Hideto Mori

Lewy bodies are ubiquitinated

SummaryThe nature of Lewy bodies (LBs) in the brain stem and cerebral cortex in five cases of diffuse Lewy body disease and one case of Parkinsons disease with dementia were investigated immunocytochemically with various antibodies to cytoskeletal proteins, paired helical filaments (PHF) and ubiquitin. Antibodies to 200-kDa component of neurofilament, tau and PHF showed no significant reactions with most of LBs. Antibodies to high-molecular weight microtubule-associated proteins (HMWMAPs) moderately stained the periphery of a few of LBs. A monoclonal antibody to PHF (DF2) which recognizes ubiquitin, and polyclonal antibodies to ubiquitin immunostained virtually all of the typical and cortical LBs as intensely as Alzheimers neurofibrillary tangles and senile plaque neurites: the periphery of LBs was darkly stained, whereas the central core of typical LBs and central zone of cortical LBs were less intensely stained or remained unstained. Immunoelectron microscopy of the LBs with DF2 revealed that immune reaction products were located on the filaments exclusively in the periphery of LBs, but not on those in the center. These findings suggest that both types of LBs are immunocytochemically indistinguishable despite some structural differences, and that peripherally located filaments in LBs are tagged with ubiquitin, an element required for the ATP-dependent proteolysis system in the cell. Antibodies to ubiquitin are the most useful marker of LBs ever known.

Biochemical preparations of both the enantiomers of methyl 3-hydroxypentanoate and their conversion to the enantiomers of 4-hexanolide, the pheromone of trogoderma glabrum

Abstract Both the enantiomers of methyl 3-hydroxypentanoate were prepared by microbial asymmetric reduction of 3-oxopentanoic esters. Conversion of methyl 3-hydroxypentanoate to 4-hexanolide, the pheromone of Trogoderma glabrum, was achieved.

Synthesis of both the enantiomers of juvenile hormone III

Abstract Both the enantiomers (∼100 % e.e.) of juvenile hormone III [methyl (2 E , 6 E )-10, 11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate, JH III) were synthesized employing ( s )-3-hydroxy-2,2-dimethylcyclohexanone as a single chiral source.

Synthesis of (1s,5r)-karahana ether and (1s,5r)-karahana lactone, the optically active forms of unique monoterpenes wit

Abstract (1 S ,5 R )-(-)-Karahana ether (8,8-dimethyl-2-methylene-6-oxabi-cyclo[ 3.2.1]octane) and (1 S ,5 R )-(-)-karahana lactone (8,8-dimethyl-2-methylene-6-oxabicyclo [3.2.1]octan-7-one) were synthesized from ( S )-3-hydroxy-2,2-dimethylcyclo-hexanone. The natural karahana lactone was shown to be almost racemic ( ca . 1.3 % e.e.).

Synthesis of both the enantiomers of q-methyl pisiferic acid, a mite growth regulator isolated from chamaecyparis pisifera endl

Abstract Both the enantiomers of O -methyl pisiferic acid (12-methoxyabieta-8, 11,13-trien-20-oic acid) were synthesized from ( S )-3-hydroxy-2,2-dimethylcyclo-hexanone.

Synthesis of (2S,4aS,8aR)-(-)-1,1,4a-trimethyl-2-decalol, an inhibitor of steroid biosynthesis

Abstract (2 S ,4a S ,8a R )-(-)-1,1,4a-Trimethyl-2-decalol was synthesized from ( S )-(+)-3-hydroxy-2, 2-dimethylcyclohexanone in 31 % overall yield in 8 steps.

Curly fibers are tau-positive strands in the pre- and post-synaptic neurites, consisting of paired helical filaments: observations by the freeze-etch and replica method.

SummaryThe ultrastructure of the curly fibers was examined by the transmission and immunoelectron microscopy as well as by the rapid-freeze, deep-etch and replica method. The curly fibers consisted mainly of paired helical filaments (PHF) in the neuropils, both pre- and post-synaptic. On the deep-etch replicas, PHF in the neurites had similar dimensions to those of Alzheimers neurofibrillary tangles in the nerve cell somata, having the width of 28 to 36 nm. The two component filaments, 14 to 18 nm in width, were twisted left-handedly with about 70- to 90-nm intervals. There were also cross-bridging fibrils of about 6 nm in diameter connecting the neighboring PHF.

Engineered CRISPR-Cas9 nuclease with expanded targeting space

Expanding the targeting space of Cas9 CRISPR-Cas9 associates with a guide RNA to target and cleave a specific DNA site next to a protospacer adjacent motif (PAM). Streptococcus pyogenes Cas9 (SpCas9), the one most often used for genome editing, only recognizes the NGG sequence (where N is any nucleobase) as the PAM, which restricts regions in the genome that can be targeted. To address this limitation, Nishimasu et al. created a SpCas9 variant that recognizes NG rather than NGG. The SpCas9-NG variant increased the targeting range, had a specificity similar to that of the wild-type enzyme, and could be used with a base editor. Thus, SpCas9-NG is a powerful addition to the CRISPR-Cas9 genome engineering toolbox and will be useful in a broad range of applications, from basic research to clinical therapeutics. Science, this issue p. 1259 An engineered CRISPR-Cas9 nuclease increases the range of genomic sequences that can be targeted in Cas9-mediated genome engineering. The RNA-guided endonuclease Cas9 cleaves its target DNA and is a powerful genome-editing tool. However, the widely used Streptococcus pyogenes Cas9 enzyme (SpCas9) requires an NGG protospacer adjacent motif (PAM) for target recognition, thereby restricting the targetable genomic loci. Here, we report a rationally engineered SpCas9 variant (SpCas9-NG) that can recognize relaxed NG PAMs. The crystal structure revealed that the loss of the base-specific interaction with the third nucleobase is compensated by newly introduced non–base-specific interactions, thereby enabling the NG PAM recognition. We showed that SpCas9-NG induces indels at endogenous target sites bearing NG PAMs in human cells. Furthermore, we found that the fusion of SpCas9-NG and the activation-induced cytidine deaminase (AID) mediates the C-to-T conversion at target sites with NG PAMs in human cells.

Fast and global detection of periodic sequence repeats in large genomic resources

Abstract Periodically repeating DNA and protein elements are involved in various important biological events including genomic evolution, gene regulation, protein complex formation, and immunity. Notably, the currently used genome editing tools such as ZFNs, TALENs, and CRISPRs are also all associated with periodically repeating biomolecules of natural organisms. Despite the biological importance of periodically repeating sequences and the expectation that new genome editing modules could be discovered from such periodical repeats, no software that globally detects such structured elements in large genomic resources in a high-throughput and unsupervised manner has been developed. We developed new software, SPADE (Search for Patterned DNA Elements), that exhaustively explores periodic DNA and protein repeats from large-scale genomic datasets based on k-mer periodicity evaluation. With a simple constraint, sequence periodicity, SPADE captured reported genome-editing-associated sequences and other protein families involving repeating domains such as tetratricopeptide, ankyrin and WD40 repeats with better performance than the other software designed for limited sets of repetitive biomolecular sequences, suggesting the high potential of this software to contribute to the discovery of new biological events and new genome editing modules.