RAD51 maintains chromosome integrity and mitochondrial distribution during porcine oocyte maturation <i>in vitro</i>

Abstract

DNA repair protein RAD51 homolog 1 (RAD51) plays a central role in homologous recombination (HR) repair of DNA breaks. HR depends on the formation of a RAD51 recombinase filament that facilitates strand invasion. However, the role of RAD51 during porcine oocyte maturation is unknown. The objective of this study was to investigate the expression and function of RAD51 during porcine oocyte maturation in vitro. RAD51 was mainly localized to the nucleus at the germinal vesicle (GV) stage, and was widely distributed in the cytoplasm between the GV breakdown (GVBD) and metaphase II stage. DNA damage induced by etoposide was accompanied by the formation of RAD51 foci that were colocalized with γH2AX. Inhibition of RAD51 increased DNA damage and induced metaphase I arrest along with spindle defects, chromosomal misalignment, and abnormal spindle assembly checkpoint (SAC) activity. Inhibition of RAD51 also increased ROS levels and led to an abnormal mitochondrial distribution. Our results indicate that RAD51 plays a critical role in maintaining chromosome integrity and mitochondrial activity during porcine oocyte maturation.

Inhibition of DNA repair protein RAD51 affects porcine preimplantation embryo development

“…Thus, we speculate that the DNA repair protein, RAD51, mainly functions in the four-cell stage. Previously, deletion or inhibition of RAD51-induced DNA damage in oocyte meiosis (Kim et al 2016, Jin & Kim 2017. Consistently, we observed similar results in porcine PA embryos.…”

“…Immunostaining was performed as previously described (Jin & Kim 2017). The antibodies used were rabbit anti-RAD51 (sc-8349, 1:100; Santa Cruz Biotechnology), mouse anti-γH2AX (ab26350, 1:100; Abcam), rabbit anti-ATM (pS1981, 1:100; Cell Signaling Technology), goat anti-OCT4 (sc-8628, 1:100; Santa Cruz), rabbit anti-p53 (sc6243, 1:100; Santa Cruz), rabbit anti-SOX2 (sc-17320, 1:100; Santa Cruz), and mouse anti-p21 (P1484, 1:1000; Sigma-Aldrich).…”

“…Moreover, depletion of RAD51 in mouse oocytes caused a decrease in ATP production and mitochondrial defect-activated autophagy (Kim et al 2016). We recently reported (Jin & Kim 2017) that inhibition of RAD51 in porcine oocytes-induced metaphase I arrest along with spindle defects, chromosomal misalignment and abnormal mitochondrial distribution, indicating that RAD51 functions to safeguard mitochondrial integrity during meiotic maturation.…”

hCINAP regulates the DNA-damage response and mediates the resistance of acute myelocytic leukemia cells to therapy

“…RAD51 has a central role in the HR pathway. After a DSB occurs, RAD51 promotes invasion of ssDNA into undamaged homologous dsDNA 30 . We further assessed the role of hCINAP in the end resection process by examining its influence on IR-induced RAD51 protein recruitment.…”

Synthesis, Characterization, and Antibacterial Activity of Ag2O-Loaded Polyethylene Terephthalate Fabric via Ultrasonic Method

“…The fabric discs containing Ag2O nanomaterial were placed on each Petri dish and a piece of uncoated fabric was used as a control in each set of tests. The Petri dishes were incubated at 35 °C for 24 h, digital images of the plates were captured, and the inhibition zone was calculated using an image processing software (image J.140, University of Wisconsin, Madison, WI, USA) [20,30]; each test was repeated three times and the average results were reported.…”