MT-LOOP-dependent Localization of Membrane Type I Matrix Metalloproteinase (MT1-MMP) to the Cell Adhesion Complexes Promotes Cancer Cell Invasion

Localization of membrane type I matrix metalloproteinase (MT1-MMP) to the leading edge is thought to be a crucial step during cancer cell invasion. However, its mechanisms and functional impact on cellular invasion have not been clearly defined. In this report, we have identified the MT-LOOP, a loop region in the catalytic domain of MT1-MMP (¹⁶³PYAYIREG¹⁷⁰), as an essential region for MT1-MMP to promote cellular invasion. Deletion of the MT-LOOP effectively inhibited functions of MT1-MMP on the cell surface, including proMMP-2 activation, degradation of gelatin and collagen films, and cellular invasion into a collagen matrix. This is not due to loss of the catalytic function of MT1-MMP but due to inefficient localization of the enzyme to β1-integrin-rich cell adhesion complexes at the plasma membrane. We also found that an antibody that specifically recognizes the MT-LOOP region of MT1-MMP (LOOP_Ab) inhibited MT1-MMP functions, fully mimicking the phenotype of the MT-LOOP deletion mutant. We therefore propose that the MT-LOOP region is an interface for molecular interactions that mediate enzyme localization to cell adhesion complexes and regulate MT1-MMP functions. Our findings have revealed a novel mechanism regulating MT1-MMP during cellular invasion and have identified the MT-LOOP as a potential exosite target region to develop selective MT1-MMP inhibitors.     

Lead optimization of 5-amino-6-(2,2-dimethyl-5-oxo-4-phenylpiperazin-1-yl)-4-hydroxyhexanamides to reduce a cardiac safety issue: Discovery of DS-8108b,an orally active renin inhibitor

With the aim to address an undesired cardiac issue observed with our related compound in the recently disclosed novel series of renin inhibitors, further chemical modifications of this series were performed. Extensive structure–activity relationships studies as well as in vivo cardiac studies using the electrophysiology rat model led to the discovery of clinical candidate trans-adamantan-1-ol analogue 56 (DS-8108b) as a potent renin inhibitor with reduced potential cardiac risk. Oral administration of single doses of 3 and 10 mg/kg of 56 in cynomolgus monkeys pre-treated with furosemide led to significant reduction of mean arterial blood pressure for more than 12 h.     

Change of Freezing Resistance and Retention of Metabolic and Differentiation Potentials in Cultured Green Lavandula vera Cells Which Survived Repeated Freeze-thaw Procedures

Cryostorage is one suitable method to preserve various desired types of cells. However, all cells do not survive after storage in liquid nitrogen. This suggests the possibility that the properties of the cells which survive after the storage differ from those of the unfrozen original cells.

Therefore, we did the same freeze-thaw procedure of cultured green Lavandula vera cells over again and compared the metabolic and the differentiation potentials of the cells which survived after the repeated freeze-thaw procedures with those of the unfrozen original cells. The results we found were that the frequency of colony formation of the cells which survived after the procedures was high, but that the biosynthetic capability for biotin and the differentiation potentials such as chloroplast formation and plantlet formation of the cells were equal to those of the unfrozen original cells. Cryostorage of cells in liquid nitrogen is discussed in terms of the preservation of various desired types of cells.     

Quantification of Physical and Cyto-physiological Conditions for the Electrofusion of Saccharomyces cerevisiae

Various conditions for obtaining hybrids of the auxotrophic mutants SH1509 and SH1512 of Saccharomyces cerevisiae by electrofusion were investigated. An AC field of 400 V_p/cm and a DC field of 2 square pulses (7 kV/cm; 60/βsec each) at an interval of 0.5 sec were effective. Treatment with 0.2 (SH1509) or l.0 mg/ml (SH1512) Zymolyase for 1 or 1.5 hr was essential. As to the molarity of the osmotic stabilizer (sorbitol), the hybrid yield peaked at 0.6 m. The presence of CaCl₂ (up to 0.4 mm) or 0.1 mm CaCl₂ with 0.1 mm MgCl₂ enhanced the yield. The temperature of the spheroplast suspension during pulsations also affected the yield, the most suitable temperature being 28°C.     

