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Monoclonal antibodies as tools in studying the differentiation of the dental mesenchyme
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PARTICIPATION OF Ca 2+ IN THE PLANT PHYTOCHRO~ MECHANISM A. Tretyn, Copernicus Univ.,Inst.Biology 87-100 Toru~, Poland The subject of the research was to ~nvestigate the infl~ence of red/R/ ~nd far red /FR/ light on Cag+uptake and its intracellular localization in oat coleoptile cells. It has been found that sections of oat ~ i o ~ t e d coleoptiles in darkness take up 'Ca ~from medium. The rate of uptake of the i6ns was increased after 15min exposure to R. The FR and calcium channel blockers neutralized the stimulative action of R. Reaction to potassium antimonate proved Cad+to accumulate on both sides of plasma membrane in cells of oat etlolated col~ooti~+~ les. Following 15min exwosure to R, Ca was localized mainly FR • in ER cisterns. ~+ . irradiation fol~owing R, caused Ca to dlsappear from ~ and then appear ~ s ~ d e plas~le~ma. The results of present work allow the following conclusion: a/R ag~ F~ affect plasmalenma permeability to Ca-'through regulation ~f calcium channels~ b/the localization of CaZ+in cells is regulated by the phytcchrome, c/in plant ce21s ~ perform a very important function connected with the a c c u m u l a t i o n and re~;ulation of the cytoplasmic Ca ~level, d/ehanmes in the localization of Ca llnked wlth ~he functionin~ of phytochrome may start deetiolation process.
T h ~ DETELOP~dENT OF T ~ R O I D GLAND OF C H I C K E N E~vBRYOS° S . T u i c h i e v , ~1oS.Musaev. T a s h k e n t A g r i c u l t u r a r y Institute,State Agro-Industl~,USSR. The functional and structural d e v e l o p m e n t of t h y r o i d g l a n d of c h i c k e n e m b r y o s was s t u d i e d by b i o chemical and morphological methods° It w a s s h o v m , t h a t the c e l l s of t ~ j r o i d g l a n d of c h i c k e n e m b ~ , o s a c c u m u l a t e d i o d i n e s i n c e the 8 - t h day of i n c u b a t i o n , b u t the s y n t h e s i s of i o d i n e a m i n o a c i d s s c a t t e d on tae 9 - t h day of the d e v e l o p m e n t of g l a n d at the l e v e l of t i ~ r o i d h o r mone precursors. T w o p e r i o d s w e r e r e v e a l e d in the f u n c t i o n a l a c t i v i t y of e m b r y o t h y roid gland:the first initial period (on the 1 0 - 1 1 - t h day) a1~d the s e c o n d one of i n c r e a s e d a c t i v i t y (on the 1 5 - 1 6 - t h day). ~he d i r e c t c o r r e l a t i o n b e t w e e n the d e v e l o p m e n t of e m b r y o t ~ r o i d s l a n d a n d its h o r m o n e - o r g a n i z e d f u n c t i o n was d e t e r m i n e d . T h e a p p e a r a n c e of i n t r a c e l l u l a r c o l l o i a . drops,~icrofollicles a n n ~ne b e g ! n n l n ~ o! s y n t h e s i s of h o r m o n e s c o i n c i d e w i t h the d i f f e r e n t i a t i o n of c e l l u l a r oz'ganoidso
266
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INCREASED PROOUCTION OF PLASMINOGEN ACTIVATOR AND GELATINASE BY DENTAL PAPILLA CELLS IN CULTURE. V.-J. Uitto and I. Thesleff, Institutes of Dentistry, University of Helsinki, SF-00280 Helsinki, Finland.
MONOCLONAL ANTIBODIES AS TOOLS IN STUDYING THE DIFFERENTIATION OF THE DENTAL MESENCHYME. S. Vainio, E. Lehtonen, M. Kaartinen and I. Thesleff. Institute of Dentistry and Departments of Pathology and Immunology, University of Helsinki, SF-00280 Helsinki,Finland. The dental papilla cells regulate the development of the tooth. The specificity of these cells results from interactions with the odontogenic epithelium, but the molecular basis of their determination is unknown. Our aim is to identify developmentally important molecules in the dental papilla. Dental papillae were separated from molar teeth of 17-day-old embryos by trypsin or EDTA treatment. They were fixed in paraformaldehyde (PFA) and sonicated or homogenized in saline. LOU rats were immunized with this antigen. Hybridomas were produced by standard methods. Supernatants were screened by immunohistology using both frozen sections and sections of PFA-fixed and paraffin embedded mouse molar teeth. Of the 400 wells screened one was studied more closely. This antibody recognizes a 67 kD intracellular component which is enriched in odontoblasts and ameloblasts and which may be associated with the secretory process in these cells.
