Obtaining and Study of Callus and Suspension Plant Cell Cultures of <Emphasis Type="Italic">Tribulus terrestris</Emphasis> L., a Producer of Steroidal Glycosides

Callus and suspension plant cell cultures of Tribulus terrestris L., a valuable medicinal plant producing steroidal glycosides, were obtained. The seeds from an American population of T. terrestris were used as explants. Regulation of the production and growth of cell cultures, as well as the biosynthetic characteristics of the cell lines, were studied. The combination of phytohormones of 2,4-D (2.0 mg/L) and BAP (1.0 mg/L) was found to be optimal for callus induction and cultivation. Suspension cell culture obtained in liquid medium of the same composition showed such high growth characteristics during prolonged cultivation (more than 2 years) as a maximum accumulation of dry biomass of 13 g/L, specific growth rate at exponential phase of 0.24 day^–1, and economical coefficient of 0.39. A semicontinuous mode of cultivation was used to grow the plant cell suspension in a lab-scale bioreactor. Screening of the steroidal glycosides in the obtained cell cultures was carried out. Steroidal glycosides were not found in the callus cultures. However, as was demonstrated by TLC and UPLC ESI MS methods, the suspension culture contained furostanol glycosides, and their amount increased during the cultivation process. These results support the hypothesis of the autoselection of cultivated cells containing compounds promoting their proliferation in vitro.     

Description of three microsatellite loci of the Baikal omul <Emphasis Type="Italic">Coregonus migratorius</Emphasis> (Georgi)

Three new microsatellite loci found for the Baikal omul Coregonus migratorius (Georgi) are described.     

Activators of protein kinase A and Epac proteins enhance the contractile response of the isolated snail (Helix pomatia) Heart to serotonin

The mechanisms of cAMP action on the contractility of the isolated heart were studied in the snail Helix pomatia. Serotonin is a powerful activator of heart contractility in this animal. Preincubation of the isolated heart ventricle with the activator of protein kinase A (PKA) Sp-8-bromoadenosine-3′,5′-cyclic monophosphothioate (200 μM) or the activator of Epac proteins 8-(4-chlorophenylthio)-2′-O-methyladenosine-3′,5′-cyclic monophosphate (100 μM) proved to enhance the amplitude of contractions induced by serotonin. Two types of changes in the contractile response were observed: each agent caused either a uniform increase in the amplitude of heart contractions at all concentrations of serotonin or an abrupt increase in the response to the first minimum dose of serotonin. These results indicate that Epac proteins along with PKA are involved in the transmission of cAMP effect on heart contractility.     

Hydrolysis of chitosan sulfate by an enzyme complex from Streptomyces kurssanovii

The possibility of enzymatic hydrolysis of chitosan was shown. The optimum conditions for the process are: sodium acetate buffer pH 6.0, 37 degrees C, 24 h, and the chitosan sulfate-protein volume ratio of 500:1 in the enzyme preparation. During hydrolysis, the intrinsic viscosity of chitosan sulfate solution decreased by a factor of 2.7.     

Ecdysteroids in stress responsive and nonresponsive Drosophila virilis lines under stress conditions

After exposure to thermal stress or a control temperature, the relative abundance of ecdysone (E) and 20-hydroxyecdysone (20E) was measured in a wild-type line of Drosophila virilis (101) that is stress responsive and in a mutant line (147) that is not stress responsive. In line 101, the 20E content was higher and E content lower in females than in males. The abundance of E and 20E in females of line 147 was significantly higher than that in females of line 101. Females of line 101 were found to respond to 60 min of heat stress (38 degrees C) by an increase in the abundance of both E and 20E, while in males of this line the amount of 20E increased and that of E declined. A role of the ecdysteroids in the control of reproduction of D. virilis under stress is discussed.     

