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Plasma transglutaminase in hypertrophic chondrocytes: expression and cell-specific intracellular activation produce cell death and externalization.

Nurminskaya M, Magee C, Nurminsky D, Linsenmayer TF - J. Cell Biol. (1998)

Bottom Line: We now have isolated a full-length cDNA for this molecule, and confirmed that it is avian factor XIIIA.This externalization most likely is effected by cell death and subsequent lysis-effected by the transglutaminase itself.Non-hypertrophic cells transfected with the same construct do not show these degenerative changes.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.

ABSTRACT
We previously used subtractive hybridization to isolate cDNAs for genes upregulated in chick hypertrophic chondrocytes (Nurminskaya, M. , and T.F. Linsenmayer. 1996. Dev. Dyn. 206:260-271). Certain of these showed homology with the "A" subunit of human plasma transglutaminase (factor XIIIA), a member of a family of enzymes that cross-link a variety of intracellular and matrix molecules. We now have isolated a full-length cDNA for this molecule, and confirmed that it is avian factor XIIIA. Northern and enzymatic analyses confirm that the molecule is upregulated in hypertrophic chondrocytes (as much as eightfold). The enzymatic analyses also show that appreciable transglutaminase activity in the hypertrophic zone becomes externalized into the extracellular matrix. This externalization most likely is effected by cell death and subsequent lysis-effected by the transglutaminase itself. When hypertrophic chondrocytes are transfected with a cDNA construct encoding the zymogen of factor XIIIA, the cells convert the translated protein to a lower molecular weight form, and they initiate cell death, become permeable to macromolecules and eventually undergo lysis. Non-hypertrophic cells transfected with the same construct do not show these degenerative changes. These results suggest that hypertrophic chondrocytes have a novel, tissue-specific cascade of mechanisms that upregulate the synthesis of plasma transglutaminase and activate its zymogen. This produces autocatalytic cell death, externalization of the enzyme, and presumably cross-linking of components within the hypertrophic matrix. These changes may in turn regulate the removal and/or calcification of this hypertrophic matrix, which are its ultimate fates.

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Upregulation of plasma transglutaminase in hypertrophic cartilage in vivo. In situ hybridization for factor XIIIA in  the tibiotarsal growth region of 14-d (A) or 20-d (B) embryos.  The arrows in A demarcate enlarged images from the pre-hypertrophic (top) and hypertrophic (bottom) zones. A′ and B′ are fluorescent images of the same field as in A and B reacted with a  mAb against collagen type X.
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Figure 2: Upregulation of plasma transglutaminase in hypertrophic cartilage in vivo. In situ hybridization for factor XIIIA in the tibiotarsal growth region of 14-d (A) or 20-d (B) embryos. The arrows in A demarcate enlarged images from the pre-hypertrophic (top) and hypertrophic (bottom) zones. A′ and B′ are fluorescent images of the same field as in A and B reacted with a mAb against collagen type X.

Mentions: The upregulation was confirmed for growth cartilages in vivo by in situ hybridization (Fig. 2). In the growth region of tibiotarsi from 14-d embryos, the signal for plasma transglutaminase shows a large increase in cells of the hypertrophic zone (Fig. 2 A, and panels demarcated by arrows). In comparison to collagen type X protein, as visualized by immunofluorescence (Fig. 2 A′), the increased signal for the transglutaminase seems to occur slightly earlier than the appearance of this hypertrophic-specific collagen.2 Both remain present throughout the remainder of the hypertrophic zone. In tissues from 20-d embryos (Fig. 2 B), the mRNA for plasma transglutaminase becomes restricted to a narrower zone. By comparison with the immunolocalization of the type X collagen (Fig. 2 B′) this is the zone of early hypertrophy.


Plasma transglutaminase in hypertrophic chondrocytes: expression and cell-specific intracellular activation produce cell death and externalization.

Nurminskaya M, Magee C, Nurminsky D, Linsenmayer TF - J. Cell Biol. (1998)

Upregulation of plasma transglutaminase in hypertrophic cartilage in vivo. In situ hybridization for factor XIIIA in  the tibiotarsal growth region of 14-d (A) or 20-d (B) embryos.  The arrows in A demarcate enlarged images from the pre-hypertrophic (top) and hypertrophic (bottom) zones. A′ and B′ are fluorescent images of the same field as in A and B reacted with a  mAb against collagen type X.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2132883&req=5

Figure 2: Upregulation of plasma transglutaminase in hypertrophic cartilage in vivo. In situ hybridization for factor XIIIA in the tibiotarsal growth region of 14-d (A) or 20-d (B) embryos. The arrows in A demarcate enlarged images from the pre-hypertrophic (top) and hypertrophic (bottom) zones. A′ and B′ are fluorescent images of the same field as in A and B reacted with a mAb against collagen type X.
Mentions: The upregulation was confirmed for growth cartilages in vivo by in situ hybridization (Fig. 2). In the growth region of tibiotarsi from 14-d embryos, the signal for plasma transglutaminase shows a large increase in cells of the hypertrophic zone (Fig. 2 A, and panels demarcated by arrows). In comparison to collagen type X protein, as visualized by immunofluorescence (Fig. 2 A′), the increased signal for the transglutaminase seems to occur slightly earlier than the appearance of this hypertrophic-specific collagen.2 Both remain present throughout the remainder of the hypertrophic zone. In tissues from 20-d embryos (Fig. 2 B), the mRNA for plasma transglutaminase becomes restricted to a narrower zone. By comparison with the immunolocalization of the type X collagen (Fig. 2 B′) this is the zone of early hypertrophy.

Bottom Line: We now have isolated a full-length cDNA for this molecule, and confirmed that it is avian factor XIIIA.This externalization most likely is effected by cell death and subsequent lysis-effected by the transglutaminase itself.Non-hypertrophic cells transfected with the same construct do not show these degenerative changes.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.

ABSTRACT
We previously used subtractive hybridization to isolate cDNAs for genes upregulated in chick hypertrophic chondrocytes (Nurminskaya, M. , and T.F. Linsenmayer. 1996. Dev. Dyn. 206:260-271). Certain of these showed homology with the "A" subunit of human plasma transglutaminase (factor XIIIA), a member of a family of enzymes that cross-link a variety of intracellular and matrix molecules. We now have isolated a full-length cDNA for this molecule, and confirmed that it is avian factor XIIIA. Northern and enzymatic analyses confirm that the molecule is upregulated in hypertrophic chondrocytes (as much as eightfold). The enzymatic analyses also show that appreciable transglutaminase activity in the hypertrophic zone becomes externalized into the extracellular matrix. This externalization most likely is effected by cell death and subsequent lysis-effected by the transglutaminase itself. When hypertrophic chondrocytes are transfected with a cDNA construct encoding the zymogen of factor XIIIA, the cells convert the translated protein to a lower molecular weight form, and they initiate cell death, become permeable to macromolecules and eventually undergo lysis. Non-hypertrophic cells transfected with the same construct do not show these degenerative changes. These results suggest that hypertrophic chondrocytes have a novel, tissue-specific cascade of mechanisms that upregulate the synthesis of plasma transglutaminase and activate its zymogen. This produces autocatalytic cell death, externalization of the enzyme, and presumably cross-linking of components within the hypertrophic matrix. These changes may in turn regulate the removal and/or calcification of this hypertrophic matrix, which are its ultimate fates.

Show MeSH
Related in: MedlinePlus