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Ontogeny of creatine kinase isozymes in fish embryo; immunofluorescent localization in differentiating retina cells
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Differentiated Domains of the Hepatocyte Surface. J.R. Bartles, L.T. Braiterman and A.L. Hubbard. Dept. of Cell Biology and Anatomy, The Johns Hopkins Univ. Sch. of Medicine, Baltimore, MD 21205, USA. We have raised monoclonal antibodies to integral sialoglycoproteins of the rat hepatocyte plasma membrane (PM) and have localized the proteins on sections of rat liver tissue using immunofluorescence and electron microscope-immunoperoxidase. Four of the proteins exhibit specific distributions about the hepatocyte surface: one is localized to the bile canalicular (BC) domain, and three are localized to both the sinusoidal (SF) and lateral (LS) domains. A fifth protein is present in all three domains. By immunog01d labeling, we have shown that two of the proteins retain mutually exclusive domain localizations on isolated hepatocyte PMs. We have used these two proteins as domain markers to monitor the separation of PM vesicles derived from BC and SF/LS domains in sucrose density gradients and to make domain assignments for several other PM antigens and enzyme activities. We are currently investigating the fates of these proteins during liver regeneration. (Supported by the NIH.)
THE SYNTHESIS OF SPICULE MATRIX GLYCOPROTEINS OF SEA URCHIN EMBRYOS. S. Benson, N. Benson and F. Wilt. Department of Zoology, University of California, Berkeley and Department of Biology, California State Univ., Hayward. The primary mesenchyme cells of sea urchin embryos are derived from micromeres and produce the calcareous endoske]etal spicules of the pluteus larva. We have purified the spicules and characterized the predominant spicule matrix glycoproteins. They are a family of acidic proteins rich in asp, g]u and gly. Immunochemica] studies show that the glycoproteins appear in the spicule as it is constructed. A DNA sequence has been isolated and partially characterized that encodes the predominant 55 kd glycoprotein of the matrix. Spicule formation and the expression of this gene may now serve as a basis to study determination and differentiation of the primary mesenchyme ceils.
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DIFFERENTIAL GENE EXPRESSION OF ENAMELINS AND AMELOGENINS DURING MOUSE MOLAR TOOTH ORGANOGENESIS. C.Bessem, P.Brings,Jr. and H.C. Slavkin. Lab. Develop. Biol., School of Dentistry, Univ. Southern California, Los Angeles, Calif. 90089-0191. The ameloblast biochemical phenotype is represented by a suggested multigene family of enamel proteins. The enamelin subfamily are acidic glycoproteins, the amelogenin subfamily are proline-rich, hydrophobic polypeptides. Enamel proteins appear to share antigenic determinants. Present studies were designed to ascertain if both enamelins and amelogenins were expressed at the same deve]opmental stage of mouse tooth organogenesis. We used several criteria for detection including immunoreactivity, relative molecular weight and isoelectric focusing. Biosynthetic studies used 35Smethionine. Mandibular first molar tooth organs were obtained from cap (circa 16days gestation) through crown formation stages (4-days postnatal). Analyses of results indicate enamelin polypeptides were detected 24 hours before amelogenins and prior to histn]ogica] detection of secretory ame]oblasts. Supported by research grants DE-02848 and DE-06425.
ONTOGENY OF CREATINE KINASE ISOZYMES IN FISH EMBRYO;IMMUNOFLUORESCENT LOCALIZATION IN DIFFERENTIATING RETINA CELLS. H.Boulekbache,Ci.Joly,Th. Darrib6re,J.C. Boucaut and A.Feghali.Laboratoire de Biologie du D6veloppement,Universit6 Paris 7 2 place Jussieu,F-75251 PARIS 05 and Laboratoire de Biologie Exp6rimentale, Universit6 Ren6 Descartes,45 rue des StsP6res,75270 PARIS 06, FRANCE. Creatine Kinase (CK:EC.2.7.3.2) isozymes of trout were purified by affinity chromatography and preparative electropho resis. Specific antibodies anti-CK were prepared in rabbit. Electrostarch gels, polyacrylamide gels and immunoblotting of trout embryos and retina cells were carried out. Izmmunofluorescent localization of CK in pre and post hatching trout embryos shows that CK isozymes are visualized in only two cell layers during the differentiation of trout retina:the photo receptor cells and the external plexiform layer. The presence of CK in cones, rods and external plexiform cell layer could be explained by ATP regeneration (Lohman' s reaction) and plasticity of pedicules which requires the display of microtubules and microfilaments. Research
126S
support
: M.E.N.
