Biomaterial Database

Differences between the endogenous and exogenous DNA sequences of Rous-associated virus-O. 1979

E H Humphries, and C Glover, and R A Weiss, and J R Arrand

DNA sequences related to the endogenous retrovirus of chickens, Rous-associated virus-O (RAV-O), have been examined using site-specific DNA endonuclease analysis of cellular DNA derived from line 15 and line 100 chickens. Individual embryos from both inbred lines were used as a source of embryonic fibroblasts from which cellular DNA was isolated. Analysis of DNA containing either endogenous RAV-O sequences alone or both endogenous and exogenous RAV-O sequences produced identical patterns of RAV-O-specific DNA fragments after digestion with the endonucleases Eco RI, Hind III, BgI II, Bam HI or Xho I. Similar analysis with endonucleases Hinc II or Hha I, however, produced several RAV-O-specific DNA fragments which were derived from cellular DNA containing both endogenous and exogenous RAV-O sequences but not from cellular DNA containing only endogenous sequences. Although some differences exist between the DNA fragments specific for the endogenous viral sequences of line 15 and line 100 cellular DNA, the DNA fragments specific for the exogenous viral sequences were identical between the two inbred lines. Cleavage of an unintegrated linear RAV-O DNA molecule with Hinc II or Hha I produced DNA fragments identical to those specific for the exogenously acquired RAV-O provirus. This suggests that these characteristic fragments contain no cellular DNA. The potential DNA junction fragments containing both viral and cellular DNA, identified after analysis of DNA that contains both endogenous and exogenous viral sequences, were identical to those observed after analysis of DNA containing only endogenous viral sequences. These results support the following conclusions. First, exogenous proviral sequences are integrated into chicken cell DNA following an interaction between viral and cellular DNA that is specific with respect to the virus and nonspecific with respect to the cell. Second, both the free linear RAV-O DNA intermediate and the newly integrated exogenous provirus contain specific endonuclease sites that are not found in endogenous RAV-O DNA sequences. These results suggest that the formation of the exogenous DNA provirus involves specific alteration of the endogenous viral DNA sequences before reinsertion of the sequences as the exogenous RAV-O DNA provirus. It is possible that newly integrated exogenous RAV-O sequences are characterized by specific differences in the pattern of base methylation and a limited sequence arrangement.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D002471	Cell Transformation, Neoplastic	Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.	Neoplastic Transformation, Cell,Neoplastic Cell Transformation,Transformation, Neoplastic Cell,Tumorigenic Transformation,Cell Neoplastic Transformation,Cell Neoplastic Transformations,Cell Transformations, Neoplastic,Neoplastic Cell Transformations,Neoplastic Transformations, Cell,Transformation, Cell Neoplastic,Transformation, Tumorigenic,Transformations, Cell Neoplastic,Transformations, Neoplastic Cell,Transformations, Tumorigenic,Tumorigenic Transformations
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D004262	DNA Restriction Enzymes	Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.	Restriction Endonucleases,DNA Restriction Enzyme,Restriction Endonuclease,Endonuclease, Restriction,Endonucleases, Restriction,Enzymes, DNA Restriction,Restriction Enzyme, DNA,Restriction Enzymes, DNA
D004279	DNA, Viral	Deoxyribonucleic acid that makes up the genetic material of viruses.	Viral DNA
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001358	Avian Sarcoma Viruses	Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.	Avian Sarcoma Virus B77,Chicken Sarcoma Virus B77,Chicken Tumor 1 Virus,Fujinami sarcoma virus,Sarcoma Viruses, Avian,Avian Sarcoma Virus,Fujinami sarcoma viruses,Sarcoma Virus, Avian,Virus, Avian Sarcoma,Viruses, Avian Sarcoma,sarcoma virus, Fujinami,virus, Fujinami sarcoma,viruses, Fujinami sarcoma