KISS1 Gene Expression in the Developing Brain of Female Pigs in Pre- and Peripubertal Periods

Puberty is associated with an increase in gonadotropin secretion as a result of an increase in gonadotropin-releasing hormone (GnRH) secretion. Kisspeptin is considered to play a key role in puberty onset in many mammalian species, including rodents, ruminants and primates. The present study aimed to determine if changes in hypothalamic expression of the KISS1 gene, encoding kisspeptin, are associated with the onset of puberty in pigs. The animals (n=4 in each group) were perfused with 4% paraformaldehyde at 0, 1, 2, 3 and 4 months old, as prepubertal stages, and at 5 months old, as the peripubertal stage, following each blood sampling. KISS1 gene expressions in coronal sections of brains were visualized by in situ hybridization. Plasma luteinizing hormone (LH) was measured by radioimmunoassay. KISS1 mRNA signals were observed in the arcuate nucleus (ARC) at all ages examined without any significant difference in the number of KISS1-expressing cells, indicating that the KISS1 gene is constantly expressed in the ARC throughout pubertal development in pigs. The plasma LH concentration was the highest in 0-month-old piglets and significantly decreased in the 1- and 2 month-old groups (P<0.05), suggesting a developing negative feedback mechanism affecting gonadotropin release during the prepubertal period. Considering the potent stimulating effect of kisspeptin on gonadotropin release in prepubertal pigs, kisspeptin secretion rather than kisspeptin synthesis may be responsible for the onset of puberty in pigs.     

The evaluation of secretion volume and immunoglobulin A and G concentrations in sow colostrum from anterior to posterior teats

Among domestic animals, teat order is only observed in the pig. In order to achieve the healthy growth and weaning of piglets, it is important to elucidate if volume of colostrum secretion and immunoglobulin A (IgA) and IgG concentrations differ among the teats of a sow. Nine sows were used to evaluate the difference in colostrum secretion volume (CSV) and four of these sows were assessed for IgA and IgG concentrations from each teat. Samples were collected five times during 21 h following parturition. Teats were assigned anatomical locations of teat (1 to 7) from anterior to posterior. The CSV of anterior (locations 1 and 2) and middle teats (locations 3–5) was significantly higher than those of posterior teats (locations 6 and 7) throughout the experiment except for 18 h post‐parturition (P < 0.05). The CSV of the teats at location 1 was significantly higher at most collection times than those at locations 6 and 7. A positive correlation of CSV was observed with IgA and IgG concentrations from 12 h and 6 h post‐parturition, respectively (P < 0.05). The results suggest that anterior teats secrete greater volumes of colostrum and that these tend to contain higher IgA and IgG than posteriors teats.     

Application of long-term collected data for conservation: Spatio-temporal patterns of mortality in Japanese serow

Monitoring the mortality of wildlife provides basic demographic information to support management plan preparation. The utility of mortality records for conservation measures was investigated in the Japanese serow, focusing on temporal trends and spatial distribution. Using the mortality records of Japanese serow from 2006 to 2018 in Gifu prefecture, cause-specific mortality was categorized into five groups (disease, accident, vehicle collision, parapoxvirus infection, and unknown), and the sex ratios were examined. A state space model was used to analyze the time series for the monthly mortalities, and kernel estimation was used for the spatial distribution of the parapoxvirus infection. Land cover type around the detection point was also reported. Disease, accident, and vehicle collision mortality were similar, and 30% of mortality was of anthropogenic origin. The number of mortality records for males was higher, and the larger home range of males could account for this. The state space model showed moderate increases in monthly mortalities over time and a seasonal variation with the highest level in spring and lowest in winter. Land cover analysis demonstrated a temporal increase in the proportion of human settlement areas, suggesting the change of the Japanese serow habitat. The proximity of Japanese serow to human settlements contributed to increase in mortality records. The point pattern analysis indicated spatial clustering for parapoxvirus infection in the area where an epidemic had occurred in the past. Several measures are recommended; however, mortality records can help develop improved conservation plan.     

