REEXAMINATION OF PHYLOGENETIC RELATIONSHIPS WITHIN THE COLONIAL VOLVOCALES (CHLOROPHYTA): AN ANALYSIS OF atpB AND rbcL GENE SEQUENCES

The chloroplast-encoded atp B gene was sequenced from 33 strains representing 28 species of the colonial Volvocales (the Volvocaceae and its relatives) to reexamine phylogenetic relationships as previously deduced by morphological data and rbc L gene sequence data.1128 base pairs in the coding regions of the atp B gene were analyzed by MP, NJ, and ML analyses. Although supported with relatively low bootstrap values (75% and 65% in the NJ and ML analyses, respectively), three anisogamous/oogamous volvocacean genera— Eudorina, Pleodorina, and Volvox, excluding the section Volvox (= Euvolvox, illegitimate name), constituted a large monophyletic group (Eudorina group). Outside the Eudorina group, a robust lineage composed of three species of Volvox sect. Volvox was resolved as in the rbc L gene trees, rejecting the hypothesis of the previous cladistic analysis based on morphological data that the genus Volvox is monophyletic. In addition, the NJ and ML trees suggested that Eudorina is a nonmonophyletic genus as inferred from the morphological data and rbc L gene sequences. Although phylogenetic status of the genus Gonium is ambiguous in the rbc L gene trees and the paraphyly of this genus is resolved in the cladistic analysis based on morphological data, the atp B gene sequence data suggest monophyly of Gonium with relatively low bootstrap values (56–61%) in the NJ and ML trees. On the basis of the combined sequence data (2256 base pairs) from atp B and rbc L genes, Gonium was resolved as a robust monophyletic genus in the NJ and ML trees (with 68–86% bootstrap values), and Eudorina elegans Ehrenberg represented a paraphyletic species positioned most basally within the Eudorina group. However, phylogenetic status and relationships of the families of the colonial Volvocales were still almost ambiguous even in the combined analysis.     

Ribosome induces transdifferentiation of A549 and H-111-TC cancer cell lines

Previously we reported that, lactic acid bacteria (LAB) can induce human dermal fibroblast (HDF) cells to form multipotent cell clusters which are able to transdifferentiate into three germ layer derived cell lineages. Later on, we confirmed that ribosome is responsible for the LAB-induced transdifferentiation and ribosomes from diverse organisms can mimic the LAB effect on HDF cells. In our present study we have shown that, upon incorporation of ribosomes, non-small cell lung cancer cell line A549 and gastric tubular adenocarcinoma cell line H-111-TC are transformed into spheroid like morphology those can be transdifferentiated into adipocytes and osteoblast. Our qPCR analysis has revealed that, during the formation of ribosome induced cancer cell spheroids, the expression of the cancer cell associated markers and cell cycle/proliferation markers were altered at different time point. Through our investigation, here we report a novel and a non-invasive approach for cancer cell reprogramming by incorporating ribosomes.     

Structure and organization of the mitochondrial genome of the unicellular red alga Cyanidioschyzon merolae deduced from the complete nucleotide sequence.

The complete nucleotide sequence of the mitochondrial genome of a very primitive unicellular red alga, Cyanidioschyzon merolae , has been determined. The mitochondrial genome of C.merolae contains 34 genes for proteins including unidentified open reading frames (ORFs) (three subunits of cytochrome c oxidase, apocytochrome b protein, three subunits of F1F0-ATPase, seven subunits of NADH ubiquinone oxidoreductase, three subunits of succinate dehydrogenase, four proteins implicated in c-type cytochrome biogenesis, 11 ribosomal subunits and two unidentified open reading frames), three genes for rRNAs and 25 genes for tRNAs. The G+C content of this mitochondrial genome is 27.2%. The genes are encoded on both strands. The genome size is comparatively small for a plant mitochondrial genome (32 211 bp). The mitochondrial genome resembles those of plants in its gene content because it contains several ribosomal protein genes and ORFs shared by other plant mitochondrial genomes. In contrast, it resembles those of animals in the genome organization, because it has very short intergenic regions and no introns. The gene set in this mitochondrial genome is a subset of that of Reclinomonas americana , an amoeboid protozoan. The results suggest that plant mitochondria originate from the same ancestor as other mitochondria and that most genes were lost from the mitochondrial genome at a fairly early stage of the evolution of the plants.     

LSD1 Overexpression Is Associated with Poor Prognosis in Basal-Like Breast Cancer,and Sensitivity to PARP Inhibition

LSD1, a lysine-specific histone demethylase, is overexpressed in several types of cancers and linked to poor outcomes. In breast cancer, the significance of LSD1 overexpression is not clear. We have performed an in silico analysis to assess the relationship of LSD1 expression to clinical outcome. We demonstrate that LSD1 overexpression is a poor prognostic factor in breast cancer, especially in basal-like breast cancer, a subtype of breast cancer with aggressive clinical features. This link is also observed in samples of triple negative breast cancer. Interestingly, we note that overexpression of LSD1 correlates with down-regulation of BRCA1 in triple negative breast cancer. This phenomenon is also observed in in vitro models of basal-like breast cancer, and is associated with an increased sensitivity to PARP inhibitors. We propose therefore that high expression levels of the demethylase LSD1 is a potential prognostic factor of poor outcome in basal-like breast cancer, and that PARP inhibition may be a therapeutic strategy of interest in this poor prognostic subtype with overexpression of LSD1.     