The dental papilla cells play a major role in tooth morphogenesis. We have earlier found that these cells loose their fibronectin-rich matrix in culture. We studied here the production of plasminogen activator and gelatinolytic activity by cultured dental papilla cells and compared them with other mesenchymal cells isolated from jaws of 17-day-old mouse embryo. The results show that dental papilla cells secreted plasminogen activator during the entire culture period of 11 days. Proteolyric activity against gelatin increased linearily in medium during culture. The enzyme(s) existed part]y in a latent form and could be activated by the addition of aminophenylmercuric acetate to the assay. To some extent the activity could also be increased by the addition of plasminogen. The other mesenchymal cells under the same conditions produced little or no plasminogen activator or gelatinase. The results suggest that proteolytic enzymes may be important factors controlling morphogenesis and cell differentiation. 93S
PARTICIPATION OF Ca 2+ IN THE PLANT PHYTOCHRO~ MECHANISM A. Tretyn, Copernicus Univ.,Inst.Biology 87-100 Toru~, Poland The subject of the research was to ~nvestigate the infl~ence of red/R/ ~nd far red /FR/ light on Cag+uptake and its intracellular localization in oat coleoptile cells. It has been found that sections of oat ~ i o ~ t e d coleoptiles in darkness take up 'Ca ~from medium. The rate of uptake of the i6ns was increased after 15min exposure to R. The FR and calcium channel blockers neutralized the stimulative action of R. Reaction to potassium antimonate proved Cad+to accumulate on both sides of plasma membrane in cells of oat etlolated col~ooti~+~ les. Following 15min exwosure to R, Ca was localized mainly FR • in ER cisterns. ~+ . irradiation fol~owing R, caused Ca to dlsappear from ~ and then appear ~ s ~ d e plas~le~ma. The results of present work allow the following conclusion: a/R ag~ F~ affect plasmalenma permeability to Ca-'through regulation ~f calcium channels~ b/the localization of CaZ+in cells is regulated by the phytcchrome, c/in plant ce21s ~ perform a very important function connected with the a c c u m u l a t i o n and re~;ulation of the cytoplasmic Ca ~level, d/ehanmes in the localization of Ca llnked wlth ~he functionin~ of phytochrome may start deetiolation process.
T h ~ DETELOP~dENT OF T ~ R O I D GLAND OF C H I C K E N E~vBRYOS° S . T u i c h i e v , ~1oS.Musaev. T a s h k e n t A g r i c u l t u r a r y Institute,State Agro-Industl~,USSR. The functional and structural d e v e l o p m e n t of t h y r o i d g l a n d of c h i c k e n e m b r y o s was s t u d i e d by b i o chemical and morphological methods° It w a s s h o v m , t h a t the c e l l s of t ~ j r o i d g l a n d of c h i c k e n e m b ~ , o s a c c u m u l a t e d i o d i n e s i n c e the 8 - t h day of i n c u b a t i o n , b u t the s y n t h e s i s of i o d i n e a m i n o a c i d s s c a t t e d on tae 9 - t h day of the d e v e l o p m e n t of g l a n d at the l e v e l of t i ~ r o i d h o r mone precursors. T w o p e r i o d s w e r e r e v e a l e d in the f u n c t i o n a l a c t i v i t y of e m b r y o t h y roid gland:the first initial period (on the 1 0 - 1 1 - t h day) a1~d the s e c o n d one of i n c r e a s e d a c t i v i t y (on the 1 5 - 1 6 - t h day). ~he d i r e c t c o r r e l a t i o n b e t w e e n the d e v e l o p m e n t of e m b r y o t ~ r o i d s l a n d a n d its h o r m o n e - o r g a n i z e d f u n c t i o n was d e t e r m i n e d . T h e a p p e a r a n c e of i n t r a c e l l u l a r c o l l o i a . drops,~icrofollicles a n n ~ne b e g ! n n l n ~ o! s y n t h e s i s of h o r m o n e s c o i n c i d e w i t h the d i f f e r e n t i a t i o n of c e l l u l a r oz'ganoidso
266
267
INCREASED PROOUCTION OF PLASMINOGEN ACTIVATOR AND GELATINASE BY DENTAL PAPILLA CELLS IN CULTURE. V.-J. Uitto and I. Thesleff, Institutes of Dentistry, University of Helsinki, SF-00280 Helsinki, Finland.
MONOCLONAL ANTIBODIES AS TOOLS IN STUDYING THE DIFFERENTIATION OF THE DENTAL MESENCHYME. S. Vainio, E. Lehtonen, M. Kaartinen and I. Thesleff. Institute of Dentistry and Departments of Pathology and Immunology, University of Helsinki, SF-00280 Helsinki,Finland. The dental papilla cells regulate the development of the tooth. The specificity of these cells results from interactions with the odontogenic epithelium, but the molecular basis of their determination is unknown. Our aim is to identify developmentally important molecules in the dental papilla. Dental papillae were separated from molar teeth of 17-day-old embryos by trypsin or EDTA treatment. They were fixed in paraformaldehyde (PFA) and sonicated or homogenized in saline. LOU rats were immunized with this antigen. Hybridomas were produced by standard methods. Supernatants were screened by immunohistology using both frozen sections and sections of PFA-fixed and paraffin embedded mouse molar teeth. Of the 400 wells screened one was studied more closely. This antibody recognizes a 67 kD intracellular component which is enriched in odontoblasts and ameloblasts and which may be associated with the secretory process in these cells.
The dental papilla cells play a major role in tooth morphogenesis. We have earlier found that these cells loose their fibronectin-rich matrix in culture. We studied here the production of plasminogen activator and gelatinolytic activity by cultured dental papilla cells and compared them with other mesenchymal cells isolated from jaws of 17-day-old mouse embryo. The results show that dental papilla cells secreted plasminogen activator during the entire culture period of 11 days. Proteolyric activity against gelatin increased linearily in medium during culture. The enzyme(s) existed part]y in a latent form and could be activated by the addition of aminophenylmercuric acetate to the assay. To some extent the activity could also be increased by the addition of plasminogen. The other mesenchymal cells under the same conditions produced little or no plasminogen activator or gelatinase. The results suggest that proteolytic enzymes may be important factors controlling morphogenesis and cell differentiation. 93S