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Oxidative stress caused by chemicals brings about mass mortalities in aquatic organisms and in this context, antioxidants and heat shock protein 70 (Hsp70) stimulating compounds represent potential alternatives to alleviate this problem during aquaculture. The antioxidant capacity and efficacies of five Malaysian indigenous microalgae, namely Auxenochlorella pyrenoidosa, Chlorella vulgaris, Messastrum gracile, Desmodesmus subspicatus and Parachlorella kessleri to regulate Hsp70 expression in the brine shrimp Artemia, an important live food species, were examined. A. pyrenoidosa contained the highest total phenol and flavonoid content (48.3 mg GAE/g extract and 34.7 mg QE/g) across all the microalgae examined in this study, whereas the lowest occurred with C. vulgaris (24.4 mg GAE/g extract and 14.0 mg QE/g). The ferric reducing antioxidant power of A. pyrenoidosa, C. vulgaris, M. gracile, D. subspicatus and P. kessleri respectively stood at 0.78, 0.62, 1.01, 0.77 and 0.68 ferrous equivalents (mM), with trolox equivalent antioxidant capacity assay revealed that A. pyrenoidosa possessed the highest scavenging activity at 1 mg/mL concentration. Interestingly, application of 1.0–2.0 × 106 cells/mL C. vulgaris, M. gracile, D. subspicatus, and P. kessleri as feed enhanced Hsp70 accumulation in Artemia, indicating that these microalgae consist stimulating compound(s) which potentially promote the synthesis of the 70-kDa stress protein in this crustacean species. Taken together, results from this study revealed that microalgae possess various antioxidant properties and coupled with their abilities to induce Hsp70, they are potential oxidative stress control alternatives in Artemia and perhaps other aquatic organisms used in aquaculture.

Recent heavy-ion collision experiments reported a surprisingly short lifetime for the hypertriton, which has been recognized as the hypertriton lifetime puzzle. Our J-PARC E73 experiment contributes to solve this puzzle with an independent experimental method by employing 3He(K−, π0) 3ΛH reaction. In this contribution, we will demonstrate our capability to provide 3ΛH binding energy information by deriving the production cross section ratio, σ3ΛH/σ4ΛH. The production cross section data for 3ΛH and 4ΛH are already available as the pilot run of E73 experiment and data analysis is in progress.

Abstract Background Plant mitochondria contain a relatively large amount of genetic information, suggesting that their functional regulation may not be as straightforward as that of metazoans. We used a genomic tiling array to draw a transcriptomic atlas of Oryza sativa japonica (rice) mitochondria, which was predicted to be approximately 490-kb long. Results Whereas statistical analysis verified the transcription of all previously known functional genes such as the ones related to oxidative phosphorylation, a similar extent of RNA expression was frequently observed in the inter-genic regions where none of the previously annotated genes are located. The newly identified open reading frames (ORFs) predicted in these transcribed inter-genic regions were generally not conserved among flowering plant species, suggesting that these ORFs did not play a role in mitochondrial principal functions. We also identified two partial fragments of retrotransposon sequences as being transcribed in rice mitochondria. Conclusion The present study indicated the previously unexpected complexity of plant mitochondrial RNA metabolism. Our transcriptomic data (Oryza sativa Mitochondrial rna Expression Server: OsMES) is publicly accessible at [http://bioinf.mind.meiji.ac.jp/cgi-bin/gbrowse/OsMes/#search].

Abstract In many eukaryotes, histone gene expression is regulated in a cell cycle-dependent manner, with a spike pattern at S phase. In fission yeast the GATA-type transcription factor Ams2 is required for transcriptional activation of all the core histone genes during S phase and Ams2 protein levels per se show concomitant periodic patterns. We have recently unveiled the molecular mechanisms underlying Ams2 fluctuation during the cell cycle. We have found that Ams2 stability varies during the cell cycle, and that the ubiquitin-proteasome pathway is responsible for Ams2 instability. Intriguingly, Ams2 proteolysis requires Hsk1-a Cdc7 homologue in fission yeast generally called Dbf4-dependent protein kinase (DDK)-and the SCF ubiquitin ligase containing the substrate receptor Pof3 F-box protein. Here, we discuss why histone synthesis has to occur only during S phase. Our results indicate that excess synthesis of core histones outside S phase results in deleterious effects on cell survival. In particular, functions of the centromere, in which the centromere-specific H3 variant CENP-A usually form centromeric nucleosomes, are greatly compromised. This defect is, at least in part, ascribable to abnormal incorporation of canonical histone H3 into these nucleosomes. Finally, we address the significance and potential implications of our work from an evolutionary point of view.

Abstract Background 13-Methyltetradecanoic acid (13-MTD), an iso-C15 branched- chain saturated fatty acid, has been shown to induce apoptotic cell death of numerous human cancer cells. However, the mechanism for the induction of apoptosis has not been fully understood. This study described the incorporation of 13-MTD into cellular lipid of SKBR-3 breast cancer cells and apoptosis related event to gain more insight into the mechanism action of this fatty acid. Results Treatment of SKBR-3 cells with 13-MTD lowered the cell viability and induced apoptosis. Proportion of 13-MTD in the glycerolipids increased to saturation level within 6 hours. Triacylglycerol contained 13-MTD in higher concentration than phospholipid with positional preference to sn-2. 13-MTD caused no changes in the caspase activity and its gene expression. Furthermore, addition of caspase-inhibitor to culture medium did not prevent the cells from the cytotoxicity of 13-MTD. No-increase in the cellular calcium level was also noted with 13-MTD treatment. However, 13-MTD disrupted the mitochondrial integrity in 4 hours, and increased the nuclear translocation of apoptosis inducing factor. Conclusion These results showed that 13-MTD disrupted the mitochondrial integrity, and induced apoptosis via caspase-independent death pathway.

Ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) techniques were evaluated and compared with conventional extraction for obtaining spent coffee ground oil (SCGO). The use of absolute ethanol (ET0) and hydrated ethanol (ET6) as solvents, two levels of SCG mass ratio:solvent, 1:4 (U4) and 1:15 (U15), and ultrasound powers of 0, 200, 400, and 600 W were tested. ET0 and U15 resulted in higher extraction yields of SCGO (Y SCGO , 82%). A positive effect of sonication on Y SCGO was observed only for condition U4. UAE resulted in defatted solids (DS) with higher apparent density values, corroborating the increase in the amount of smaller diameter particles due to sonication. The micrographs showed changes in the surfaces of the solids from the UAE and PLE, although the crystalline structures of the DS were not altered. UAE and PLE, compared to conventional extraction, did not allow significant gains in terms of Y SCGO and, consequently, in the number of contact stages in an extractor configured in cross-currents.