Sulfated glycosaminoglycan deposition and processing at the basal epithelial surface in branching and β- d-xyloside-inhibited embryonic salivary glands

Abstract

We investigated whether the inhibition of proteoglycan synthesis and salivary branching morphogenesis by β- d-xyloside was related to the deposition and processing of newly synthesized glycosaminoglycans at the basal epithelial surface that correlates with normal branching activity. Forty eight-hour cultures of control and 0.5 m M β-xyloside-treated submandibular rudiments were labeled for 2 hr with [ 35S]sulfate and fixed and processed for autoradiography, immediately or after 2, 4, 6, or 8 hr of postlabeling chase in nonradioactive medium. The data demonstrated that deposition of chondroitin sulfate-rich material at the basal epithelial surface was strikingly reduced in β-xyloside-treated rudiments, while patterns of label loss during postlabeling chase were not altered.