Proteogylcan heterogeneity in embryonic chick articular and epiphyseal cartilages.

Proteoglycans from two regions of the chick limb rudiment (articular and epiphyseal) were examined for chemical microheterogeneity. These cartilages are composed of at least two series of proteoglycan variants whose glycosaminoglycan side chains display microheterogeneity with respect to the proportions of 4- and 6-linked ester sulfate. Other differences are noted which are consonant with the hypothesis that extracellular matrix components may be structurally adapted to a tissue's developmental fate or function.