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Reactivation of Xenopus erythrocyte nucleus in mouse oocyte
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'PISSUE-SPECIFIC R E G U L A T O N OF A CHICKEN O-CRYSTALLIN GENE I N T R O D U C E D IN i~IOUSE CELLS. H i s a t o Konoon, Snigeo Hayasni, YostliKo T a k a n a s n i ana T.S. OKaOa Dept. OL ~iopnysics, Faculty of Science, Kyoto university, Kyoto 60b, Japan ~e nave shown wttn transient expression a s s a y that a clone<] 6 - c r y s t a l i l n gene of c n l c K e n is p ~ e f e r e n t i a l l y exp r e s s e Q in lens w h e n i n t r o d u c e Q into mouse ceils, ano this tissue-tropism is aepenuent upon tt~e 30 up region locate~ u p s t r e a m o t tile cap site. v~e silow []ere that t~]Is 5' f l a n k i n g s e q u e n c e d i r e c t s the gene expression in a narrow range of t i s s u e s c l o s e l y r e l a t e o to lens in the pathways of ~itrerentiation, suggesting a t r a n s - a c t i n g m e c n a n i s m ~ue to cell ~ifierentiation. In other tissues, a low-level expression takes p l a c e w h i c h is ~epen~ent upon a lurtner upstream DNA sequence. ~itn 0-crystallin genes staOiy integ r a t e o ill a m o u s e c h r o m o s o m e , tile gene expressiot] was r e s t r i c t e o to ~]efined tissues which are characteristic to each c h r o m o s o m a l locus, itlds, a ClS--dCtlllg mechanism is a l s o i n v o l v e u in t n e tissue-speclfic 9ene regulation.
DISTRIBUTION OF DNA POLYMERASE CK AND IN VARIOUS CHICK TISSUE CELLS DURING DEVELOPMENT. Y. Koshida, H. Kitani, A. Matsukage and T. Morita. Department of Biology, Collegeof General Education, Osaka University, Toyonaka, Osaka, 560 and Aichi Cancer Center Research Institute, Nagoya, 464 Japan. Matsukage et al. prepared mouse monoclonal antibodies against chick embryo DNA polymerase C~ (1982) and a specific rabbit antibody against chick embryo DNA polymerase B (1982). Using these antibodies, DNA polymerase C~ and g were detected in cells of the chick neural retina, spinal cord, intestinal epithelium and testis during development. After fixation in 3.5% formaldehyde and embedding in polyester wax, thematerials were sectioned at 4pm and stained by indirect immunofluorescent methods with the above antibodies. DNA replicating cells were detected by ARG using aH-thymidine. Imm u n o f l u o r e s c e n c e w i t h a n t i - D N A polymerase , but not with anti-DNA polymerase ~, decreased abruptly in the nuclei of the celts which have just differentiated. Concomitantly with the disappearance of DNA polymeraseC~, cells may lose the DNA replication capacity.
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REACTIVATION OF XENOPUS ERYTI{ROCYTE NUCLEUS IN MOUSE OOCYTE. T.Y. Lu, S.G. Li, Y.L. Fen, R.Z. Zhen$, M. Tu, Institute of Developmental Biology, Academia Sinica, Beijing, People's Republic of China. Erythrocyte nuclei from cardic blood of adult Xenopus were micro-injected into the cytoplasm of diplotene oocytes of mouse; the injected oocytes were then cultured in vitro for maturing at varied hours. Most of the erythrocytes were reactivated; the nuclei became larger, decondensed and some of them transformed into condensed chromosomes. These results indicated that the cytoplasm of meiotic oocytes of mouse, just like those of amphibian, also contains the factors which can reactivate the nucleus of terminally differentiated erythrocyte. It is also revealed that these fa-tors have no species-specific effects in nature.
