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Study on the importance of keratin in Xenopus early embryos
Cell Biology
International
P377
PHENOTYPIC LIFERATION CELLS
Reports,
Vol. 14, Abstracts
CHANGES
PRIOR
IN PRIMORDIAL
OF THE
COMMON
TO PRO-
Supplement
7990
THE DEVELOPkIEN!l! OP klARINE NEMATODA ENOPLUS &REVIS
P378
GERM CARP
173
Dmitrey
A.Voronov, Helen P.Makaren.kotra, Leonid P.Nezlin, Jurey V.Panchin, Sergius E.Spiridonov. Zoological Institute Academy of Scien tea of the USSR. Leninarad 199034.USSR: Institute for Problem of Info%tion ' Transmission Academy of Sciences of the USSR, MOBCOW101447, USSR. The progeni of blaatomeres at two -
Aart van Winkoop, John Dulos, Lucy P.M. Timmermans Department of Exp. Animal Morphology and Cell Biology, Agricultural University, P.O. Box 338, 6700 AH Wageningen, The Netherlands. A ciescription is given of primordial germ cell (PGC) differentiation in carp (Cvprinus Carpio L.. Teleostei) from hatching until the* age of six’ weeks: uring that period the PGCs are mitotically ;;;;;;$I9 their phenotype changes considerably. Thus, conc:mittantly with a distinct increase in size of the cells the perinuclear dense bodies increase in size and form the ‘cement’ between mitochondria. In addition, a cell surface marker defined by the monoclonal antibody WCG 6 is gradually expressed on the surface membrane. It is concluded that these changes, which are completed in most PGCs at the age of four weeks, reflect the preparation for the fast proliferation which occurs after six weeks. An active role of PGC surface molecules in the regulation of proliferation is suggested from recent data showing that treatments of larvae with pituitary factors advance PGC proliferation. 1) Parmentier, H.K.; Timmermans, L.P.M.; J. Embryol. Exp. Morphol. 90 (1985).
eight-cell stages wa8 inveetigated by intracellular Injection of fluorescent dyeer and Horserhadsh Peroxidase. At twocell stages the fates of blaetomerea are not determined. In different experiments the progeai of each of the two blastome-
P379
P380
STUDY ON TllE 1!4'ORTANCE C'F KI%'ITIN IN XENOPUS EARLY EMBRYOS Xie Jinguu%Yu Haojian .Dept of Biolow,pekinr! Univ Beijing .tiinghai College of Aniwi Husbandry & Vet Biological Lab.Xining. P R China. Antikeratin Mb AF5 was microinjected into the fertilized eggs of Xenopus laevrs.Surviv31 rele of the experiment is much louer(3Z82 at g&rulae )
Lhan the control (74.9% at trastrulae,dono b,- in&tillg sheep anti-mom antibody It& ) .t&t of the survivors in the experiment are-teratogi,:aI and the embryos
are mostly
Hiroin.lecting
keratin-negative
just one ccl I at 2-cell
one cell developed while another cell
at bbtula.
embrun ,only
normally and is keratin-positive died after microin.iecl:ic:n.We
SUE-
gest Lhat keratins in early embryos arc indispensable for embryonic development.
res may occupy different postions in the embrio. However at eight-blastomere stages a single blastomere gives rise to the complete endoderm. Whereaa the fates of others are varyable. In spite of the lack of a rigid determination in early embrioaenesis. the resultina larva has a constant cell-composition iG some parts of it.% body: at least in the head and tail hypode-%, in the sensory organs and in the catecholamine neurona. It is interesting, that the larva Enoplus brevis and Caenorhabdtia elegans are very similar. Wherease the development is strictly determined later.
TRANSCRIPTIONAL FACTORS IN DEVELOPMENTAL MECHANISM OF55 rRNA GENES EXPRESSION IN FISH
M. Timofeeva,P. Felgenhauer,P. Shostak,I. Sedman,A.
Bayev, Lind, W. Engelh&dt Institute of Molecular Biology, the USSR Academy of Sciences, Vavilov str.32, Moscow, 117984, USSR; N. Koltzov Inst. of Developmental Biology, the USSR Academy of Sciences, Vavilov str.26, Moscow, 117984, USSR; Estonian Biocentre, Estonian Academy of Sciences, Kingissepa
14/16,Tanu,202400Estonia.
Deletion mutants of loach oocyte 5S rRNA genes were injected and transcribed in vivo in the nuclei of the loach Misgurnus fossilis and frog Xenopus laevis. A control region was found in the S-flanking sequence, the elimination of which greatly decreases the in vivo transcription of 55 RNA genes. This cisacting element is located in the region between nt-18 and the transcriptional start point. We propose that the oocyte nucleus contains a specific transcriptional factor(s), NTFO which interacts with the cis-acting element we described. We also propose that NFTO is inactivated in maturing oocytes when nucleoplasm interacts with oocyte cytoplasm after vesicle breakdown. The residual activity of this factor(s) may be responsible for the low level of oocytes 5S rRNA synthesis in the early embryogenesis. Apparently the disappearance of NTFO during gastrulation seems to be responsible for the total inactivation of occyte 5S rRNA genes in the embryonic and somatic tissue.
