New type of heat shock protein 70 homologue gene abounds in the genomic sequence of kuruma shrimp Marsupenaeus japonicus

Heat shock proteins (HSPs) are a group of highly conserved molecular chaperones. Shrimp HSPs have recently been a topic of increasing interest because of their roles in shrimp immunity and homeostasis. In penaeid shrimp, HSP70s and the cognate forms, heat shock cognate (HSC) 70s, have been reported, but their responses towards various stimulations are different. We found a novel type HSP70 (MjHSP70-2) from the hyperexpansion of the large segmental duplication that is present in kuruma shrimp Marsupenaeus japonicus, which shows about 60 % identity with reported shrimp HSP70s. In a phylogenetic tree, MjHSP70-2 formed a sister clade with eukaryote HSP70 family while MjHSP70 was located close to the shrimp HSP70 and HSC70 group. MjHSP70-2 gene expression was not significantly increased by heat shock or pathogen challenge by Vibrio penaeicida, but it was significantly increased by infection with white spot syndrome virus. In contrast, MjHSP70 gene expression was increased by heat shock but decreased by infection with V. penaeicida. The kuruma shrimp genome was found to have 400-fold more copies of the MjHSP70-2 gene than the putative single-copy gene transglutaminase. In conclusion, our results reveal the presence of a novel type HSP70 gene, HSP70-2, from kuruma shrimp. There are multiple forms of HSP70 in crustaceans, and these HSP70s behave differently under various stressors.     

Aspergillus Sydowii Marine Fungal Bloom in Australian Coastal Waters,Its Metabolites and Potential Impact on Symbiodinium Dinoflagellates

Dust has been widely recognised as an important source of nutrients in the marine environment and as a vector for transporting pathogenic microorganisms. Disturbingly, in the wake of a dust storm event along the eastern Australian coast line in 2009, the Continuous Plankton Recorder collected masses of fungal spores and mycelia (~150,000 spores/m³) forming a floating raft that covered a coastal area equivalent to 25 times the surface of England. Cultured A. sydowii strains exhibited varying metabolite profiles, but all produced sydonic acid, a chemotaxonomic marker for A. sydowii. The Australian marine fungal strains share major metabolites and display comparable metabolic diversity to Australian terrestrial strains and to strains pathogenic to Caribbean coral. Secondary colonisation of the rafts by other fungi, including strains of Cladosporium, Penicillium and other Aspergillus species with distinct secondary metabolite profiles, was also encountered. Our bioassays revealed that the dust-derived marine fungal extracts and known A. sydowii metabolites such as sydowic acid, sydowinol and sydowinin A adversely affect photophysiological performance (F_v/F_m) of the coral reef dinoflagellate endosymbiont Symbiodinium. Different Symbiodinium clades exhibited varying sensitivities, mimicking sensitivity to coral bleaching phenomena. The detection of such large amounts of A. sydowii following this dust storm event has potential implications for the health of coral environments such as the Great Barrier Reef.     

Sat-BSA: an NGS-based method using local de novo assembly of long reads for rapid identification of genomic structural variations associated with agronomic traits

Advances in next generation sequencing (NGS)-based methodologies have accelerated the identifications of simple genetic variants such as point mutations and small insertions/deletions (InDels). Structural variants (SVs) including large InDels and rearrangements provide vital sources of genetic diversity for plant breeding. However, their analysis remains a challenge due to their complex nature. Consequently, novel NGS-based approaches are needed to rapidly and accurately identify SVs. Here, we present an NGS-based bulked-segregant analysis (BSA) technique called Sat-BSA (SVs associated with traits) for identifying SVs controlling traits of interest in crops. Sat-BSA targets allele frequencies at all SNP positions to first identify candidate genomic regions associated with a trait, which is then reconstructed by long reads-based local de novo assembly. Finally, the association between SVs, RNA-seq-based gene expression patterns and trait is evaluated for multiple cultivars to narrow down the candidate genes. We applied Sat-BSA to segregating F₂ progeny obtained from crosses between turnip cultivars with different tuber colors and successfully isolated two genes harboring SVs that are responsible for tuber phenotypes. The current study demonstrates the utility of Sat-BSA for the identification of SVs associated with traits of interest in species with large and heterozygous genomes.     

Molecular characterization of Cryptosporidium parvum detected in Japanese black and Holstein calves in Iwate Prefecture and Tanegashima Island,Kagoshima Prefecture,Japan

Cryptosporidium oocysts were found in 43 out of 77 calves from two farms in Iwate Prefecture and nine farms on Tanegashima Island, Kagoshima Prefecture, Japan. The DNA fragments of 18S ribosomal RNA (18S rRNA) gene were amplified by a nested PCR from 43 oocyst-positive as well as one oocyst-negative samples. All of them were precisely identified as C. parvum by analyzing the nucleotide sequences of the 18S rRNA gene. C. parvum oocyst-positive calves ranged in age from 6 to 13 days old and significantly have watery diarrhea (P<0.05). Sequences of the gene encoding the 60-kDa glycoprotein (GP60) in 43 Cryptosporidium oocyst-positive samples were identical to that of the zoonotic IIaA15G2R1 subtype. We therefore suggest that calves could be potential sources of C. parvum infections in humans.     

Estimation of the economic value of herd‐life length based on simulated changes in survival rate

Functional traits are an important aspect of long‐term breeding strategies for dairy cattle. In this regard, it is necessary to develop simple methods for estimating the economic value of herd life. In this study, the economic daily value of herd life was estimated when survival rate varied between ?0.05 and 0.05 from the basal survival rate. The extension days per survival rate were 26.5 days in Hokkaido and 20.3 days in other regions. The increases in values of annual income per day of herd life were 95.18 yen in Hokkaido and 101.80 yen in other regions. The relative economic weights of milk yield to herd life per genetic standard deviation were 0.668 in Hokkaido and 1.03 in other regions. Estimated increments in yearly profits based on young sire selection for herd life were 963 yen in Hokkaido and 1,030 yen in other regions. The estimated increments in annual profits based on young sire selection for milk yield were 1,268 yen in Hokkaido and 2,097 yen in other regions. Given that economic value was linearly correlated with herd‐life length, the linear regression coefficients between these factors could be used to estimate the economic value of herd‐life length.     

Nitrogen balance during compensatory growth when changing the levels of dietary lysine from deficiency to sufficiency in growing pigs

Two experiments were conducted to elucidate the nitrogen (N) balance of pigs exhibiting compensatory growth when changing the dietary lysine levels from deficiency to sufficiency. Experiment 1 elucidated whether pigs exhibited compensatory growth with dietary lysine sufficiency. Twenty 6‐week‐old males were assigned to one of two treatments: control and LC (lysine and control). Control pigs were fed a control diet throughout the 24‐day experimental period, whereas LC pigs were fed a low lysine diet until day 21 of the experiment, followed by the control diet until the end of experiment. The dietary lysine sufficiency treatment induced an 80% increase in the growth rate of LC pigs (P < 0.05). Experiment 2 focused on the N balance of pigs that exhibited compensatory growth with dietary lysine sufficiency. Eighteen 6‐week‐old males were assigned to one of three treatments: control, LC, and LL (low lysine). LL pigs were fed a low lysine diet throughout the 24‐day experimental period. Pigs that exhibited compensatory growth with dietary lysine sufficiency tended to retain a higher amount of N than control pigs (P = 0.10). These finding suggest that the compensatory growth induced in pigs by dietary lysine sufficiency was partly attributable to a higher level of N retention.     

CR1aa-卵丘细胞共培养牛体外受精卵的卵裂率及囊胚率

牛卵母细胞用5％CS的TCM－199培养液体外成熟培养（IVM）22h；以BO液＋咖啡因作精子获能处理1.5h；BO液＋BSA的培养液体外受精（IVF）5h；受精卵（含卵丘细胞）用5％CS的CR1aa培养液在5％CO2、955空气、38.5℃、饱和湿度的培养环境中体外培养（IVC）7－8d，结果受精卵裂率为72.4%（56.3%－81.0%），囊胚率23.7%(12.5%-40.9%）。     

Dietary supplementation with cellooligosaccharide improves growth performance in weanling pigs

Nondigestible oligosaccharides are not digested in the small intestine, but are fermented by bacteria colonizing in the large intestine. Physiological effects of non‐digestible oligosaccharides have been considered to be conferred by the fermentation of bacteria colonizing in the large intestine. Because cellooligosaccharide is a non‐digestible oligosaccharide, various physiological effects are expected. However, physiological functions of cellooligosaccharide are not well understood. This experiment was conducted to clarify the effect of dietary supplementation with cellooligosaccharide on the growth performance in weanling pigs. The result showed that average daily gain was significantly higher (P < 0.05) in pigs fed a diet supplemented with cellooligosaccharide than in pigs without cellooligosaccharide. There was a tendency to increasing average daily feed intake in pigs with cellooligosaccharide, though the significant difference was not detected (P = 0.18). Feed efficiency and nutrient digestibility of feces and ileum were not changed by feeding cellooligosaccharide. In addition, blood urea nitrogen was significantly higher (P < 0.05) in pigs fed the diet supplemented with cellooligosaccharide than in pigs without cellooligosaccharide. The concentrations of acetic and iso‐valeric acids in the cecum of pigs fed the diet with cellooligosaccharide tended to be higher (P < 0.10) than those without cellooligosaccharide. The results obtained in this study demonstrated that dietary supplementation with cellooligosaccharide improves growth performance in weanling pigs.     

Level of VERNALIZATION 1 expression is correlated with earliness in extra early-flowering mutant wheat lines

Four extra early-flowering mutants, named extra early-flowering1 (exe1), exe2, exe3, and exe4, were identified in Triticum monococcum strain KU104-1 following heavy-ion beam mutagenesis. The four exe mutants fell into two groups, namely Type I (moderately extra early-flowering type; exe1 and exe3) and Type II (extremely extra early-flowering type; exe2 and exe4). Analysis of plant development in a growth chamber showed that the speed of leaf emergence was accelerated in exe mutants at the reproductive stage compared to wild-type (WT) plants. The speed of leaf emergence was faster in Type II than Type I plants. Analysis of VERNALIZATION 1 (VRN1), a flowering promoter gene, showed that it was more highly expressed in seedlings at early developmental stages in Type II mutants than Type I mutants. These findings indicate that the difference in earliness between Type I and Type II mutants is associated with the level of VRN1 expression. The original KU104-1 is an einkorn wheat strain that carries a null allele of the VRN2 gene, a repressor of flowering. Thus, our results indicate that the level of VRN1 expression controls earliness in exe mutants independently of VRN2.