Enzymatic activity and in vivo distribution of 5'-nucleotidase, an extracellular matrix binding glycoprotein, during the development of chicken striated muscle.
The ecto-enzyme 5'-nucleotidase isolated from chicken gizzard has previously been shown to be a potent ligand of two glycoproteins of the extracellular matrix, namely fibronectin and laminin. Using immunofluorescent labeling techniques we observed that 5'-nucleotidase codistributed with laminin during the development of chicken striated muscle. In contrast, ecto-5'-nucleotidase was only faintly detectable on cells surrounded by a matrix expressing high levels of fibronectin. This distribution pattern distinguished 5'-nucleotidase from the pluripotent extracellular matrix receptors, chicken beta 1-integrins, which are expressed equally well in muscle and connective tissue. In addition, the specific activity of striated muscle ecto-5'-nucleotidase was stable during development and increased markedly posthatching. At each age considered, this specific activity corresponded to an 80-kDa enzyme which was inhibited by alpha,beta-methyleneadenosine diphosphate or by a monoclonal antibody directed against the smooth muscle isoform of the enzyme. Previous in vitro studies have revealed that 5'-nucleotidase is involved in the spreading of various mesenchyme-derived cells, such as chicken embryonic fibroblasts and myoblasts, on a laminin substrate. A prerequisite to examining a potential in vivo role for 5'-nucleotidase as an extracellular matrix ligand was to study its distribution. In adult muscle, 5'-nucleotidase displayed a more restricted distribution than in embryo. Results show that, in vivo, 5'-nucleotidase is revealed by immunofluorescent labeling using poly- and monoclonal antibodies to chicken gizzard 5'-nucleotidase in two structures, the costameres and myotendinous junctions, which are closely related to the focal adhesion sites observed in cell culture.
Mehul
B
B
UNITE 180 INSERM, Laboratoire de Glycobiologie et Reconnaissance Cellulaires, Paris, France.
Doyennette-Moyne
M A
MA
Aubery
M
M
Codogno
P
P
Mannherz
H G
HG
D015720:5'-Nucleotidase / Q000032:analysis / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal; D001485:Basement Membrane / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens; D004591:Electrophoresis, Polyacrylamide Gel; D005109:Extracellular Matrix / Q000378:metabolism; D005353:Fibronectins / Q000032:analysis; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000032:analysis / Q000378:metabolism*; D016023:Integrins / Q000032:analysis; D007797:Laminin / Q000032:analysis; D008854:Microscopy, Electron; D008970:Molecular Weight; D009132:Muscles / Q000166:cytology / Q000196:embryology* / Q000201:enzymology*; D009218:Myosins / Q000032:analysis; D009708:Nucleotidases / Q000032:analysis / Q000378:metabolism; D012508:Sarcolemma / Q000201:enzymology / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D005353:Fibronectins; D006023:Glycoproteins; D016023:Integrins; D007797:Laminin; D009708:Nucleotidases; C018775:adenosine monophosphatase; D015720:5'-Nucleotidase; D009218:Myosins