(C.C 1984]
308
Differentiated Domains of the Hepatocyte Surface. J.R. Bartles, L.T. Braiterman and A.L. Hubbard. Dept. of Cell Biology and Anatomy, The Johns Hopkins Univ. Sch. of Medicine, Baltimore, MD 21205, USA. We have raised monoclonal antibodies to integral sialoglycoproteins of the rat hepatocyte plasma membrane (PM) and have localized the proteins on sections of rat liver tissue using immunofluorescence and electron microscope-immunoperoxidase. Four of the proteins exhibit specific distributions about the hepatocyte surface: one is localized to the bile canalicular (BC) domain, and three are localized to both the sinusoidal (SF) and lateral (LS) domains. A fifth protein is present in all three domains. By immunog01d labeling, we have shown that two of the proteins retain mutually exclusive domain localizations on isolated hepatocyte PMs. We have used these two proteins as domain markers to monitor the separation of PM vesicles derived from BC and SF/LS domains in sucrose density gradients and to make domain assignments for several other PM antigens and enzyme activities. We are currently investigating the fates of these proteins during liver regeneration. (Supported by the NIH.)
THE SYNTHESIS OF SPICULE MATRIX GLYCOPROTEINS OF SEA URCHIN EMBRYOS. S. Benson, N. Benson and F. Wilt. Department of Zoology, University of California, Berkeley and Department of Biology, California State Univ., Hayward. The primary mesenchyme cells of sea urchin embryos are derived from micromeres and produce the calcareous endoske]etal spicules of the pluteus larva. We have purified the spicules and characterized the predominant spicule matrix glycoproteins. They are a family of acidic proteins rich in asp, g]u and gly. Immunochemica] studies show that the glycoproteins appear in the spicule as it is constructed. A DNA sequence has been isolated and partially characterized that encodes the predominant 55 kd glycoprotein of the matrix. Spicule formation and the expression of this gene may now serve as a basis to study determination and differentiation of the primary mesenchyme ceils.
309
310
DIFFERENTIAL GENE EXPRESSION OF ENAMELINS AND AMELOGENINS DURING MOUSE MOLAR TOOTH ORGANOGENESIS. C.Bessem, P.Brings,Jr. and H.C. Slavkin. Lab. Develop. Biol., School of Dentistry, Univ. Southern California, Los Angeles, Calif. 90089-0191. The ameloblast biochemical phenotype is represented by a suggested multigene family of enamel proteins. The enamelin subfamily are acidic glycoproteins, the amelogenin subfamily are proline-rich, hydrophobic polypeptides. Enamel proteins appear to share antigenic determinants. Present studies were designed to ascertain if both enamelins and amelogenins were expressed at the same deve]opmental stage of mouse tooth organogenesis. We used several criteria for detection including immunoreactivity, relative molecular weight and isoelectric focusing. Biosynthetic studies used 35Smethionine. Mandibular first molar tooth organs were obtained from cap (circa 16days gestation) through crown formation stages (4-days postnatal). Analyses of results indicate enamelin polypeptides were detected 24 hours before amelogenins and prior to histn]ogica] detection of secretory ame]oblasts. Supported by research grants DE-02848 and DE-06425.
ONTOGENY OF CREATINE KINASE ISOZYMES IN FISH EMBRYO;IMMUNOFLUORESCENT LOCALIZATION IN DIFFERENTIATING RETINA CELLS. H.Boulekbache,Ci.Joly,Th. Darrib6re,J.C. Boucaut and A.Feghali.Laboratoire de Biologie du D6veloppement,Universit6 Paris 7 2 place Jussieu,F-75251 PARIS 05 and Laboratoire de Biologie Exp6rimentale, Universit6 Ren6 Descartes,45 rue des StsP6res,75270 PARIS 06, FRANCE. Creatine Kinase (CK:EC.2.7.3.2) isozymes of trout were purified by affinity chromatography and preparative electropho resis. Specific antibodies anti-CK were prepared in rabbit. Electrostarch gels, polyacrylamide gels and immunoblotting of trout embryos and retina cells were carried out. Izmmunofluorescent localization of CK in pre and post hatching trout embryos shows that CK isozymes are visualized in only two cell layers during the differentiation of trout retina:the photo receptor cells and the external plexiform layer. The presence of CK in cones, rods and external plexiform cell layer could be explained by ATP regeneration (Lohman' s reaction) and plasticity of pedicules which requires the display of microtubules and microfilaments. Research
126S
support
: M.E.N.
(C.C 1984]