Folliculogenesis-related genes are differently expressed in secondary and tertiary ovarian follicles

Summary The relative mRNA abundance of 10 genes associated with folliculogenesis was compared between late preantral (secondary) and early antral (tertiary) ovarian follicles in goats. In total, 100 follicles in each category were mechanically isolated. The relative transcript abundance of the mRNAs were determined by qPCR. Data were analyzed using unpaired Student’s t-test. Of the 10 tested genes, ABLIM mRNA was not detected in either follicle category, six genes (SLIT3, TYMS, GTPBP1, AKR1C4, PIK3R6, and MAOB) were upregulated in secondary follicles compared with tertiary follicles, and three genes (ARHGEF12, CLEC6A, and CYTL1) showed similar mRNA abundances in both secondary and tertiary follicles. In conclusion, SLIT3, GTPBP1, AKR1C4, and PIK3R6 mRNA abundance was upregulated in secondary follicles (preantral phase) compared with in tertiary follicles (antral phase) in goats.

Analysis of Cadmium Root Retention for Two Contrasting Rice Accessions Suggests an Important Role for OsHMA2

Two rice accessions, Capataz and Beirao, contrasting for cadmium (Cd) tolerance and root retention, were exposed to a broad range of Cd concentrations (0.01, 0.1, and 1 μM) and analyzed for their potential capacity to chelate, compartmentalize, and translocate Cd to gain information about the relative contribution of these processes in determining the different pathways of Cd distribution along the plants. In Capataz, Cd root retention increased with the external Cd concentration, while in Beirao it resulted independent of Cd availability and significantly higher than in Capataz at the lowest Cd concentrations analyzed. Analysis of thiol accumulation in the roots revealed that the different amounts of these compounds in Capataz and Beirao, as well as the expression levels of genes involved in phytochelatin biosynthesis and direct Cd sequestration into the vacuoles of the root cells, were not related to the capacity of the accessions to trap the metal into the roots. Interestingly, the relative transcript abundance of OsHMA2, a gene controlling root-to-shoot Cd/Zn translocation, was not influenced by Cd exposure in Capataz and progressively increased in Beirao with the external Cd concentration, suggesting that activity of the OsHMA2 transporter may differentially limit root-to-shoot Cd/Zn translocation in Capataz and Beirao.

Nano-ZnO-Induced Drought Tolerance Is Associated with Melatonin Synthesis and Metabolism in Maize

The applications of ZnO nanoparticles in agriculture have largely contributed to crop growth regulation, quality enhancement, and induction of stress tolerance, while the underlying mechanisms remain elusive. Herein, the involvement of melatonin synthesis and metabolism in the process of nano-ZnO induced drought tolerance was investigated in maize. Drought stress resulted in the changes of subcellular ultrastructure, the accumulation of malondialdehyde and osmolytes in leaf. The nano-ZnO (100 mg L−1) application promoted the melatonin synthesis and activated the antioxidant enzyme system, which alleviated drought-induced damage to mitochondria and chloroplast. These changes were associated with upregulation of the relative transcript abundance of Fe/Mn SOD, Cu/Zn SOD, APX, CAT, TDC, SNAT, COMT, and ASMT induced by nano-ZnO application. It was suggested that modifications in endogenous melatonin synthesis were involved in the nano-ZnO induced drought tolerance in maize.

Effects of vitrification on the expression of pluripotency, apoptotic and stress genes in in vitro-produced porcine blastocysts

