Aberrant Active cis-Regulatory Elements Associated with Downregulation of RET Finger Protein Overcome Chemoresistance in Glioblastoma

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Parkin stabilizes PINK1 through direct interaction

Parkinson disease (PD) is the most common movement disorder and is characterized by dopaminergic dysfunction. The majority of PD cases are sporadic; however, the discovery of genes linked to rare familial forms of the disease has provided crucial insight into the molecular mechanisms of disease pathogenesis. Multiple genes mediating familial forms of Parkinson’s disease (PD) have been identified, such as parkin (PARK2) and phosphatase and tensin homologue deleted on chromosome ten (PTEN)-induced putative kinase 1: PINK1 (PARK6). Here, we showed that Parkin directly interacts with PINK1, but did not bind to pathogenic PINK1 mutants. Parkin, but not its pathogenic mutants, stabilizes PINK1 by interfering with its degradation via the ubiquitin-mediated proteasomal pathway. In addition, the interaction between Parkin and PINK1 resulted in reciprocal reduction of their solubility. Our results indicate that Parkin regulates PINK1 stabilization via direct interaction with PINK1, and operates through a common pathway with PINK1 in the pathogenesis of early-onset PD.     

Binding and transport of SFPQ-RNA granules by KIF5A/KLC1 motors promotes axon survival

Complex neural circuitry requires stable connections formed by lengthy axons. To maintain these functional circuits, fast transport delivers RNAs to distal axons where they undergo local translation. However, the mechanism that enables long-distance transport of RNA granules is not yet understood. Here, we demonstrate that a complex containing RNA and the RNA-binding protein (RBP) SFPQ interacts selectively with a tetrameric kinesin containing the adaptor KLC1 and the motor KIF5A. We show that the binding of SFPQ to the KIF5A/KLC1 motor complex is required for axon survival and is impacted by KIF5A mutations that cause Charcot-Marie Tooth (CMT) disease. Moreover, therapeutic approaches that bypass the need for local translation of SFPQ-bound proteins prevent axon degeneration in CMT models. Collectively, these observations indicate that KIF5A-mediated SFPQ-RNA granule transport may be a key function disrupted in KIF5A-linked neurologic diseases and that replacing axonally translated proteins serves as a therapeutic approach to axonal degenerative disorders.     

Secretory and continuous expression of Aspergillus niger glucose oxidase gene in Pichia pastoris

We proposed a yeast transformant cell incorporating the Aspergillus niger glucose oxidase gene (GOX gene), which is capable of constitutively as well as secretory expression. The GOX gene has been cloned in this study. This conclusion is based on the following: first, the ligated DNA determined by electrophoresis, was a 1489-1882bp fragment, close to the size of glucose oxidase (GOD), which is 1818bp. Secondly, the single open reading frame encoded a protein of 605 amino acids. Thirdly, secreted GOD recombinant proteins in the culture supernatants of the GOX gene transformant migrated as a single band in SDS-PAGE with an apparent molecular mass of between 75,000 and 100,000 Da, which is glycosylated GOD by the Pichia pastoris X-33 host machinery during the secretion process. Finally, the clones were cultured and secreted a protein, which possessed the GOD activity of catalyzing beta-d-glucose oxidation. With regard to the pH characteristics, the activity was more than 80% of the maximum activity in the range between pH 5 and pH 7. As for the temperature characteristics, the activity was not less than 92% of the maximum in the temperature range between 10 and 45 degrees C. The GOX gene transformant was able to maintain the GOD enzyme activity and produce recombinant GOD continuously for at least 2 weeks.     

Modulation of synaptic plasticity by brain estrogen in the hippocampus

The hippocampus is a center for learning and memory as well as a target of Alzheimer's disease in aged humans. Synaptic modulation by estrogen is essential to understand the molecular mechanisms of estrogen replacement therapy. Because the local synthesis of estrogen occurs in the hippocampus of both sexes, in addition to the estrogen supply from the gonads, its functions are attracting much attention.     

