Biomaterial Database

DNase-sensitive chromatin structure near a chromosomal origin of bidirectional replication of the avian alpha-globin locus. 1993

S Berberich, and M Leffak

Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435.

We used an in vitro nuclear run-off replication assay to analyze the direction of replication in a 13-kb region 5' to the avian alpha-globin genes. Previous work from this laboratory suggested that the alpha-globin genes of 5-day chick red blood cells and avian MSB cells replicate in vivo in the transcriptional direction, possibly from a chromosomal origin near the alpha pi-globin gene. Here we extend those studies by showing that replication forks move divergently from an 8-kb region of alpha-globin 5'-flanking DNA. One potential zone for the initiation of bidirectional replication was located approximately 2.5 kb 5' to the alpha pi-globin gene in both of these cell types. Additionally, a barrier to replication fork movement, which may be located in a second origin zone, was found approximately 5 kb farther upstream. Both in 5-day RBCs, where the alpha-globin genes are expressed, and in MSB cells where they are not expressed, DNase I hypersensitive structures were found approximately 5 kb 5' to the alpha pi-globin gene, in the putative replication initiation domain. Another DNase I hypersensitive site was confirmed to exist in 5-day RBC nuclei upstream of the transcribed alpha pi-globin gene. These results suggest that replication of the alpha-globin genes initiates in the nearby 5'-flanking DNA of this locus in a region marked by distinct chromatin structures.

UI	MeSH Term	Description	Entries
D012045	Regulatory Sequences, Nucleic Acid	Nucleic acid sequences involved in regulating the expression of genes.	Nucleic Acid Regulatory Sequences,Regulatory Regions, Nucleic Acid (Genetics),Region, Regulatory,Regions, Regulatory,Regulator Regions, Nucleic Acid,Regulatory Region,Regulatory Regions
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D002843	Chromatin	The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.	Chromatins
D003851	Deoxyribonucleases	Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.	DNAase,DNase,Deoxyribonuclease,Desoxyribonuclease,Desoxyribonucleases,Nucleases, DNA,Acid DNase,Alkaline DNase,DNA Nucleases,DNase, Acid,DNase, Alkaline
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D005914	Globins	A superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.	Globin
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
D015183	Restriction Mapping	Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.	Endonuclease Mapping, Restriction,Enzyme Mapping, Restriction,Site Mapping, Restriction,Analysis, Restriction Enzyme,Enzyme Analysis, Restriction,Restriction Enzyme Analysis,Analyses, Restriction Enzyme,Endonuclease Mappings, Restriction,Enzyme Analyses, Restriction,Enzyme Mappings, Restriction,Mapping, Restriction,Mapping, Restriction Endonuclease,Mapping, Restriction Enzyme,Mapping, Restriction Site,Mappings, Restriction,Mappings, Restriction Endonuclease,Mappings, Restriction Enzyme,Mappings, Restriction Site,Restriction Endonuclease Mapping,Restriction Endonuclease Mappings,Restriction Enzyme Analyses,Restriction Enzyme Mapping,Restriction Enzyme Mappings,Restriction Mappings,Restriction Site Mapping,Restriction Site Mappings,Site Mappings, Restriction