Increase in tissue cysteine level and excretion of sulfate and taurine after intragastric administration ofl-2-oxothiazolidine-4-carboxylate in rats

Summary Five mmol ofl-2-oxothiazolidine-4-carboxylate (OTC)/kg of body weight was administered into the stomach of rats, and cysteine levels in tissues and sulfate and taurine excreted in the urine were determined. The cysteine (plus cystine expressed as cysteine) concentration in the liver increased to 170–200% of the original level at 30 min and that in the blood to 160% at 60 min after the OTC administration. These high levels were maintained until 8 h after the administration and decreased gradually thereafter. Excretion of sulfate and taurine increased after the OTC administration and the increase corresponded to 26% and 15%, respectively, of the OTC administered. These findings suggest that at least about 40% of the OTC administered into the stomach was taken up and converted to cysteine, which was metabolized to sulfate and taurine.     

Overexpression of glutathione peroxidase attenuates myocardial remodeling and preserves diastolic function in diabetic heart

Oxidative stress plays an important role in the structural and functional abnormalities of diabetic heart. Glutathione peroxidase (GSHPx) is a critical antioxidant enzyme that removes H(2)O(2) in both the cytosol and mitochondia. We hypothesized that the overexpression of GSHPx gene could attenuate left ventricular (LV) remodeling in diabetes mellitus (DM). We induced DM by injection of streptozotocin (160 mg/kg ip) in male GSHPx transgenic mice (TG+DM) and nontransgenic wildtype littermates (WT+DM). GSHPx activity was higher in the hearts of TG mice compared with WT mice, with no significant changes in other antioxidant enzymes. LV thiobarbituric acid-reactive substances measured in TG+DM at 8 wk were significantly lower than those in WT+DM (58 +/- 3 vs. 71 +/- 5 nmol/g, P < 0.05). Heart rate and aortic blood pressure were comparable between groups. Systolic function was preserved normal in WT+DM and TG+DM mice. In contrast, diastolic function was impaired in WT+DM and was improved in TG+DM as assessed by the deceleration time of peak velocity of transmitral diastolic flow and the time needed for relaxation of 50% maximal LV pressure to baseline value (tau; 13.5 +/- 1.2 vs. 8.9 +/- 0.7 ms, P < 0.01). The TG+DM values were comparable with those of WT+Control (tau; 7.8 +/- 0.2 ms). Improvement of LV diastolic function was accompanied by the attenuation of myocyte hypertrophy, interstitial fibrosis, and apoptosis. Overexpression of GSHPx gene ameliorated LV remodeling and diastolic dysfunction in DM. Therapies designed to interfere with oxidative stress might be beneficial to prevent cardiac abnormalities in DM.     

Thyroid hormonal activity of the flame retardants tetrabromobisphenol A and tetrachlorobisphenol A

The thyroid hormonal-disrupting activity of the flame retardants tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA) was examined and compared with that of bisphenol A, a typical estrogenic xenobiotic. TBBPA and TCBPA, halogenated derivatives of bisphenol A, markedly inhibited the binding of triiodothyronine (T(3); 1 x 10(-10) M) to thyroid hormone receptor in the concentration range of 1 x 10(-6) to 1 x 10(-4) M, but bisphenol A did not. The thyroid hormonal activity of TBBPA and TCBPA was also examined using rat pituitary cell line GH3 cells, which grow and release growth hormone (GH) depending on thyroid hormone. TBBPA and TCBPA enhanced the proliferation of GH3 cells and stimulated their production of GH in the concentration range of 1 x 10(-6) to 1 x 10(-4) M, while bisphenol A was inactive. TBBPA, TCBPA, and bisphenol A did not show antagonistic action, i.e., these compounds did not inhibit the hormonal activity of T(3) to induce growth and GH production of GH3 cells. TBBPA and TCBPA, as well as bisphenol A, enhanced the proliferation of MtT/E-2 cells, whose growth is estrogen-dependent. These results suggest that TBBPA and TCBPA act as thyroid hormone agonists, as well as estrogens.     

Monoclonal antibodies that depress a specific subset of multiple components of the glutathione-induced response ofHydra

Summary Reduced glutathione evokes a feeding response, the tentacle-ball formation inHydra japonica. This response consists of at least 5 components (R1–R5). We raised 6 monoclonal antibodies (mAbs), each of which depressed a specific subset of these components, and we also examined the immunocytochemical localization of antigens with these mAbs at light microscopic level. The 2 mAbs that depressed R2 and R4 bound to the cnidocils of the desmoneme and the stenotele nematocytes; the 3 mAbs that depressed R5 bound to the apical surface adjacent to the cnidocils of the nematocytes; and the 2 mAbs that depressed R1 and R3 bound to the apical spot structures of unidentified cells in the ectoderm.Together with the specificity of the action of the mAbs on the behavioral response, the correspondence between the effects on the response and the structures visualized with these mAbs suggests that these structures include components of the receptor-effector system relevant to chemoreception.