* Meiosis progression and donor age affect expression profile of DNA repair genes in bovine oocytes.
- Several genetic and physiological factors increase the risk of DNA damage in mammalian oocytes. Two critical events are: (i) meiosis progression, from maturation to fertilization, due to extensive chromatin remodelling during genome decondensation; and (ii) aging, which is associated with a progressive oxidative stress. In this work, we studied the transcriptional patterns of three genes, RAD51, APEX-1 and MLH1, involved in DNA repair mechanisms. The analyses were performed by real-time quantitative PCR (RT-qPCR) in immature and in vitro matured oocytes collected from 17 ± 3-month-old heifers and 94 ± 20-month-old cows. Batches of 30-50 oocytes for each group (three replicates) were collected from ovarian follicles of slaughtered animals. The oocytes were freed from cumulus cells at the time of follicle removal, or after in vitro maturation (IVM) carried out in M199 supplemented with 10% fetal calf serum, 10 IU luteinising hormone (LH)/ml, 0.1 IU follicle-stimulating hormone (FSH)/ml and 1 μg 17β-oestradiol/ml. Total RNA was extracted by Trizol method. The expression of bovine GAPDH gene was used as the internal standard, while primers for bovine RAD51, APEX-1 and MLH1 genes were designed from DNA sequences retrieved from GenBank. Results obtained indicate a clear up-regulation of RAD51, APEX-1 and MLH1 genes after IVM, ranging between two- and four-fold compared with germinal vesicle (GV) oocytes. However, only RAD51 showed a significant transcript increase between the immature oocytes collected from young or old individuals. This finding highlights RAD51 as a candidate gene marker for discriminating bovine immature oocytes in relation to the donor age.
=>1.損害の恐れ, 危険, 冒険, リスク, 2.危険にさらす, 3.敢えてする, 被保険者, 被保険物, 危険にさらす,
賭けてみる
Overview of noun risk
The noun risk has 4 senses (first 2 from tagged texts)
1. (4) hazard, jeopardy, peril, risk, endangerment -- (a source of danger; a possibility of
incurring loss or misfortune; "drinking alcohol is a health hazard")
2. (2) risk, peril, danger -- (a venture undertaken without regard to possible loss or injury; "he
saw the rewards but not the risks of crime"; "there was a danger he would do the wrong thing")
3. risk, risk of infection -- (the probability of becoming infected given that exposure to an
infectious agent has occurred)
4. risk, risk of exposure -- (the probability of being exposed to an infectious agent)
Overview of verb risk
The verb risk has 2 senses (first 2 from tagged texts)
1. (8) risk, put on the line, lay on the line -- (expose to a chance of loss or damage; "We risked
losing a lot of money in this venture"; "Why risk your life?"; "She laid her job on the line when
she told the boss that he was wrong")
2. (2) gamble, chance, risk, hazard, take chances, adventure, run a risk, take a chance -- (take a
risk in the hope of a favorable outcome; "When you buy these stocks you are gambling")
--- WordNet end ---