Long-term blast control in high eating quality rice using multilines.

Combining genetic heterogeneity and crop homogeneity serves a dual purpose: disease control and maintaining harvest quality. Multilines, which consist of a genetically uniform mixture of plants, have the potential to suppress disease while maintaining eating quality, yet practical methods that facilitate commercial use over large geographical areas are lacking. Here, we describe effective rice multiline management based on seed mixture composition changes informed by monitoring virulent blast races in Niigata Prefecture, Japan. The most elite nonglutinous cultivar, Koshihikari, was converted into the multiline, Koshihikari BL (blast resistant lines) and planted on 94,000 ha in 2005. The most destructive rice disease, blast, was 79.4% and 81.8% less severe in leaves and panicles, respectively, during the 2005-2019 period compared to the year 2004. In addition, fungicidal application was reduced by two-thirds after the introduction of BL. Our results suggest that seed mixture diversification and rotation of resistant BL provides long-term disease control by avoiding virulent race evolution.

Fabrication of ferromagnetic nanoconstriction using atomic force microscopy nanoscratching.

Nanolithography used in conjunction with atomic force microscopy (AFM) has attracted considerable attention as a technique for fabricating nanoscale structures. To obtain nanostructures and devices, AFM nanoscratching was performed on a photoresist and on NiFe at various values of the applied force, scan speed, and number of scan cycles. The scratching process was carried out using a diamond-coated tip on NiFe and a Si tip on the photoresist. By conducting scratching processes on NiFe and on the photoresist, we investigated the dependence of the size of the scratched part on the scratching parameters. These results show that the width and depth of the scratched part increase as the applied force and number of scan cycles increase, but not as the scan speed increases. This means that it is possible to control the size of the scratched parts by adjusting the applied force and number of scan cycles. AFM nanoscratching was then used to directly fabricate a nanoconstricted area with a width of 139 nm and a cross-sectional area of less than 300 nm2 was fabricated.

Functional expression of carnitine/organic cation transporter OCTN1/SLC22A4 in mouse small intestine and liver.

Carnitine/organic cation transporter (OCTN1/SLC22A4) accepts various therapeutic agents as substrates in vitro and is expressed ubiquitously, although its function in most organs has not yet been examined. The purpose of the present study was to evaluate functional expression of OCTN1 in small intestine and liver, using octn1 gene knockout [octn1(-/-)] mice. After oral administration of [(3)H]ergothioneine ([(3)H]ERGO), a typical substrate of OCTN1, the amount of [(3)H]ERGO remaining in the small intestinal lumen was much higher in octn1(-/-) mice than in wild-type mice. In addition, uptake of [(3)H]ERGO by human embryonic kidney 293 cells heterologously expressing OCTN1 gene product and uptake of [(3)H]ERGO at the apical surface of intestinal everted sacs from wild-type mice were inhibited by OCTN1 substrates, tetraethylammonium and verapamil. Immunohistochemical analysis revealed that OCTN1 is localized on the apical surface of small intestine in mice and humans. These results suggest that OCTN1 is responsible for small intestinal absorption of [(3)H]ERGO. However, the plasma concentration of [(3)H]ERGO after oral administration was higher in octn1(-/-) mice than in wild-type mice, despite the lower absorption in octn1(-/-) mice. This was probably because of efficient hepatic uptake of [(3)H]ERGO, as revealed by integration plot analysis; the uptake clearance was close to the hepatic plasma flow rate. The uptake of [(3)H]ERGO by isolated hepatocytes was minimal, whereas [(3)H]ERGO uptake was observed in isolated nonparenchymal cells. This finding is consistent with immunostaining of OCTN1 in liver sinusoids. Thus, our results indicate that OCTN1 is functionally expressed in nonparenchymal liver cells.

Gene knockout and metabolome analysis of carnitine/organic cation transporter OCTN1.

PURPOSE: Solute carrier OCTN1 (SLC22A4) is an orphan transporter, the physiologically important substrate of which is still unidentified. The aim of the present study was to examine physiological roles of OCTN1. METHODS: We first constructed octn1 gene knockout (octn1 ( -/- )) mice. Metabolome analysis was then performed to identify substrates in vivo. The possible association of the substrate identified with diseased conditions was further examined. RESULTS: The metabolome analysis of blood and several organs indicated complete deficiency of a naturally occurring potent antioxidant ergothioneine in octn1 ( -/- ) mice among 112 metabolites examined. Pharmacokinetic analyses after oral administration revealed the highest distribution to small intestines and extensive renal reabsorption of [(3)H]ergothioneine, both of which were much reduced in octn1 ( -/- ) mice. The octn1 ( -/- ) mice exhibited greater susceptibility to intestinal inflammation under the ischemia and reperfusion model. The blood ergothioneine concentration was also much reduced in Japanese patients with Crohn's disease, compared with healthy volunteers and patients with another inflammatory bowel disease, ulcerative colitis. CONCLUSIONS: These results indicate that OCTN1 plays a pivotal role for maintenance of systemic and intestinal exposure of ergothioneine, which could be important for protective effects against intestinal tissue injuries, providing a possible diagnostic tool to distinguish the inflammatory bowel diseases.

Involvement of carnitine/organic cation transporter OCTN2 (SLC22A5) in distribution of its substrate carnitine to the heart.

This study was designed to clarify the pharmacological role of carnitine/organic cation transporter (Octn) family members in mouse heart. Immunohistochemical analysis revealed that Octn1 was exclusively expressed on endothelial cells in blood vessels. Octn2 was detected on the plasma membrane of cardiac muscle cells by immunoelectron microscopy. Octn3 was not detected in the heart. Integration plot analysis showed that coadministration of unlabeled L-carnitine reduced distribution of L-[3H]carnitine to the heart. L-[3H]Carnitine uptake in heart slices was reduced by carnitine analogs and various Octn2 substrates. L-[3H]Carnitine uptake by heart slices from juvenile visceral steatosis (jvs) mice, which have a hereditary octn2 gene deficiency, was negligible. Distribution of [3H]quinidine, another Octn2 substrate, to the heart was not reduced by L-carnitine, and [3H]quinidine uptake in heart slices was Na(-)-independent and inhibited by cationic drugs, but not carnitine analogs. [3H]Quinidine uptake by heart slices from jvs mice was similar to that of wild-type mice. These results demonstrate that OCTN2 is functionally expressed on the plasma membrane of muscle cells and is involved in distribution of carnitine to the heart. Some mechanism(s) other than OCTN2 is involved in the distribution of quinidine to the heart.