Project description:Very little is known about how intervertebral disc (IVD) is formed or maintained. Members of the TGF-ß superfamily are secreted signaling proteins that regulate many aspects of development including cellular differentiation. We recently showed that deletion of Tgfbr2 in Col2a expressing tissue results in alterations in development of IVD annulus fibrosus. The results suggested TGF-ß has an important role in regulating development of the axial skeleton, however, the mechanistic basis of TGF-ß action in these specialized joints is not known. One of the hurdles to understanding development of IVD is a lack of known markers. To identify genes that are enriched in the developing IVD and to begin to understand the mechanism of TGF-ß action in IVD development, we undertook a global analysis of gene expression comparing gene expression profiles in developing vertebrae and IVD. We also compared expression profiles in tissues from wild type and Tgfbr2 mutant mice. Lists of IVD and vertebrae enriched genes were generated. Expression patterns for several genes were verified either through in situ hybridization or literature/ database searches resulting in a list of genes that can be used as markers of IVD. Cluster analysis using genes listed under the Gene Ontology terms multicellular organism development and pattern specification indicated that mutant IVD more closely resembled vertebrae than wild type IVD. We propose TGF-ß has two functions in IVD development: 1) to prevent chondrocyte differentiation in the presumptive IVD and 2) to promote differentiation of annulus fibrosus from sclerotome. We have identified genes that are enriched in the IVD and regulated by TGF-ß that warrant further investigation as regulators of IVD development. Thirteen samples were analyzed. This includes three biological replicates of laser captured IVD from E13.5 day control mice, three biological replicates of laser captured vertebrae from the same E13.5 day control mice, three biological relicates of laser captured vertebrae from E13.5 day Col2aCre;Tgfbr2lox/lox mice, and four biological replicates of laser captured IVD from E13.5 day Col2aCre;Tgfbr2lox/lox mice.
Project description:Very little is known about how intervertebral disc (IVD) is formed or maintained. Members of the TGF-ß superfamily are secreted signaling proteins that regulate many aspects of development including cellular differentiation. We recently showed that deletion of Tgfbr2 in Col2a expressing tissue results in alterations in development of IVD annulus fibrosus. The results suggested TGF-ß has an important role in regulating development of the axial skeleton, however, the mechanistic basis of TGF-ß action in these specialized joints is not known. One of the hurdles to understanding development of IVD is a lack of known markers. To identify genes that are enriched in the developing IVD and to begin to understand the mechanism of TGF-ß action in IVD development, we undertook a global analysis of gene expression comparing gene expression profiles in developing vertebrae and IVD. We also compared expression profiles in tissues from wild type and Tgfbr2 mutant mice. Lists of IVD and vertebrae enriched genes were generated. Expression patterns for several genes were verified either through in situ hybridization or literature/ database searches resulting in a list of genes that can be used as markers of IVD. Cluster analysis using genes listed under the Gene Ontology terms multicellular organism development and pattern specification indicated that mutant IVD more closely resembled vertebrae than wild type IVD. We propose TGF-ß has two functions in IVD development: 1) to prevent chondrocyte differentiation in the presumptive IVD and 2) to promote differentiation of annulus fibrosus from sclerotome. We have identified genes that are enriched in the IVD and regulated by TGF-ß that warrant further investigation as regulators of IVD development.
Project description:Very little is known about how intervertebral disc (IVD) is formed or maintained. Members of the TGF-beta superfamily are secreted signaling proteins that regulate many aspects of development including cellular differentiation. We recently showed that deletion of Tgfbr2 in Col2a expressing tissue results in alterations in development of IVD annulus fibrosus. The results suggested TGF-beta has an important role in regulating development of the axial skeleton, however, the mechanistic basis of TGF-beta action in these specialized joints is not known. To understand the mechanism of TGF-beta action in IVD development, we undertook a global analysis of gene expression comparing gene expression profiles in sclerotome cultures treated with TGF-beta or BMP4. As expected, treatment with BMP4 resulted in up-regulation of cartilage marker genes including Acan, Sox 5, Sox6, and Sox9. In contrast, treatment with TGF-beta1 did not regulate expression of cartilage markers but instead resulted in up-regulation of many IVD markers including Fmod and Adamtsl2. We propose TGF-beta has two functions in IVD development: 1) to prevent chondrocyte differentiation in the presumptive IVD and 2) to promote differentiation of annulus fibrosus from sclerotome. We have identified genes that are enriched in the IVD and regulated by TGF-beta that warrant further investigation as regulators of IVD development. Nine samples were analyzed. Three biological replicates of untreated sclerotome grown in micromass culture. Three biological replicates of cells treated with 50 ng/ml BMP4 for 8 hours and three biological replicates of cells treated with 5 ng/ ml TGF-beta1 for 8 hours.