The aims of the present study were to: (1) evaluate the effect of vitrification and warming on quality parameters and expression levels of pluripotency, apoptotic and stress genes in in vitro-produced (IVP) porcine blastocysts; and (ii) determine the correlation between these parameters. To this end, total cell number, DNA fragmentation, peroxide levels and the relative transcript abundance of BCL-2 associated X protein (BAX), BCL2-like 1 (BCL2L1), heat shock protein 70 (HSPA1A), POU class 5 homeobox 1 (POU5F1), superoxide dismutase 1 (SOD1) and superoxide dismutase 2 (SOD2) were analysed in fresh and vitrified IVP blastocysts. The results suggest that vitrification procedures have no effect on total cell number and gene expression of BAX, BCL2L1, SOD1 and SOD2 or the BAX : BCL2L1 ratio. Nevertheless, a significant increase in DNA fragmentation (2.9 ± 0.4% vs 11.9 ± 2.0%) and peroxide levels (80.4 ± 2.6 vs 97.2 ± 3.1) were seen in vitrified compared with Day 7 fresh blastocysts. In addition, after blastocyst vitrification, relative transcript abundance was downregulated for POU5F1 and upregulated for HSPA1A. Finally, there was a significant correlation of POU5F1 and HSPA1A with DNA fragmentation (POU5F1, r = –0.561; HSPA1A, r = 0.604) and peroxide levels (POU5F1, r = –0.590; HSPA1A, r = 0.621). In conclusion, under the conditions of the present study, vitrification and warming of IVP porcine blastocysts resulted in altered expression of POU5F1 and HSPA1A, but had no effect on BAX, BCL2L1, SOD1 and SOD2 expression.

299 EFFECT OF ESTRADIOL-17β AND FOLLICLE STIMULATING HORMONE ON THE IN VITRO MATURATION OF PORCINE OOCYTES DERIVED FROM SMALL FOLLICLES

In porcine cumulus-oocyte complexes (COC) from middle follicles (MF: 3–6 mm in diameter), FSH is known to induce the resumption of meiosis and accompanied by transactivate of the EGF receptor and activation of MAPK3/1 in the cumulus cells. The aim of the current study was to examine the effect of oestradiol-17β (E2: 0.1 μg mL–1) or FSH on in vitro maturation (IVM) of porcine oocytes derived from small follicles (SF: 1–2 mm in diameter). The COC were aspirated from MF of porcine ovaries obtained at slaughterhouse and cultured for IVM in mPOM (with 1 mM dibutyryl cAMP, 10 IU mL–1 of eCG, and 10 IU mL–1 of hCG for 20 h and then without those for 24 h in an atmosphere of 5% CO2 in air at 39°C) after washing 3 times. The COC from SF, which were aspirated at the same time with COC from MF, were precultured in the absence or presence of E2 or E2 plus FSH for 6 h before IVM culture. After the culture, oocytes were denuded from cumulus cells with 0.1% (vol/vol) hyaluronidase and the meiotic stage was observed. Relative transcript abundance of FSH and EGF receptors of CC was also examined by real-time RT–PCR just after preincubation for 6 h. Statistical analysis of data from 3 to 5 replicates was analysed by ANOVA and Tukey's multiple comparison tests. Maturation rate of oocytes from SF (40.6 ± 3.1%) was significantly lower than that of oocytes from MF controls (78.8 ± 2.8%, P < 0.01). Preincubation in the presence of E2 alone and E2 plus 0.005 IU of FSH significantly increases the maturation rate of oocytes from SF (56.8 ± 1.5 and 55.7 ± 3.1%, respectively, P < 0.01), although the rate was still lower than MF controls. However, in the presence of E2 plus a higher concentration of FSH (0.05 and 0.5 IU), oocyte maturation rate was similar (36.3 ± 2.4 and 33.7 ± 1.9%, respectively) to SF controls and lower than those of E2 alone and E2 plus 0.005 IU of FSH groups. Relative transcript abundance of FSH receptor of CC increased (P < 0.01) during preincubation in the presence of E2, but decreased in the presence of 0.05 IU of FSH. There were no significant differences in the transcript abundance of EGF receptors among treatments during preincubation (P = 0.09). In conclusion, preincubation of COC from SF in the presence of E2 alone and E2 plus 0.005 IU of FSH improves the maturation rate of the oocytes, whereas the presence of FSH more than 0.05 IU mL–1 concealed the positive effect. These effects may be yielded by change in the relative transcript abundance of FSH receptor of COC through the treatments.