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ESTABLISHMENT OF AN A P I C A L PLASMA MEMBRANE DOMAIN PRIOR TO THE FORMATION OF TIGHT ]UNCTIONS DURING DEVELOPMENT OF THE MAMMALIAN P A N C R E A S . M.E. Madden and M.P. S a r r a s 3r. Dept. of A n a t o m y / D i v . of C e l l Biology, Univ. of Kansas M e d i c a l Center, Kansas City, KS, 66103. The role of tight junctions (zonula occludens) in the formation of apical plasma
m e m b r a n e (PM) domains was i n v e s t i g a t e d in t h e e m b r y o n i c r a t p a n c r e a s . In the p r e s e n t study, lectin-rhodamine and Iectin-gold c o n j u g a t e s w e r e used to monitor a p i c a l PM domain formation and freeze-fracture analysis was used to monitor tight junction formation in the pancreatic epithelium of embryonic and adult rats. Our results indicate that an apical PM domain is formed as early as day 13 of gestation in pancreatic epithelium and is maintained into adult life, In contrast, tight junctions are not completely formed until day 15-17 of gestation, At 14 days of gestation, sealing strands of tight junctions begin to form but are not continuous, These results suggest that lateral diffusion of PM glycoconjugates may be restricted even in the absence of complete tight junctional complexes, (Supported by NIH grant #AM33362 awarded to MPS)
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'PISSUE-SPECIFIC R E G U L A T O N OF A CHICKEN O-CRYSTALLIN GENE I N T R O D U C E D IN i~IOUSE CELLS. H i s a t o Konoon, Snigeo Hayasni, YostliKo T a k a n a s n i ana T.S. OKaOa Dept. OL ~iopnysics, Faculty of Science, Kyoto university, Kyoto 60b, Japan ~e nave shown wttn transient expression a s s a y that a clone<] 6 - c r y s t a l i l n gene of c n l c K e n is p ~ e f e r e n t i a l l y exp r e s s e Q in lens w h e n i n t r o d u c e Q into mouse ceils, ano this tissue-tropism is aepenuent upon tt~e 30 up region locate~ u p s t r e a m o t tile cap site. v~e silow []ere that t~]Is 5' f l a n k i n g s e q u e n c e d i r e c t s the gene expression in a narrow range of t i s s u e s c l o s e l y r e l a t e o to lens in the pathways of ~itrerentiation, suggesting a t r a n s - a c t i n g m e c n a n i s m ~ue to cell ~ifierentiation. In other tissues, a low-level expression takes p l a c e w h i c h is ~epen~ent upon a lurtner upstream DNA sequence. ~itn 0-crystallin genes staOiy integ r a t e o ill a m o u s e c h r o m o s o m e , tile gene expressiot] was r e s t r i c t e o to ~]efined tissues which are characteristic to each c h r o m o s o m a l locus, itlds, a ClS--dCtlllg mechanism is a l s o i n v o l v e u in t n e tissue-speclfic 9ene regulation.
DISTRIBUTION OF DNA POLYMERASE CK AND IN VARIOUS CHICK TISSUE CELLS DURING DEVELOPMENT. Y. Koshida, H. Kitani, A. Matsukage and T. Morita. Department of Biology, Collegeof General Education, Osaka University, Toyonaka, Osaka, 560 and Aichi Cancer Center Research Institute, Nagoya, 464 Japan. Matsukage et al. prepared mouse monoclonal antibodies against chick embryo DNA polymerase C~ (1982) and a specific rabbit antibody against chick embryo DNA polymerase B (1982). Using these antibodies, DNA polymerase C~ and g were detected in cells of the chick neural retina, spinal cord, intestinal epithelium and testis during development. After fixation in 3.5% formaldehyde and embedding in polyester wax, thematerials were sectioned at 4pm and stained by indirect immunofluorescent methods with the above antibodies. DNA replicating cells were detected by ARG using aH-thymidine. Imm u n o f l u o r e s c e n c e w i t h a n t i - D N A polymerase , but not with anti-DNA polymerase ~, decreased abruptly in the nuclei of the celts which have just differentiated. Concomitantly with the disappearance of DNA polymeraseC~, cells may lose the DNA replication capacity.
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326
REACTIVATION OF XENOPUS ERYTI{ROCYTE NUCLEUS IN MOUSE OOCYTE. T.Y. Lu, S.G. Li, Y.L. Fen, R.Z. Zhen$, M. Tu, Institute of Developmental Biology, Academia Sinica, Beijing, People's Republic of China. Erythrocyte nuclei from cardic blood of adult Xenopus were micro-injected into the cytoplasm of diplotene oocytes of mouse; the injected oocytes were then cultured in vitro for maturing at varied hours. Most of the erythrocytes were reactivated; the nuclei became larger, decondensed and some of them transformed into condensed chromosomes. These results indicated that the cytoplasm of meiotic oocytes of mouse, just like those of amphibian, also contains the factors which can reactivate the nucleus of terminally differentiated erythrocyte. It is also revealed that these fa-tors have no species-specific effects in nature.
130S
ESTABLISHMENT OF AN A P I C A L PLASMA MEMBRANE DOMAIN PRIOR TO THE FORMATION OF TIGHT ]UNCTIONS DURING DEVELOPMENT OF THE MAMMALIAN P A N C R E A S . M.E. Madden and M.P. S a r r a s 3r. Dept. of A n a t o m y / D i v . of C e l l Biology, Univ. of Kansas M e d i c a l Center, Kansas City, KS, 66103. The role of tight junctions (zonula occludens) in the formation of apical plasma
m e m b r a n e (PM) domains was i n v e s t i g a t e d in t h e e m b r y o n i c r a t p a n c r e a s . In the p r e s e n t study, lectin-rhodamine and Iectin-gold c o n j u g a t e s w e r e used to monitor a p i c a l PM domain formation and freeze-fracture analysis was used to monitor tight junction formation in the pancreatic epithelium of embryonic and adult rats. Our results indicate that an apical PM domain is formed as early as day 13 of gestation in pancreatic epithelium and is maintained into adult life, In contrast, tight junctions are not completely formed until day 15-17 of gestation, At 14 days of gestation, sealing strands of tight junctions begin to form but are not continuous, These results suggest that lateral diffusion of PM glycoconjugates may be restricted even in the absence of complete tight junctional complexes, (Supported by NIH grant #AM33362 awarded to MPS)