Biomaterial Database

Recombination and hydroxyurea inhibition of DNA synthesis in yeast meiosis. 1976

G Simchen, and D Idar, and Y Kassir

Hydroxyurea (HU) inhibits the premeiotic DNA replication and the meiotic events that followed, namely readiness, recombination commitment, haploidisation, sporulation commitment and ascus formation. Short incubations with HU (2-4 hrs) during the premeiotic replication (i.e. starting between 3 and 6.5 hrs in sporulation medium) allow the resumption of the replication at a normal rate following the removal of the drug. The other meiotic events are similarly delayed by the approximate length of the treatment. In these experiments, intragenic recombination in ade2 reached a higher level than in the controls (x 1.3-2.0 in one pair of heteroalleles and x 3.0-4.0 in another pair). The recombination response to short HU treatments was not observed for a pair of heteroalleles in ade2 that normally shows a high level of meiotic recombination (750 per 10(6) cells), nor was the response observed in a pair of heteroalleles in lys2. HU treatments have almost no effect on sporulating cells from 8 hrs onwards. At 7-7.5 hrs the meiotic cells are very sensitive to the drug and even short treatments cause cell death and massive DNA degradation.

UI	MeSH Term	Description	Entries
D008540	Meiosis	A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.	M Phase, Meiotic,Meiotic M Phase,M Phases, Meiotic,Meioses,Meiotic M Phases,Phase, Meiotic M,Phases, Meiotic M
D011995	Recombination, Genetic	Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.	Genetic Recombination,Recombination,Genetic Recombinations,Recombinations,Recombinations, Genetic
D004171	Diploidy	The chromosomal constitution of cells, in which each type of CHROMOSOME is represented twice. Symbol: 2N or 2X.	Diploid,Diploid Cell,Cell, Diploid,Cells, Diploid,Diploid Cells,Diploidies,Diploids
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
D005787	Gene Frequency	The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.	Allele Frequency,Genetic Equilibrium,Equilibrium, Genetic,Allele Frequencies,Frequencies, Allele,Frequencies, Gene,Frequency, Allele,Frequency, Gene,Gene Frequencies
D006918	Hydroxyurea	An antineoplastic agent that inhibits DNA synthesis through the inhibition of ribonucleoside diphosphate reductase.	Hydroxycarbamid,Hydrea,Oncocarbide
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013172	Spores, Fungal	Reproductive bodies produced by fungi.	Conidia,Fungal Spores,Conidium,Fungal Spore,Spore, Fungal
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor