Externalization of an endogenous chicken muscle lectin with in vivo development.

Abstract

Chicken-lactose-lectin-l (CLL-l), an endogenous lectin that is developmentally regulated in embryonic muscle, was localized by immunohistochemical techniques is tissue samples taken at various stages of in vivo development and in primary muscle cultures. Lectin, which was diffusely distributed in myoblasts, became localized in myotubes in a distribution similar to that of the sarcomplasmic reticulum and T tubules. Later in development, lectin was predominantly extracellular. This sequence suggests that externalization may have occurred by migration in the T tubules, which are continuous with the extracellular space, although alternative explanations are possible. Only traces of lectin were found in the adult. These studies did not reveal the function of CLL-l in muscle development. It may act by organizing complementary glycoconjugates in the intracellular tubular network, on th muscle surface, and/or in extracellular materials.