathway.

UR - http://www.scopus.com/inward/record.url?scp=79953900838&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79953900838&partnerID=8YFLogxK

U2 - 10.1074/jbc.M110.187351

DO - 10.1074/jbc.M110.187351

M3 - Article

VL - 286

SP - 13512

EP - 13521

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 15

ER -