Project description:Very little is known about how intervertebral disc (IVD) is formed or maintained. Members of the TGF-ß superfamily are secreted signaling proteins that regulate many aspects of development including cellular differentiation. We recently showed that deletion of Tgfbr2 in Col2a expressing tissue results in alterations in development of IVD annulus fibrosus. The results suggested TGF-ß has an important role in regulating development of the axial skeleton, however, the mechanistic basis of TGF-ß action in these specialized joints is not known. To understand the mechanism of TGF-ß action in IVD development, we undertook a global analysis of gene expression comparing gene expression profiles in sclerotome cultures treated with TGF-ß or BMP4. As expected, treatment with BMP4 resulted in up-regulation of cartilage marker genes including Acan, Sox 5, Sox6, and Sox9. In contrast, treatment with TGF-ß1 did not regulate expression of cartilage markers but instead resulted in up-regulation of many IVD markers including Fmod and Adamtsl2. We propose TGF-ß has two functions in IVD development: 1) to prevent chondrocyte differentiation in the presumptive IVD and 2) to promote differentiation of annulus fibrosus from sclerotome. We have identified genes that are enriched in the IVD and regulated by TGF-ß that warrant further investigation as regulators of IVD development.
Project description:Pax1 and Pax9 play redundant, synergistic functions in the patterning and differentiation of the sclerotomal cells that give rise to the vertebral bodies and intervertebral discs (IVD) of the axial skeleton. Gene expression profiling of an enriched population of Pax1/Pax9-expressing cells of the embryonic IVD revealed that Pax1 and Pax9 regulate cell proliferation, cartilage development, collagen fibrillogenesis and other processes vital in early IVD morphogenesis. Twenty-nine of the Pax1/Pax9 targets are also associated with axial skeletal defects that phenocopy Pax1/Pax9-deficient mice. Pax1 likely auto-regulates itself and is up-regulated in the absence of Pax9, clarifying how it compensates for the loss of Pax9, while Pax9 is unaffected by the loss of Pax1. Pax1 and Pax9 positively regulate several of the cartilage development genes known to be regulated by the “Sox trio” (Sox5/Sox6/Sox9).
Project description:IDD (Intervertebral disc degeneration) is an important cause of low back pain which has become a global public health problem. We aimed to determine the role of glutamine in the development of IDD and evaluate its mechanism to prevent IDD.
Project description:Assessment of the putative differential gene expression profiles in high osmolality-treated bovine nucleus pulposus intervertebral disc cells for a short (5 h) and a long (24 h) time period. Identification of novel genes up- or down-regulated as an early or a late response to hyperosmotic stress. A 5 and 24 h-hyperosmotic treatment of nucleus pulposus cells led to transcriptional changes in >100 and 200 genes, respectively. Nucleus pulposus intervertebral disc cells were exposed to hyperosmotic stress for 5 and 24 h before RNA extraction and transcriptomics analysis. Three biological replicates were tested for each condition. Selected genes found to be differentially expressed were validated by RT-qPCR. Functional experiments were performed in order to assess the role of specific proteins encoded by genes found to be up-regulated in the osmo-reguatory response of intervertebral disc cells.
Project description:Intervertebral disc degeneration is the main cause of low back pain and the mechanism of which is far from fully revealed. Although multiple factors are related to the intervertebral disc degeneration, inflammation and matrix metabolism dysregulation are the two key factors that play an important role in degeneration. Here, we found that CHSY3 is highly related to the nucleus pulposus degeneration. We generated CHSY3 knockout mice using Crisper/Cas9 system, and the NP cells are studied in this experiment.
Project description:Back pain and intervertebral disc degeneration are prevalent, costly, and widely treated by manual therapies, yet the underlying causes of these diseases are indeterminate as are the scientific bases for such treatments. The present studies characterize the effects of repetitive in vivo manual loads on porcine intervertebral disc using RNA deep sequencing. A single session of repetitive manual loading applied to the lumbar spine induced both up- and down-regulation of a variety of genes transcribed by cells in the ventral annuli fibrosi. The effect of manual therapy at the level of loading was greater than at a level distant to the applied load. Gene ontology and molecular pathway analyses categorized biological, molecular, and cellular functions influenced by repetitive manual loading, with over-representation of membrane, transmembrane, and pericellular activities. The present studies support previous findings of intervertebral disc cell mechanotransduction, and are the first to report comprehensively on the repertoire of gene targets influenced by mechanical loads associated with manual therapy interventions. The present study defines the cellular response of repeated, low-amplitude loads on the annuli fibrosi and lays the foundation for future work defining how the intervertebral disc responds to single or low-frequency manual loads typical of those applied clinically.
Project description:Vertebrate axial skeletal patterning is controlled by coordinated collinear expression of Hox genes and axial level-dependent activity of Hox protein combinations. Transcription factors of the Meis family act as cofactors of Hox proteins and profusely bind to Hox complex DNA, however their roles in mammalian axial patterning have not been established. Similarly, retinoic acid (RA) is known to regulate axial skeletal element identity through the transcriptional activity of its receptors, however whether this role is related to Meis/Hox regulation or functions in axial patterning remains unknown. Here we study the role of Meis factors in axial skeleton formation and its relationship to the RA pathway by characterizing Meis1, Meis2 and Raldh2 mutant mice. We report that Meis and Raldh2 regulate each other in a positive feedback regulatory loop that controls axial skeletal identity. Meis elimination produces homeotic transformations similar to those found in Raldh2 and anterior-Hox mutants and disrupts the expression of Hox target genes without changing the transcriptional profiles of Hox complexes. We propose that Meis regulates vertebrate axial skeleton patterning by exclusively affecting Hox protein function, and that alterations in RA levels can produce homeotic transformations without altering Hox transcription through regulating Meis expression.