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Biomedical subjects

A Garcia-Bellido

Publications and source records attributed to A Garcia-Bellido.

16 recordsLinked to original sources
PubMed1989

The cellular interphase.

A brief outline is given of the impact of molecular genetics on the study of morphogenesis. Two approaches have been used, one beginning at the molecular level and applying knowledge gained in this way to observations of whole organisms; the other starting with descriptions of the organism and tracing the causes of developmental changes to cellular and then molecular events. The availability of experimentally induced mutants has facilitated the study of development, but such work must be combined with detailed information on the normal process. Comparative studies have exploited evolutionary conservation to identify functionally important gene activities, and allowed knowledge gained from one organism to be rapidly applied to other species. The successes achieved at the molecular level are impressive, but the time has come to return to studying the cells that are the real mediators of the transmission of the genetic information.

Animals↗
PubMed1978

Mitotic recombination in the heterochromatin of the sex chromosomes of Drosophila melanogaster.

The frequency of spontaneous and X-ray-induced mitotic recombination involving the Y chromosome has been studied in individuals with a marked Y chromosome arm and different XY compound chromosomes. The genotypes used include X chromosomes with different amounts of X heterochromatin and either or both arms of the Y chromosome attached to either side of the centromere. Individuals with two Y chromosomes have also been studied. The results show that the bulk of mitotic recombination takes place between homologous regions.

Animals↗
PubMed1972

Developmental analysis of the wing disc in the mutant engrailed of Drosophila melanogaster.

The engrailed (en) mutation leads to the transformation of the posterior structures of the dorsal mesothoracic disc into those characteristic of the anterior region of the same disc. Similar posterior-anterior duplications have been detected in dorsal as well as ventral structures of all the thoracic segments. -Genetic combinations of en with other pattern mutants have shown their synergistic effect on the posterior wing pattern.-A clonal analysis of the en wing disc shows that en affects its development in a characteristic way. The genetic change, by induced mitotic recombination, of en(+) into en cells is followed by the corresponding transformation, except when it takes place some cell divisions prior to differentiation.-The en posterior wing disc cells show positive affinities with normal anterior wing disc cells in aggregates.-The mode of action of the en(+) locus controlling wing disc development is discussed.

Age Factors↗