gw2 mutation increases grain width and culm thickness in rice (Oryza sativa L.).

Grain size is one of the most important agricultural traits in rice. To increase grain yield, we screened a large grain mutant from mutants with the 'Koshihikari' background. As a result, we obtained a mutant, KEMS39, that has a large grain size and increased yield. Cultivation tests revealed that this mutant had improved lodging resistance with thicker internodes. Next-generation sequencing analysis revealed the presence of a 67 bp deletion in the GW2 mRNA, owing to a mutation in the 3' splice site of the sixth intron of the GW2 gene. To determine whether this mutation was responsible for the larger grain and thicker internodes, we performed gene editing and obtained a mutant with a 7 bp deletion, including this 3' splice site. As this gw2 mutant had large grains and thicker internodes, the causal gene of KEMS39 was determined as GW2. Thicker internodes are attributed to the pleiotropic effect of gw2 mutation. On the basis of these results, we conclude that gw2 mutation has the potential to be an important genetic resource with the ability to achieve a well-balanced and high-yielding effect that simultaneously improves grain productivity and lodging resistance.

Possible relationship between the risk of Japanese bladder cancer cases and the CYP4B1 genotype.

Cytochrome P450 4B1 (CYP4B1) is involved in the metabolism of several xenobiotics, such as 2-aminofluorene, 2-naphthylamine and benzidine. CYP4B1 allelic variants CYP4B1*1-*7 were recently identified. We thus hypothesized that CYP4B1 genotypes may modify bladder cancer risk. We examined the CYP4B1 genotypes in 169 bladder cancer cases and 190 hospital controls using a hybridization probe assay. Among the CYP4B1 genotypes observed, the most frequent genotypes in both the groups were CYP4B1*1/*1, *1/*2, *1/*3 and *2/*2. Logistic regression analysis revealed that the subjects carrying the CYP4B1*1/*2 or *2/*2 genotypes had a 1.75-fold increased risk of bladder cancer (95% CI=1.03-2.95, P = 0.038) compared with the subjects carrying the CYP4B1*1/*1 genotype. We demonstrated the first genetic study regarding the association of CYP4B1 with bladder cancer. Our results suggest that CYP4B1 genotypes might have an effect on the risk of bladder cancer.

Microbial enantioselective reduction of acetylpyridine derivatives.

The microbial enantioselective reduction of acetylpyridine derivatives was studied. Many microorganisms were found to reduce 5-acetylfuro[2,3-c]pyridine (AFP) to (S)-5-(1-hydroxyethyl)furo[2,3-c]-pyridine (FPH). Candida maris IFO10003 reduced AFP to (R)-FPH with high enantioselectivity. The microbial reduction reaction was optimized. The aeration conditions and glucose concentration affected the yield and stereoselectivity. The cells accumulated 17.5 g/l (107 mM) of (R)-FPH with a 99% yield and 97% enantiomeric excess (e.e.). A cell-free extract of C. maris accumulated 91.5 g/l (559 mM) with over 99% e.e. with enzymatic NADH regeneration. (R)-FPH is an important intermediate for the synthesis of HIV reverse-transcriptase inhibitor, and other optically active 1-(pyridyl)ethanol derivatives are versatile chiral building blocks for asymmetric synthesis.