International
P377
PHENOTYPIC LIFERATION CELLS
Reports,
Vol. 14, Abstracts
CHANGES
PRIOR
IN PRIMORDIAL
OF THE
COMMON
TO PRO-
Supplement
7990
THE DEVELOPkIEN!l! OP klARINE NEMATODA ENOPLUS &REVIS
P378
GERM CARP
173
Dmitrey
A.Voronov, Helen P.Makaren.kotra, Leonid P.Nezlin, Jurey V.Panchin, Sergius E.Spiridonov. Zoological Institute Academy of Scien tea of the USSR. Leninarad 199034.USSR: Institute for Problem of Info%tion ' Transmission Academy of Sciences of the USSR, MOBCOW101447, USSR. The progeni of blaatomeres at two -
Aart van Winkoop, John Dulos, Lucy P.M. Timmermans Department of Exp. Animal Morphology and Cell Biology, Agricultural University, P.O. Box 338, 6700 AH Wageningen, The Netherlands. A ciescription is given of primordial germ cell (PGC) differentiation in carp (Cvprinus Carpio L.. Teleostei) from hatching until the* age of six’ weeks: uring that period the PGCs are mitotically ;;;;;;$I9 their phenotype changes considerably. Thus, conc:mittantly with a distinct increase in size of the cells the perinuclear dense bodies increase in size and form the ‘cement’ between mitochondria. In addition, a cell surface marker defined by the monoclonal antibody WCG 6 is gradually expressed on the surface membrane. It is concluded that these changes, which are completed in most PGCs at the age of four weeks, reflect the preparation for the fast proliferation which occurs after six weeks. An active role of PGC surface molecules in the regulation of proliferation is suggested from recent data showing that treatments of larvae with pituitary factors advance PGC proliferation. 1) Parmentier, H.K.; Timmermans, L.P.M.; J. Embryol. Exp. Morphol. 90 (1985).
eight-cell stages wa8 inveetigated by intracellular Injection of fluorescent dyeer and Horserhadsh Peroxidase. At twocell stages the fates of blaetomerea are not determined. In different experiments the progeai of each of the two blastome-
P379
P380
STUDY ON TllE 1!4'ORTANCE C'F KI%'ITIN IN XENOPUS EARLY EMBRYOS Xie Jinguu%Yu Haojian .Dept of Biolow,pekinr! Univ Beijing .tiinghai College of Aniwi Husbandry & Vet Biological Lab.Xining. P R China. Antikeratin Mb AF5 was microinjected into the fertilized eggs of Xenopus laevrs.Surviv31 rele of the experiment is much louer(3Z82 at g&rulae )
Lhan the control (74.9% at trastrulae,dono b,- in&tillg sheep anti-mom antibody It& ) .t&t of the survivors in the experiment are-teratogi,:aI and the embryos
are mostly
Hiroin.lecting
keratin-negative
just one ccl I at 2-cell
one cell developed while another cell
at bbtula.
embrun ,only
normally and is keratin-positive died after microin.iecl:ic:n.We
SUE-
gest Lhat keratins in early embryos arc indispensable for embryonic development.
res may occupy different postions in the embrio. However at eight-blastomere stages a single blastomere gives rise to the complete endoderm. Whereaa the fates of others are varyable. In spite of the lack of a rigid determination in early embrioaenesis. the resultina larva has a constant cell-composition iG some parts of it.% body: at least in the head and tail hypode-%, in the sensory organs and in the catecholamine neurona. It is interesting, that the larva Enoplus brevis and Caenorhabdtia elegans are very similar. Wherease the development is strictly determined later.
TRANSCRIPTIONAL FACTORS IN DEVELOPMENTAL MECHANISM OF55 rRNA GENES EXPRESSION IN FISH
M. Timofeeva,P. Felgenhauer,P. Shostak,I. Sedman,A.
Bayev, Lind, W. Engelh&dt Institute of Molecular Biology, the USSR Academy of Sciences, Vavilov str.32, Moscow, 117984, USSR; N. Koltzov Inst. of Developmental Biology, the USSR Academy of Sciences, Vavilov str.26, Moscow, 117984, USSR; Estonian Biocentre, Estonian Academy of Sciences, Kingissepa
14/16,Tanu,202400Estonia.
Deletion mutants of loach oocyte 5S rRNA genes were injected and transcribed in vivo in the nuclei of the loach Misgurnus fossilis and frog Xenopus laevis. A control region was found in the S-flanking sequence, the elimination of which greatly decreases the in vivo transcription of 55 RNA genes. This cisacting element is located in the region between nt-18 and the transcriptional start point. We propose that the oocyte nucleus contains a specific transcriptional factor(s), NTFO which interacts with the cis-acting element we described. We also propose that NFTO is inactivated in maturing oocytes when nucleoplasm interacts with oocyte cytoplasm after vesicle breakdown. The residual activity of this factor(s) may be responsible for the low level of oocytes 5S rRNA synthesis in the early embryogenesis. Apparently the disappearance of NTFO during gastrulation seems to be responsible for the total inactivation of occyte 5S rRNA genes in the embryonic and somatic tissue.