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B Z Shilo

Publications and source records attributed to B Z Shilo.

60 records · Page 4Linked to original sources

Drosophila melanogaster DNA clones homologous to vertebrate oncogenes: evidence for a common ancestor to the src and abl cellular genes.

We have isolated phage clones containing the D. melanogaster sequence homologous to the v-abl oncogene, and two types of phage clones containing sequences homologous to the v-src probe. The D. melanogaster abl clone (lambda Dabl1) and one of the src clones (lambda Dsrc1) hybridize with both v-abl and v-src probes, and both map in situ to the same chromosomal position, 73B, on chromosome arm 3L. The second D. melanogaster src clone (lambda Dsrc2) does not react with the v-abl probe and hybridizes in situ to chromosomal position 64B. The hybridization pattern suggests that the src and abl cellular oncogenes have evolved from a common prototype sequence. The homologous sequences in D. melanogaster exhibit hybridization to regions in the vertebrate v-abl and v-src that are important for kinase activity and transforming potential of the viral gene products.

Animals↗

Three different human tumor cell lines contain different oncogenes.

We have obtained foci of transformed mouse cells after transfection of human DNA from colon and bladder carcinoma cell lines and a promyelocytic leukemia cell line. These foci can be shown to contain a large number of human DNA sequences by use of highly repetitive human DNA sequence probes. Cell DNA from primary foci can be used in a subsequent cycle of transfection resulting in secondary foci that contain relatively little human DNA. Secondary foci appear to contain only the human sequences proximal to those responsible for the transformed phenotype. A set of characteristic DNA restriction fragments is found in common among secondary foci derived from each tumor cell line DNA. Comparison of the common DNA fragments found in secondary foci derived from three different human tumor cell lines indicates that these three cell lines contain three different transforming genes.

Animals↗

DNA sequences homologous to vertebrate oncogenes are conserved in Drosophila melanogaster.

Sequences homologous to the oncogene sequences of acute RNA tumor viruses have been shown to be highly conserved within vertebrates. In the present work, eight different oncogene DNA sequences have been used as probes to search for homologous sequences in the DNA of organisms of other phyla. Five of these probes hybridized to the DNA of Drosophila melanogaster. Abelson leukemia virus probe detected a single homologous DNA fragment in Drosophila DNA. In contrast, probes prepared from the genomes of Harvey, avian, and feline sarcoma viruses and avian myelocytomatosis virus hybridized with multiple homologous sequences in Drosophila DNA. The identification of sequences homologous to vertebrate oncogenes in invertebrates demonstrates both a high degree of conservation of these genes and a wide distribution among divergent species. It seems likely that sequences homologous to vertebrate oncogenes play a crucial role in metazoan metabolism.

Abelson murine leukemia virus↗

Passage of phenotypes of chemically transformed cells via transfection of DNA and chromatin.

DNA was prepared from 15 different mouse and rat cell lines transformed by chemical carcinogens in vitro and in vivo. These DNAs were applied to NIH3T3 mouse fibroblast cultures by using the calcium phosphate transfection technique. DNAs of five donor lines were able to induce foci on the recipient monolayers. Ten other donor DNAs yielded few or no foci. DNAs from control, nontransformed parental cell lines induced few or no foci. Chromosomes were transfected from one donor whose naked DNA was unable to induce foci, and morphologic transformation of recipients was observed. These experiments prove that in five of these cell lines the chemically induced phenotype is encoded in DNA, and the sequences specifying the transformed phenotype behave as a dominant allele in the NIH3T3 recipient cells. The sequences encoding the transformation are likely found on a single fragment of DNA.

Alleles↗

Developmental control by the Drosophila EGF receptor homolog DER.

The identification of receptor tyrosine kinases in Drosophila has provided an opportunity to study the requirement for these proteins during the development of a multicellular organism. Genetic analysis of the function of the Drosophila epidermal growth factor (EGF) receptor homolog (DER) has revealed an extremely diverse set of roles for this protein throughout the life cycle of the organism, for example in eye development and in the establishment of dorsoventral polarity in the oocyte. We discuss the possible basis for the pleiotropic activity of DER, and the similarities and differences in the function of the homologous proteins in other invertebrates and vertebrates.

Animals↗