Protein cross-linking mediated by tissue transglutaminase correlates with the maturation of extracellular matrices during lung development.
Am J Respir Cell Mol Biol
; 17(3): 334-43, 1997 Sep.
Article
em En
| MEDLINE
| ID: mdl-9308920
ABSTRACT
At birth, the mammalian lung is still immature. The alveoli are not yet formed and the interairspace walls contain two capillary layers which are separated by an interstitial core. After alveolarization (first 2 postnatal weeks in rats) the alveolar septa mature their capillary layers merge, the amount of connective tissue decreases, and the mature lung parenchyma is formed (second and third week). During the first 3 wk of life the role of tissue transglutaminase (tTG) was studied in rat lung by immunostaining of cryostat and paraffin sections, by Northern and Western blotting, and by a quantitative determination of gamma-glutamyl-epsilon-lysine. While enzyme activity and intracellular tTG were already present before term, the enzyme product (gamma-glutamyl-epsilon-lysine-crosslink) and extracellular tTG appeared between postnatal days 10 and 19 in the lung parenchyma. In large blood vessels and large airways, which mature earlier than the parenchyma, both the enzyme product and extracellular tTG had already appeared at the end of the first postnatal week. We conclude that tTG is expressed and externalized into the extracellular matrix of lung shortly before maturation of an organ area. Because tTG covalently and irreversibly crosslinks extracellular matrix proteins, we hypothesize that it may prevent or delay further remodeling of basement membranes and may stabilize other extracellular components, such as microfibrils.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Transglutaminases
/
Reagentes de Ligações Cruzadas
/
Matriz Extracelular
/
Pulmão
Limite:
Animals
/
Pregnancy
Idioma:
En
Revista:
Am J Respir Cell Mol Biol
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Suíça