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1.
Int J Dev Biol ; 61(1-2): 1-3, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28287240

RESUMO

Professor Andrzej Krzysztof Tarkowski passed away last September (2016) at the age of 83. His findings, have become indispensable tools for immunological, genetic, and oncological studies, as well as for generating transgenic animals which are instrumental for studying gene function in living animals. His work and discoveries provided a tremendous input to the contemporary developmental biology of mammals.


Assuntos
Biologia do Desenvolvimento/história , História do Século XX , História do Século XXI , Polônia
2.
Biol Reprod ; 75(4): 582-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16822899

RESUMO

The second cleavage of the mouse embryo is asynchronous. Some recent investigators have proposed that the sequence of division of blastomeres in two-cell embryos may predict the ultimate location of the descendants of these blastomeres within the blastocyst. To verify this model, we tracked the cells derived from two-cell stage blastomeres using tetramethylrhodamine-conjugated dextran as a lineage tracer. In the first variant of the experiment, we labeled one of two blastomeres in two-cell embryos and subsequently recorded which blastomere cleaved first. In the second variant of the experiment, fluorescent dextran was injected at the three-cell stage into the blastomere that had not yet cleaved. Subsequently, the fate of the progeny of labeled and unlabeled blastomeres was followed up to the blastocyst stage. Our results suggest that allocation of cells into the embryonic and abembryonic parts of the blastocyst is not determined by the order of cleavage of the first two blastomeres.


Assuntos
Blastocisto/citologia , Blastômeros/citologia , Fase de Clivagem do Zigoto , Animais , Linhagem da Célula , Fase de Clivagem do Zigoto/efeitos dos fármacos , Dextranos/farmacologia , Feminino , Camundongos , Camundongos Endogâmicos
3.
Mol Reprod Dev ; 72(3): 362-76, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16094614

RESUMO

Spontaneous diploid-triploid chimaeras occur sporadically in various mammalian species including man, but so far have never been produced experimentally. In order to get a deeper insight into the developmental consequences of this anomaly, we have developed two procedures that enabled for the first time to produce routinely diploid-triploid embryos, foetuses, and animals in the mouse. These procedures are: (1) aggregation of cleaving diploid embryos with triploid embryos produced by suppression of the second polar body in zygotes, and (2) fusion of a haploid karyoplast with one blastomere of the two-cell diploid embryos. The first procedure yielded 23 living and 6 dead postimplantation embryos and foetuses (age: 8th-19th day) out of which 22 were chimaeric. In addition, three chimaeric neonates reached adulthood. Two animals were fertile, and one--an overt chimaera--was an infertile male. The rate of postimplantation development of aggregation chimaeras was normal or only slightly retarded, and with one exception the foetuses were morphologically normal. Generally, the highest contribution of the 3n component in extra-embryonic structures was noted in the yolk sac, and usually it was higher than its contribution to the organs of the body. Chimaerism was most often noted in the liver, the heart, the intestine, and the lungs. Participation of triploid cells to all tissues studied, both in the body and in extra-embryonic structures, appeared to decrease slightly as development progressed. The second procedure yielded 10 foetuses and 6 adults. Three foetuses were chimaeric. Six fertile adults were probably non-chimaeras: the triploid component was absent in the coat and in the blood.


Assuntos
Quimera/crescimento & desenvolvimento , Quimera/genética , Técnicas de Cultura Embrionária/métodos , Desenvolvimento Embrionário/fisiologia , Modelos Animais , Poliploidia , Animais , Agregação Celular/fisiologia , Transferência Embrionária , Hibridização in Situ Fluorescente , Camundongos
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