Comparison of protein chemical and physicochemical properties of rapeseed cruciferin with those of soybean glycinin

Rapeseeds contain cruciferin (11S globulin), napin (2S albumin), and oleosin (oil body protein) as major seed proteins. The effects of oil expression and drying conditions on the extraction of these proteins from rapeseed meal were examined. The conditions strongly affected the extraction of oleosin and only weakly affected the extraction of cruciferin and napin. The protein chemical and physicochemical properties of cruciferin, the major protein present, were compared with those of glycinin (soybean 11S globulin) under various conditions. In general, cruciferin exhibited higher surface hydrophobicity, lower thermal stability, and lower and higher solubility at mu= 0.5 and mu = 0.08, respectively, than did glycinin. At the pHs (6.0, 7.6, and 9.0) and ionic strengths (mu= 0.08 and 0.5) examined, the emulsifying ability of cruciferin was worse than that of glycinin, except at mu= 0.08 and pH 7.6. The emulsifying abilities of cruciferin and glycinin did not correlate with thermal stability and surface hydrophobicity. Higher protein concentration, higher heating temperature, higher pH, and lower ionic strength were observed to produce harder gels from cruciferin. Gel hardness partly correlated with the structural stability of cruciferin.     

Structure-physicochemical function relationships of soybean glycinin at subunit levels assessed by using mutant lines

Glycinin is a hexameric protein composed of five kinds of subunits. The subunits are classified into two groups, group I (A1aB1b, A1bB2, and A2B1a) and group II (A3B4 and A5A4B3). We purified four mutant glycinins composed of only group I subunits (group I-glycinin), only group II subunits (group II-glycinin), only A3B4 (A3B4-glycinin), and only A5A4B3 (A5A4B3-glycinin) from mutant soybean lines. The physicochemical properties of these glycinin samples were compared with those of the normal glycinin (11S) composed of five kinds of subunits. The thermal stabilities (as measured by thermal denaturation midpoint temperatures) of 11S, group I-glycinin, and group II-glycinin were similar to each other, although that of A3B4-glycinin was significantly lower than those of the others. The orders of aromatic and aliphatic surface hydrophobicities were the same: A3B4-glycinin > group II-glycinin > A5A4B3-glycinin > 11S > group I-glycinin. The solubility of 11S as a function of pH at mu = 0.5 was governed by that of group I-glycinin and followed this order at acidic pH: 11S = group I-glycinin > A3B4-glycinin > group II-glycinin = A5A4B3-glycinin. The order of emulsifying abilities was A5A4B3-glycinin > group II-glycinin > A3B4-glycinin > 11S > group I-glycinin. This order was consistent with that of the length of their hypervariable regions. Except for this relationship, there was no significant relationship among the other physicochemical properties of the mutant glycinins.     

Chronic Peripheral Administration of Kappa-Opioid Receptor Antagonist Advances Puberty Onset Associated with Acceleration of Pulsatile Luteinizing Hormone Secretion in Female Rats

Puberty in mammals is timed by an increase in gonadotropin-releasing hormone (GnRH) secretion. Previous studies have shown involvement of the two neuropeptides, kisspeptin and neurokinin B (NKB), in controlling puberty onset. Little is known about the role of the other key neuropeptide, dynorphin, in controlling puberty onset, although these three neuropeptides colocalize in the arcuate kisspeptin neurons. The arcuate kisspeptin neuron, which is also referred to as the KNDy neuron, has recently been considered to play a role as an intrinsic source of the GnRH pulse generator. The present study aimed to determine if attenuation of inhibitory dynorphin-kappa-opioid receptor (KOR) signaling triggers the initiation of puberty in normal developing female rats. The present study also determined if stimulatory NKB-neurokinin 3 receptor (NK3R) signaling advances puberty onset. Female Wistar-Imamichi rats were weaned and intraperitoneally implanted with osmotic minipumps filled with nor-binaltorphimine (nor-BNI), a KOR antagonist, or senktide, a NK3R agonist, at 20 days of age. Fourteen days of intraperitoneal infusion of nor-BNI or senktide advanced puberty onset, manifested as vaginal opening and the first vaginal estrus in female rats. Frequent blood sampling showed that nor-BNI significantly increased luteinizing hormone (LH) pulse frequency at 29 days of age compared with vehicle-treated controls. Senktide tended to increase this frequency, but its effect was not statistically significant. The present results suggest that the inhibitory input of dynorphin-KOR signaling plays a role in the prepubertal restraint of GnRH/LH secretion in normal developing female rats and that attenuation of dynorphin-KOR signaling and increase in NKB-NK3R signaling trigger the onset of puberty in female rats.     

