Location and identification of the collagen found in the 14.5-d rat embryo visceral yolk sac.
The collagens associated with 14.5-d rat visceral yolk sacs were localized and identified by a variety of procedures. Morphological examination showed that both the visceral epithelium and mesothelium rested upon thin basement membranes, whereas the majority of the extracellular matrix consisted of a stroma containing occasional cells and abundant banded fibrils. Immunohistochemistry at the electron microscope level showed that the basement membranes specifically cross-reacted with antibodies directed against mouse basement membrane components, whereas the stroma specifically cross-reacted with antibodies directed against rat type I collagen. Extractions of acellular visceral yolk sacs and subsequent analyses showed that type I collagen components were prevalent. Furthermore, in vitro biosynthetic studies showed only the presence of type I procollagen components (or their conversion products) and alpha-fetoprotein. These findings, taken together with our previous studies on the 14.5-d rat parietal yolk sac, provide us with protein markers for studying the origin of cells in rat parietovisceral yolk sac carcinomas.
D000818:Animals; D001485:Basement Membrane / Q000032:analysis; D003094:Collagen / Q000032:analysis* / Q000302:isolation & purification; D003238:Connective Tissue / Q000032:analysis*; D004848:Epithelium / Q000648:ultrastructure; D008566:Membranes / Q000032:analysis; D008854:Microscopy, Electron; D011347:Procollagen / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D015017:Yolk Sac / Q000032:analysis* / Q000378:metabolism / Q000648:ultrastructure
D011347:Procollagen; D003094:Collagen