Biomaterial Database

Induction of a Ca2+, Mg2+-dependent endonuclease activity during the early stages of murine erythroleukemic cell differentiation. 1984

G McMahon, and J L Alsina, and S B Levy

A Ca2+, Mg2+-dependent endonuclease activity was detected in erythroleukemic cells undergoing differentiation in vitro in response to induction by dimethyl sulfoxide (Me2SO) or hexamethylene-bis-acetamide (HMBA). The endonuclease activity was demonstrated in isolated nuclei within 6 hr after the addition of inducer, reached maximum levels between 24 and 48 hr, and returned to control levels within 72 hr. The activity caused single strand breaks in high molecular weight native DNA, which could be labeled at exposed 3'-OH termini with Escherichia coli DNA polymerase I and radiolabeled nucleotides. Alkaline elution studies revealed DNA fragmentation that appeared coincident with the presence of the endonuclease activity. The detection and levels of single strand DNA breakage correlated with induction of terminal differentiation by Me2SO or HMBA. Induction of the endonuclease activity was reversible: depletion of Me2SO from the growth medium after treatment for 6 and 18 hr led to a rapid decrease in the level of activity. Removal of the inducer prevented terminal differentiation, a finding that strongly suggests the endonuclease activity is present during the precommitment phase of differentiation. DNA fragmentation was not observed in cells incubated with hemin, which has been shown previously to increase the cytoplasmic level of globin mRNA without causing commitment to terminal maturation. Me2SO did not induce the endonuclease activity or DNA fragmentation in an uninducible Friend cell line.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007942	Leukemia, Experimental	Leukemia induced experimentally in animals by exposure to leukemogenic agents, such as VIRUSES; RADIATION; or by TRANSPLANTATION of leukemic tissues.	Experimental Leukemia,Experimental Leukemias,Leukemia Model, Animal,Leukemias, Experimental,Animal Leukemia Model,Animal Leukemia Models,Leukemia Models, Animal
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D004121	Dimethyl Sulfoxide	A highly polar organic liquid, that is used widely as a chemical solvent. Because of its ability to penetrate biological membranes, it is used as a vehicle for topical application of pharmaceuticals. It is also used to protect tissue during CRYOPRESERVATION. Dimethyl sulfoxide shows a range of pharmacological activity including analgesia and anti-inflammation.	DMSO,Dimethyl Sulphoxide,Dimethylsulfoxide,Dimethylsulphinyl,Dimethylsulphoxide,Dimexide,Rheumabene,Rimso,Rimso 100,Rimso-50,Sclerosol,Sulfinylbis(methane),Rimso 50,Rimso50,Sulfoxide, Dimethyl,Sulphoxide, Dimethyl
D004273	DNA, Neoplasm	DNA present in neoplastic tissue.	Neoplasm DNA
D004706	Endodeoxyribonucleases	A group of enzymes catalyzing the endonucleolytic cleavage of DNA. They include members of EC 3.1.21.-, EC 3.1.22.-, EC 3.1.23.- (DNA RESTRICTION ENZYMES), EC 3.1.24.- (DNA RESTRICTION ENZYMES), and EC 3.1.25.-.
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
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