Prp19/Pso4 Is an Autoinhibited Ubiquitin Ligase Activated by Stepwise Assembly of Three Splicing Factors

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On the problem of ratio of anadromy and residence in salmonids (Salmonidae)

According to published and original data, the anadromy and residence in salmonids (Salmonidae) are considered: within one population; in males and females; in different populations in the area of one species under natural conditions; outside of the natural area, at introduction; types of anadromy and residence in different species; causes and mechanisms of formation of anadromous and resident strategies; and applied consequences in the light of notions on formation of life strategies.     

Mechanisms of epithelial sodium channel (ENaC) regulation by cortactin: Involvement of dynamin

We have recently shown that epithelial sodium channels (ENaCs) are regulated by the actin-binding protein cortactin via the Arp2/3 protein complex. It has been also demonstrated that a GTPase dynamin, which is known to regulate clathrin-mediated endocytosis, can as well initiate signaling cascades regulated by cortactin. This study was designed to investigate the involvement of dynamin into cortactin-mediated regulation of ENaC. Initially, a recently described inhibitor of dynamin, dynasore, was used. However, use of this inhibitor seemed to be inappropriate due to discovered side effects. Thus, treatment of mpkCCD_c14 cells monolayers with dynasore (in concentrations of 10 and 100 μM) resulted in a decrease in ENaC-mediated transepithelial currents. Besides, dynasore caused reduced amiloride-sensitive currents in CHO cells transfected with ENaC subunits. Therefore, the data demonstrated that dynasore down regulates both native and overexpressed channel’s activity and use of this drug is not appropriate for studies of ENaC endocytosis. We hypothesize that this effect is most likely caused either by dynasore’s toxic actions upon the cells or by enhanced endocytosis of ENaC-activating proteins. In the following experiments plasmids encoding mutant forms of dynamin and cortactin were used. Dominant negative dynamin (K44A) transfected into CHO cells together with ENaC subunits significantly increased amiloride-sensitive current density compared to cells transfected with ENaC only (control); additional transfection of cortactin together with the K44A dynamin resulted in current density restitution back to the control level. Moreover, ENaC overexpression with the SH3 domain of cortactin, which is responsible for dynamin binding, caused a decrease of ENaC current. Thus, we have shown in this study that cortactin can mediate ENaC activity not only via the Arp2/3 complex, but also through the dynamin-mediated processes.     

Comparative evaluation of the results of mono- and polychemotherapy of disseminated forms of breast cancer using the CMFVP program and anthracycline antibiotics (carminomycin and adriamycin)

A total of 203 out patients with disseminated cancer of the mammary glands subjected to chemotherapy were followed up. Of these, 44 patients were treated according to the CMFVP program, 66 were subjected to monochemotherapy with carminomycin, 42 were treated with combinations of carminomycin and dibromdulcytol, 14 patients received monochemotherapy with adriamycin and 37 polychemotherapy according to the scheme of fluorouracil + adriamycin + cyclophosphamide. In addition to the early-demonstrated efficacy of adriamycin and the Cooper scheme, the comparative estimation of the treatment programs showed that carminomycin, a new antitumor antibiotic made in the USSR, had an obvious activity when used alone or in combination with dibromdulcytol, an alkylating agent, in the treatment of primary extended forms, relapses and metastases of mammary tumors. The data indicate that wide use of carminomycin which is comparatively low toxic is advisable in the treatment of disseminated cancer of the mammary gland.     

Features of reproductive biology in two tropical fish species from the family Scorpaenidae

Composition of the urogenital system, oocyte development, gamete morphology, and features of embryonic development are described in Scorpaenopsis possi and Sebastapistes cyanostigma (Scorpaenidae) from the Nha Trang Bay, the South China Sea (Vietnam). In males of both species, paired spermiducts enter into the anterior dorsal part of the hypertrophied urinary bladder containing mature sperm. The duration of progressive movements of spermatozoa obtained from the testes and urinary bladder is 5–6 and 12–15 min after activation, respectively. Ovulated oocytes possess oval shapes, they are transparent and without oil droplets. The oocytes are embedded into the floating gelatinous matrix. Insemination of the eggs in nature is apparently external. The embryos of S. cyanostigma hatch at a more advanced morphological condition in comparison to the embryos of Sc. possi. The features of reproductive biology are discussed in the context of the evolution of viviparity within the family.     

Genetic diversity of charrs of the Commander Islands based on the analysis of mitochondrial DNA

Nucleotide sequences of the mitochondrial DNA cytochrome b (CytB) gene fragment and the control region (D-loop) of Dolly Varden (Salvelinus malma) from the Commander Islands and the Kol River of the Kamchatka Peninsula were examined. A high level of genetic variability of island populations comparable to that of the mainland population of western Kamchatka was demonstrated. The belonging of the Commander Islands chars to the genetic lineage of northern Dolly Varden Salvelinus malma malma was confirmed.     

Organ correlations inchenopodium rabrum l. shoots studied by Means of32P Distribution

21-day old plants ofChenopodium rubrum L. ecotype 374 were used. Organ relationships in the shoots were investigated by³²P distribution, which indicated different organ correlations in plants grown in continuous light and in plants treated with flower-inducing and non-inducing dark periods. Dark periods were associated with a low³²P distribution in young leaves and a high one in axillary buds. In the following light period the high³²P distribution in axillary buds continued whereas the³²P distribution in the leaves on the main axis increased and was similar to that in plants grown in continuous light. The high³²P distribution in axillary buds was brought about by both, flower-inducing and non-inducing dark treatments. Decapitation resulted in a high³²P distribution in buds, in continuous light an increased³²P distribution was also found in leaves. These effects were not fully cancelled by IAA application. The results are discussed with respect to an assumption that decrease of apical dominance represents a step in a sequence of events leading to flowering.     

Formation of fluorine technogenic anomalies in above-ground ecosystems of Siberia: Biological sorption,monitoring, possibility of lowering the negative impact

This paper studies how aluminum smelter emissions into the atmosphere affect the accumulation of fluorine by soil and plants, as well as change the chemical composition in leaves of woody plants. The ratio between total and extractable fluorine is ascertained to vary widely depending on the plant species. Meanwhile, gas resistant plants are characterized by an increased ash content in leaves (at the expense of K, P, Ca, etc.) and growth in the ratio between total and water-soluble fluorine. Plant resistance to fluorine that enters tissues depends on the capability of an organism to transform the toxicant into insoluble forms, which are not involved in physiological processes, i.e., on the presence of tissue elements with high precipitating capability. The gas-resistant species are ascertained to be characterized by high capability of limiting the intake of fluorine through roots, as well as its migration through a plant (especially to the organs that determine the further development of an organism).