Color discrimination in wild boars

Two experiments were carried out in order to clarify the color perception of Japanese wild boarsSus scrofa leucomystax. Two females were trained using an operant conditioning technique to press a switch under a positive stimulus color card in order to receive food as a reward. In Exp. 1, they were tested for discrimination between 3 colors (red, green and blue) and gray. The luminosity of all colors was the same. The wild boars succeeded in discrimination tests between blue and gray, but failed to discriminate red from gray. They also did not discriminate green from gray so clearly as blue from gray. In Exp. 2, the same wild boars were tested to discriminate between 8 kinds of color, which were created by gradating green yellow into red purple except for the 3 colors used in Exp. 1, and gray. They could clearly discriminate blue, purple blue and a part of purple from gray. In these experiments, wild boars were capable of recognizing bluish colors. However, for colors approaching green or yellow, they failed the test by degrees.     

Toll-like Receptors as a Target of Food-derived Anti-inflammatory Compounds

Toll-like receptors (TLRs) play a key role in linking pathogen recognition with the induction of innate immunity. They have been implicated in the pathogenesis of chronic inflammatory diseases, representing potential targets for prevention/treatment. Vegetable-rich diets are associated with the reduced risk of several inflammatory disorders. In the present study, based on an extensive screening of vegetable extracts for TLR-inhibiting activity in HEK293 cells co-expressing TLR with the NF-κB reporter gene, we found cabbage and onion extracts to be the richest sources of a TLR signaling inhibitor. To identify the active substances, we performed activity-guiding separation of the principal inhibitors and identified 3-methylsulfinylpropyl isothiocyanate (iberin) from the cabbage and quercetin and quercetin 4′-O-β-glucoside from the onion, among which iberin showed the most potent inhibitory effect. It was revealed that iberin specifically acted on the dimerization step of TLRs in the TLR signaling pathway. To gain insight into the inhibitory mechanism of TLR dimerization, we developed a novel probe combining an isothiocyanate-reactive group and an alkyne functionality for click chemistry and detected the probe bound to the TLRs in living cells, suggesting that iberin disrupts dimerization of the TLRs via covalent binding. Furthermore, we designed a variety of iberin analogues and found that the inhibition potency was influenced by the oxidation state of the sulfur. Modeling studies of the iberin analogues showed that the oxidation state of sulfur might influence the global shape of the isothiocyanates. These findings establish the TLR dimerization step as a target of food-derived anti-inflammatory compounds.     

Mitogenomic phylogeny of the Percichthyidae and Centrarchiformes (Percomorphaceae): comparison with recent nuclear gene-based studies and simultaneous analysis

Delineation of the fish family Percichthyidae (Percomorphaceae) has a long and convoluted history, with recent morphological-based studies restricting species members to South American and Australian freshwater and catadromous temperate perches. Four recent nuclear gene-based phylogenetic studies, however, found that the Percichthyidae was not monophyletic and was nested within a newly discovered inter-familial clade of Percomorphaceae, the Centrarchiformes, which comprises the Centrarchidae and 12 other families. Here, we reexamined the systematics of the Percichthyidae and Centrarchiformes based on new mitogenomic information. Our mitogenomic results are globally congruent with the recent nuclear gene-based studies although the overall amount of phylogenetic signal of the mitogenome is lower. They do not support the monophyly of the Percichthyidae, because the catadromous genus Percalates is not exclusively related to the freshwater percichthyids. The Percichthyidae (minus Percalates) and Percalates belong to a larger clade, equivalent to the Centrarchiformes, but their respective sister groups are unresolved. Because all recent analyses recover a monophyletic Centrarchiformes but with substantially different intra-relationships, we performed a simultaneous analysis for a character set combining the mitogenome and 19 nuclear genes previously published, for 22 centrarchiform taxa. This analysis furthermore indicates that the Centrarchiformes are divided into three lineages and the superfamily Cirrhitoidea is monophyletic as well as the temperate and freshwater centrarchiform perch-like fishes. It also clarifies some of the relationships within the freshwater Percichthyidae.