Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA396234 | ENA |
REPOSITORIES: ENA
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Project description:Here we report the characterization of a novel role for the retinoblastoma protein (pRb) as a regulator of osteoblast adhesion. Abrogation of pRb in osteoblasts resulted in aberrant cadherin expression and loss of adherens junctions. This produced defects suggestive of a transformed phenotype such as impaired cell-to-cell adhesion, loss of contact-dependent growth arrest, and the capacity to evade anoikis. This also resulted in profound abnormalities in bone structure. Consistent with this, microarray analyses showed that pRb regulates a wide repertoire of osteoblast cell adhesion genes. In addition, pRb loss also resulted in altered expression and function of several known regulators of cellular adhesion and adherens junction assembly, such as the Rho GTPase Rac1 and the merlin tumor suppressor. Taken together, our results show that pRb controls cell adhesion by regulating the expression and adherens junction components and by regulating the function of molecules involved in adherens junction assembly and stability. Microarray results helped us to portrait the overall influence on cell adhesion via both individual genes and pathway analysis. Experiment Overall Design: MC3T3 cells were obtained from immortalizing primary cultured mouse osteoblast cells by using 3T3 protocol. There are 3 biological replicates for each group, 6 samples in total were analyzed.
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Project description:Rho GTPases integrate control of cell structure and adhesion with downstream signaling events. In keratinocytes, RhoA is activated at early times of differentiation and plays an essential function in establishment of cellcell adhesion. We report here that, surprisingly, Rho signaling suppresses downstream gene expression events associated with differentiation. Similar inhibitory effects are exerted by a specific Rho effector, CRIK (Citron kinase), which is selectively down-modulated with differentiation, thereby allowing the normal process to occur. The suppressing function of Rho/CRIK on differentiation is associated with induction of KyoT1/2, a LIM domain protein gene implicated in integrin-mediated processes and/or Notch signaling. Like activated Rho and CRIK, elevated KyoT1/2 expression suppresses differentiation. Thus, Rho signaling exerts an unexpectedly complex role in keratinocyte differentiation, which is coupled with induction of KyoT1/2, a LIM domain protein gene with a potentially important role in control of cell self renewal. Experiment Overall Design: Total RNA from primary mouse keratinocytes infected with adeno-GFP, adeno-RhoV14, or adeno-CRIK-SK for 48 h was used for biotin-labeled cRNA probe preparation and hybridization to Affymetrix U74A gene chips. cRNA probes from each condition were tested in duplicate.
2007-09-07 | E-GEOD-3162 | biostudies-arrayexpress
Project description:Rho GTPases integrate control of cell structure and adhesion with downstream signaling events. In keratinocytes, RhoA is activated at early times of differentiation and plays an essential function in establishment of cell-cell adhesion. We report here that, surprisingly, Rho signaling suppresses downstream gene expression events associated with differentiation. Similar inhibitory effects are exerted by a specific Rho effector, CRIK (Citron kinase), which is selectively down-modulated with differentiation, thereby allowing the normal process to occur. The suppressing function of Rho/CRIK on differentiation is associated with induction of KyoT1/2, a LIM domain protein gene implicated in integrin-mediated processes and/or Notch signaling. Like activated Rho and CRIK, elevated KyoT1/2 expression suppresses differentiation. Thus, Rho signaling exerts an unexpectedly complex role in keratinocyte differentiation, which is coupled with induction of KyoT1/2, a LIM domain protein gene with a potentially important role in control of cell self renewal. Keywords: epithelial cell differentiation | gene expression | Rho signaling | stem cell
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