Canine intestinal mast cell tumor with c-kit exon 8 mutation responsive to imatinib therapy

A canine intestinal mast cell tumor with splenic metastasis was treated with imatinib. The intestinal and metastatic tumor masses markedly decreased following treatment although the clinical response was short lasting. A c-kit internal tandem duplication mutation, c.1250_1261dup, which causes an insertion of four amino acids in KIT, was identified in cDNA isolated from the tumor cells. The phosphorylation status of the mutant KIT and the effect of imatinib on its phosphorylation were examined using 293 cells transfected with c-kit carrying the c.1250_1261dup mutation. This mutation caused ligand-independent phosphorylation of KIT, which was suppressed by imatinib. Inhibition of constitutively activated mutant KIT with imatinib could underlie the tumor response in this dog.     

Cell proliferation potency is independent of FGF4 signaling in trophoblast stem cells derived from androgenetic embryos

We previously established trophoblast stem cells from mouse androgenetic embryos (AGTS cells). In this study, to further characterize AGTS cells, we compared cell proliferation activity between trophoblast stem (TS) cells and AGTS cells under fibroblast growth factor 4 (FGF4) signaling. TS cells continued to proliferate and maintained mitotic cell division in the presence of FGF4. After FGF4 deprivation, the cell proliferation stopped, the rate of M-phase cells decreased, and trophoblast giant cells formed. In contrast, some of AGTS cells continued to proliferate, and the rate of M-phase cells did not decrease after FGF4 deprivation, although the other cells differentiated into giant cells. RO3306, an ATP competitor that selectively inhibits CDK1, inhibited the cell proliferation of both TS and AGTS cells. Under RO3306 treatment, cell death was induced in AGTS cells but not in TS cells. These results indicate that RO3306 caused TS cells to shift mitotic cell division to endoreduplication but that some of AGTS cells did not shift to endoreduplication and induced cell death. In conclusion, the paternal genome facilitated the proliferation of trophoblast cells without FGF4 signaling.     

Investigating environmental factors that cause extreme gluten quality deficiency in winter wheat (Triticum aestivum L.)

Unstable breadmaking quality of wheat due to environmental influence has been a problem for Norwegian milling industries. Large variation in gluten quality was observed from field trials with Norwegian winter wheat conducted in several locations between 2005 and 2013. Moreover, extremely poor gluten quality was observed in several locations in the 2007 and 2011 season, and indicated almost complete loss of breadmaking quality. To investigate the environmental factors which cause extremely weak gluten, gluten proteins were characterized in samples selected within the 2011 season. The results revealed that the proportion of large glutenin polymers decreased in wheat samples with extremely weak gluten. Moreover, re-polymerization of large glutenin polymers, which normally occur during the resting period of a dough, did not take place in gluten prepared from these samples. Incubation of total proteins extracted from these samples in an in vitro system showed a drastic degradation of gluten proteins indicating protease activities. The origin of the proteases remains unclear; however, exogenous proteases derived from Fusarium spp. seem to play a key role for protein degradation, and thus causing severe quality deficiency. A genotypic difference was found between the two cultivars and one of them had higher resistance against the factors influencing gluten quality in negative way.     

Development of semidwarf breeding line with shattering resistance and preharvest-sprouting resistant in buckwheat (Fagopyrum esculentum)

An important breeding issue in buckwheat is to increase its resistance to lodging, which can result in the loss of yield and quality of buckwheat foods. We developed the semidwarf buckwheat ‘Kyukei 50’, which has a short plant height and a strong lodging resistance. The internode length of ‘Kyukei 50’ was shorter than that of the summer-sown standard variety ‘HITACHIAKISOBA’. Progeny analysis revealed that the semidwarf trait was dominated by at least one recessive gene. Compared with ‘HITACHIAKISOBA’, in ‘Kyukei 50’, the time of maturation was earlier, and the pre-harvest sprouting resistance was the same, indicating that ‘Kyukei 50’ is suitable for sowing in both spring and summer. ‘Kyukei 50’ exhibits the ‘green flower type’ shattering resistance trait and, therefore, has a thick pedicel; breaking tensile strength is approximately two-fold stronger than that of ‘HITACHIAKISOBA’. The yield of ‘Kyukei 50’ is the same as that of ‘HITACHIAKISOBA’. In addition, the lowest seed height of ‘Kyukei 50’ was >17 cm. These results indicate that the ‘Kyukei 50’ is a promising breeding line for lodging resistance and loss of harvesting machinery.