Lipid Compositions of Photomixotrophic Green Calluses and Chlorophyll Deficient Leaves of Tobacco

Among photomixotrophic green calluses tested (N. rustica. N. tobacum L. cv. BY-4 and Samsun), the callus of Samsun had the highest contents of chlorophyll and chloroplast lipids, such as monogalactosyldiglyceride (MGDG), digalactosyldiglyceride (DGDG), sulfoquinovosyldigly-ceride (SQDG) and phosphatidylglycerol (PG). However, the chlorophyll and chloroplast lipids in the green callus of Samsun were still 1/6 and 1/3 of that in the parent leaves, respectively. The relative content of a-linolenate in MGDG, DGDG and SQDG of the green calluses were higher than that of the white calluses. The ratios of hexadecatrienoate in MGDG and hexadeceno-ate (Δ³-trans) in PG in the green calluses were trace or less compared with that of the parent leaves. The crude lipids and total fatty acid contents of the chlorophyll deficient leaves (N. taba-cum L. cv. Consolation 402 and Dominant Aurea Su/su) were almost the same as those of the normal leaves (cv. BY-4 and Samsun), although the chlorophyll contents of the chlorophyll deficient leaves were 1/3 ~ 1/4 of that of the normal leaves. The ratios of chloroplast lipids in the total polar lipids in the chlorophyll deficient leaves were a little lower than that in the normal green leaves, but the former had a slightly higher ratio of phospholipids such as phosphatidylcholine and phosphatidylethanolamine than the latter. There were few differences in the fatty acid compositions of each individual lipid betweeen both types of leaves.     

Brain Training Game Boosts Executive Functions,Working Memory and Processing Speed in the Young Adults: A Randomized Controlled Trial

Background

Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.

Methods

We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).

Results and Discussion

Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.

Conclusions

Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.

Trial Registration

UMIN Clinical Trial Registry 000005618.     

<Emphasis Type="Italic">Bruguiera hainesii</Emphasis>, a critically endangered mangrove species,is a hybrid between <Emphasis Type="Italic">B. cylindrica</Emphasis> and <Emphasis Type="Italic">B. gymnorhiza</Emphasis> (Rhizophoraceae)

Bruguiera hainesii (Rhizophoraceae) is one of the two Critically Endangered mangrove species listed in the IUCN Red List of Threatened Species. Although the species is vulnerable to extinction, its genetic diversity and the evolutionary relationships with other Bruguiera species are not well understood. Also, intermediate morphological characters imply that the species might be of hybrid origin. To clarify the genetic relationship between B. hainesii and other Bruguiera species, we conducted molecular analyses including all six Bruguiera species using DNA sequences of two nuclear genes (CesA and UNK) and three chloroplast regions (intergenic spacer regions of trnL-trnF, trnS-trnG and atpB-rbcL). For nuclear DNA markers, all nine B. hainesii samples from five populations were heterozygous at both loci, with one allele was shared with B. cylindrica, and the other with B. gymnorhiza. For chloroplast DNA markers, the two haplotypes found in B. hainesii were shared only by B. cylindrica. These results suggested that B. hainesii is a hybrid between B. cylindrica as the maternal parent and B. gymnorhiza as the paternal one. Furthermore, chloroplast DNA haplotypes found in B. hainesii suggest that hybridization has occurred independently in regions where the distribution ranges of the parental species meet. As the IUCN Red List of Threatened Species currently excludes hybrids (except for apomictic plant hybrids), the conservation status of B. hainesii should be reconsidered.     

Anti‐barnacle Activity of Isocyanides Derived from Amino Acids

Creation of new potent antifouling active compounds is important for the development of environmentally friendly antifouling agents. Fifteen isocyanide congeners derived from proteinogenic amino acids were synthesized, and the antifouling activity and toxicity of these compounds against cypris larvae of the barnacle Balanus amphitrite were investigated. All synthesized amino acid‐isocyanides exhibited potent anti‐barnacle activity with EC₅₀ values of 0.07 – 10.34 μg/ml after 120 h exposure without significant toxicity. In addition, seven compounds showed more than 95% settlement inhibition of the cypris larvae at 10 μg/ml after 120 h exposure without any mortality observed. Considering their structure, these amino acid‐isocyanides would eventually be biodegraded to their original nontoxic amino acids. These should be useful for further research focused on the development of environmentally friendly antifoulants.