In our previous Genome-wise Association Study we found that Cystic Fibrosis Transmem- brane Conductance Regulator gene (CFTR) is a candidate gene for sperm motility in fresh semen of Holstein-Friesian bulls. Since in cows thawed semen is commonly used for the artificial insem- ination (AI) we have decided to find out whether functional polymorphism within CFTR gene coding sequence is associated with selected parameters of thawed sperm, including their motility evaluated by computer-assisted sperm analysis (CASA), the activity of three antioxidant enzymes: glutathione peroxidase (GPx) catalase (CAT), superoxide dismutase (SOD), ATP con- tent and integrity of sperm membranes. One hundred twenty Holstein Friesian bulls kept in uni- form environmental conditions (one AI company) were included in the study. Significant associ- ations between genotypes of missense mutation within exon 11 of the CFTR gene (Met468Leu) and the activity of antioxidant enzymes and sperm mitochondrial function were revealed. No effect of CFTR genotypes on sperm motility was observed. Significant differences in CAT and SOD activity were found between AA and TT homozygous individuals. Bulls with TT genotype had the lowest activity of both antioxidant enzymes. The same bulls also showed the lowest num- ber of sperm with active mitochondria. Our results demonstrate that missense mutation Met468Leu within CFTR gene is associated with antioxidant enzyme activity and mitochondrial function of bovine thawed sperm without affecting their motility.
Leaf scald, caused by the necrotrophic fungus Monographella albescens, is one of the main threats to rice (Oryza sativa L.) around the world. This disease decreases yields in rice by up to 30% because of dead leaf tissue, damaged seeds, and sterile flowers. Currently, there is limited knowledge about the molecular mechanisms involved in rice plant resistance against this pathogen. For this purpose, six commercial cultivars of rice were primarily screened for M. albescens infection and development. Dasht and Salari were found to be the most resistant and susceptible to M. albescens infection, respectively. The plants were kept in a greenhouse at 29 ± 2°C during the day and 26 ± 2°C at night with a relative air humidity of 85 ± 5%. Forty-five days after sowing, the plants with three biological replications were inoculated by transferring a PDA disc (0.3 cm2) containing M. albescens mycelia to the middle third of the 7th, 8th, and 9th completely open leaves. The leaves were collected 24, 48, 72, 96 and 120 hai. Leaf samples were also collected from the non-inoculated plants (0 h) to serve as controls. Real-time quantitative PCR (RT-qPCR) showed rapid induction and significant accumulation of jasmonic acid (JA) and ethylene (ET) responsive genes such as lipoxygenase (LOX), allene oxide synthase 2 (Aos2), jasmonic acid carboxyl methyltransferase 1 (JMT1) and ACC synthase 1 (ACS1) in the resistant Dasht cultivar after infection with M. albescens. Furthermore, the transcripts of salicylic acid (SA) responsive phenyl alanine ammonia lyase 1 (PAL1) and nonexpressor of pathogenesis-related genes 1 (NPR1) genes were induced in the incompatible interaction. The activities of the defense enzymes superoxide dismutase (SOD), peroxidase (POX) and glutathione reductase (GR) increased strongly in Dasht in response to M. albescens infection. In addition, there was an increase in the H2O2 levels in the leaves of the Dasht cultivar during the infectious period of M. albescens associated with the enhancement of catalase (CAT) activity as well as higher levels of malondialdehyde (MDA). This is the first study on the interaction between rice and M. albescens at the molecular level. It can contribute to understanding how rice responds to pathogen infection, as well as assist with future research plans of molecular breeding regarding the tolerance to leaf scald disease.