Biomaterial Database

Cell cycle dependence of mitotic delay in X-irradiated normal and ataxia-telangiectasia fibroblasts. 1982

D Scott, and F Zampetti-Bosseler

The delay in progression of X-irradiated cells through the cell cycle, which is more pronounced in normal (N) than in A-T fibroblasts, is greatest for cells in G2 at the time of irradiation. The greater effect of radiation on the initiation of DNA synthesis in N than in A-T cells is reflected in the shape of the percent labelled mitosis curves after 3H-thymidine treatment. The duration of the S phase in unirradiated A-T cells is greater than in N cells. Any explanation of the underlying defect in A-T must account not only for the reduced radiosensitivity of DNA synthesis but for the lesser delay in G2. Our data support the hypothesis that DNA is the principal target for radiation-induced G2 delay.

UI	MeSH Term	Description	Entries
D008938	Mitosis	A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.	M Phase, Mitotic,Mitotic M Phase,M Phases, Mitotic,Mitoses,Mitotic M Phases,Phase, Mitotic M,Phases, Mitotic M
D008940	Mitotic Index	An expression of the number of mitoses found in a stated number of cells.	Index, Mitotic,Indices, Mitotic,Mitotic Indices
D002453	Cell Cycle	The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.	Cell Division Cycle,Cell Cycles,Cell Division Cycles,Cycle, Cell,Cycle, Cell Division,Cycles, Cell,Cycles, Cell Division,Division Cycle, Cell,Division Cycles, Cell
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001260	Ataxia Telangiectasia	An autosomal recessive inherited disorder characterized by choreoathetosis beginning in childhood, progressive CEREBELLAR ATAXIA; TELANGIECTASIS of CONJUNCTIVA and SKIN; DYSARTHRIA; B- and T-cell immunodeficiency, and RADIOSENSITIVITY to IONIZING RADIATION. Affected individuals are prone to recurrent sinobronchopulmonary infections, lymphoreticular neoplasms, and other malignancies. Serum ALPHA-FETOPROTEINS are usually elevated. (Menkes, Textbook of Child Neurology, 5th ed, p688) The gene for this disorder (ATM) encodes a cell cycle checkpoint protein kinase and has been mapped to chromosome 11 (11q22-q23).	Louis-Bar Syndrome,Ataxia Telangiectasia Syndrome,Ataxia-Telangiectasia,Telangiectasia, Cerebello-Oculocutaneous,Louis Bar Syndrome,Syndrome, Ataxia Telangiectasia,Syndrome, Louis-Bar
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor