Production of cloned pigs from salivary gland-derived progenitor cells

To achieve tissue stem cell transplantation in clinical settings, translational studies using large animal models are essential to confirm the efficacy and safety of therapy. Therefore, with the ultimate objective of constructing a porcine model of stem cell transplantation in the present study we attempted to clone pigs using porcine salivary gland-derived progenitor cells (pSGPs) as nuclear donors. Normal chromosomal compositions of pSGPs were maintained after five to eight passages (73%, 41 of 56). Cell cycle was efficiently synchronized in G(0)/G(1) phase after 2 days of serum-starved culture (79%). Characteristics of multipotent pSGPs, that is, CD49f and intracellular laminin staining patterns, were unchanged after serum-starved culture. Developmental rate of blastocysts from embryos reconstructed using pSGPs as nuclear donors was significantly higher when compared to embryos reconstructed using fetal fibroblasts (27.7%, 38 of 137 vs. 12.8%, 17 of 138; p < 0.05). When a total of 615 reconstructed embryos were transplanted into four recipient gilts, all gilts became pregnant and produced 12 piglets. These findings suggest that pSGPs represent appropriate donor cells for porcine somatic cell nuclear transfer.     

Enhancement of Thermal Properties of Polyvinylpyrrolidone (PVP)-Coated Silver Nanoparticles by Using Plasmid DNA and their Localized Surface Plasmon Resonance (LSPR) Characteristics

In this paper, the enhancement of thermal properties of polymer-coated silver nanoparticles by the addition of plasmid DNA is described. Nanoparticles of noble metals such as gold and silver possess specific characteristics by virtue of their quantum size effects. Therefore, noble metal nanoparticles are used for chemical sensing and biosensing applications based on their localized surface plasmon resonance absorption that can be measured in the visible region. The polyvinylpyrrolidone (PVP)-coated noble metal nanoparticles, in particular, with high dispersion ability in water, offer several advantages for sensing applications. However, some difficulties are encountered in the use of these PVP-coated noble metal nanoparticles for sensing applications due to their poor thermal properties. To improve the thermal properties of PVP-coated noble metal nanoparticles, we found that the addition of plasmid DNA to PVP-coated silver nanoparticles enhances their thermal properties due to good thermal stability of DNA. The introduction of plasmid DNA into PVP-coated silver nanoparticle dispersion enhanced the thermal properties through the formation of a complex between the nanoparticles and plasmid DNA. Furthermore, other polymers such as proteins and polyethylene glycol did not enhance the thermal properties of PVP-coated silver nanoparticles. Thus, the PVP-coated silver nanoparticle–plasmid DNA complex with enhanced thermal properties has a great potential for use in medical and drug delivery applications.     

Improved genome assembly and evidence-based global gene model set for the chordate Ciona intestinalis: new insight into intron and operon populations

Background

The draft genome sequence of the ascidian Ciona intestinalis, along with associated gene models, has been a valuable research resource. However, recently accumulated expressed sequence tag (EST)/cDNA data have revealed numerous inconsistencies with the gene models due in part to intrinsic limitations in gene prediction programs and in part to the fragmented nature of the assembly.

Results

We have prepared a less-fragmented assembly on the basis of scaffold-joining guided by paired-end EST and bacterial artificial chromosome (BAC) sequences, and BAC chromosomal in situ hybridization data. The new assembly (115.2 Mb) is similar in length to the initial assembly (116.7 Mb) but contains 1,272 (approximately 50%) fewer scaffolds. The largest scaffold in the new assembly incorporates 95 initial-assembly scaffolds. In conjunction with the new assembly, we have prepared a greatly improved global gene model set strictly correlated with the extensive currently available EST data. The total gene number (15,254) is similar to that of the initial set (15,582), but the new set includes 3,330 models at genomic sites where none were present in the initial set, and 1,779 models that represent fusions of multiple previously incomplete models. In approximately half, 5'-ends were precisely mapped using 5'-full-length ESTs, an important refinement even in otherwise unchanged models.

Conclusion

Using these new resources, we identify a population of non-canonical (non-GT-AG) introns and also find that approximately 20% of Ciona genes reside in operons and that operons contain a high proportion of single-exon genes. Thus, the present dataset provides an opportunity to analyze the Ciona genome much more precisely than ever.     

Limited distribution of natural cyanamide in higher plants: occurrence in Vicia villosa subsp. varia, V. cracca, and Robinia pseudo-acacia

Cyanamide (NH2CN) has recently been proven to be a natural product, although it has been synthesized for over 100 years for agricultural and industrial purposes. The distribution of natural cyanamide appears to be limited, as indicated by our previous investigation of 101 weed species. In the present study, to investigate the distribution of natural cyanamide in Vicia species, we monitored the cyanamide contents in V. villosa subsp. varia, V. cracca, and V. amoena during their pre-flowering and flowering seasons. It was confirmed that V. cracca was superior to V. villosa subsp. varia in accumulating natural cyanamide, and that V. amoena was unable to biosynthesize this compound under laboratory condition examined. The localization of cyanamide in the leaves of V. villosa subsp. varia seedlings was also clarified. In a screening study to find cyanamide-biosynthesizing plants, only Robinia pseudo-acacia was found to contain cyanamide among 452 species of higher plants. We have investigated 553 species to date, but have so far found the ability to biosynthesize cyanamide in only three species, V. villosa subsp. varia, V. cracca and R. pseudo-acacia.     

Combining hot-compressed water and ball milling pretreatments to improve the efficiency of the enzymatic hydrolysis of eucalyptus

Background  

Lignocellulosic biomass such as wood is an attractive material for fuel ethanol production. Pretreatment technologies that increase the digestibility of cellulose and hemicellulose in the lignocellulosic biomass have a major influence on the cost of the subsequent enzymatic hydrolysis and ethanol fermentation processes. Pretreatments without chemicals such as acids, bases or organic solvents are less effective for an enzymatic hydrolysis process than those with chemicals, but they have a less negative effect on the environment.     

Ground-surface application of pheromones through a mini-dispenser for mating disruption of the white grub beetle <Emphasis Type="Italic">Dasylepida ishigakiensis</Emphasis> (Coleoptera: Scarabaeidae)

The effect of mating disruption by the ground-surface application of 2-cm-long dispensers (mini-dispensers) of 2-butanol against the white grub beetle Dasylepida ishigakiensis Niijima et Kinoshita (Coleoptera: Scarabaeidae) was examined in sugarcane fields on the Miyako Island, Okinawa, Japan. Mating rates and male catches with sex pheromone traps were reduced to a low level comparable to that obtained from a conventional method in which rope dispensers (25 m) were hung at a height of ca. 30 cm along the sugarcane ridges. Both mating rates and male catches were reduced with increasing number of treated mini-dispensers. These results suggest that by using mini-dispensers the amounts of synthetic sex pheromone and plastic resin can be reduced to 1/10–1/5 and 1/6–1/3, respectively, of their conventional application with rope-type dispensers, without impairing the efficiency of mating disruption in this beetle. Furthermore, the amount of labor required for the application of this method is expected to be greatly reduced compared to the rope-type dispenser method.