Cell biology and life cycle of the testate amoeba Corythion delamarei

Corythion delamarei Bonnet, Thomas, 1960, a typical testate amoeba with hyaline, filiform pseudopodia (Filosea Leidy, 1879), is a mass and widely spread species in the forest soil of Leningrad district. This species has been studied in natural and experimental conditions by means of morphological, cytochemical and morphometrical methods, including original culturing in vitro. The complex life cycle of C. delamarei involves the number of phases: trophozoites, precysts, resting cysts, copulating trophozoits, cystozygotes, cells with spores inside the shell, small amoeboid cells producing spores after germination. Different stages display structural peculiarities reflecting adaptation to exogenous environment. In C. delamarei sexual process has been first discovered. It represents a primitive form of isogamic copulation of morphologically similar trophozoites copulation and results in uninuclear cystozygote formation. The zygote nucleus is a synkaryon meiosis is zygotic, and is accomplished in two steps. Copulation occurs only between two trophozoites of one and the same species. Further zygote development includes its excystation that eventually gives rise to a trophozoite which then undergoes several metagamic divisions resulting in spore formation, thus starting a new generation of trophozoites.     

The Wavelet-Based Cluster Analysis for Temporal Gene Expression Data

A variety of high-throughput methods have made it possible to generate detailed temporal expression data for a single gene or large numbers of genes. Common methods for analysis of these large data sets can be problematic. One challenge is the comparison of temporal expression data obtained from different growth conditions where the patterns of expression may be shifted in time. We propose the use of wavelet analysis to transform the data obtained under different growth conditions to permit comparison of expression patterns from experiments that have time shifts or delays. We demonstrate this approach using detailed temporal data for a single bacterial gene obtained under 72 different growth conditions. This general strategy can be applied in the analysis of data sets of thousands of genes under different conditions.[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29]     

The molecular epidemiological aspects of hiv-infection spreading in Perm region

Retrospective analysis of HIV-infection spreading in Perm region in conjunction with the genetic characterization of viral subtypes circulated on this territory from 1988 (when 1st case of infection was detected) until 2005 was performed. Analysis of epidemic process allowed to determine three periods of its development basing on both epidemic intensity and nature of circulating HIV-1 subtypes. During 1988 - 1996 (first period), when viral population was heterogenous (simultaneous circulation of three HIV-1 subtypes) with multiple routes of transmission, the epidemic process was characterized by low intensity. High incidence of HIV-infection among injection drug users and high homogeneity of circulated HIV-1 variants (98% of isolated variants belonged to HIV-1 subtype A with low level of genetic variability) were characteristics of the second period lasted from 1997 to 2001. Decrease in HIV-infection incidence in 2002-2005 was accompanied by the increase of HIV-1 transmission through heterosexual contacts and continuation of subtype A predominance between isolates. However increase in heterogeneity of viral population during this period, which manifested as increase of env and pol genes polymorphism, was detected.     

Activation of cardiac contractivity of the edible snail H. pomatia under effect of thrombin. Study of role of cAMP

Thrombin acts on mammalian cells through specific, the so-called protease-activated receptors (PARs). The thrombin action is mediated via three out of four known types of these receptors PAR(1, 3, 4). Mammalian thrombin receptors, apart from performance of other functions, control cardiac and vascular contractility. It is not known whether receptors of such kind exist in invertebrate animals. In the present work we have showed for the first time that thrombin in the concentration range of 0.01-1 units/ml increases amplitude of contractions of the isolated heart ventricle of the edible snail Helix pomatia. Its effect is reproduced by peptide ligands of receptors PAR1 and PAR4 that have sequences Ser-Phe-Leu-Leu-Arg-Asn (SFLLRN) and Glu-Tyr-Pro-Gly-Lys-Phe (QYPGKF), respectively. A potent activati of cardiac contractivity of H. pomatia is serotonin. A comparative study of mechanisms of action of serotonin and thrombin on the edible snail heart was carried out. cAMP participates in transduction of signal from serotonin receptors. On the membrane preparation from the H. pomatia heart, it was shown that thrombin and peptide ligands PAR(1, 4), unlike serotonin, did not increase adenylyl cyclase activity. Thus, mechanism of activation of cardiac contractivity of H. pomatia by thrombin differs from the action mechanism of serotonin. It is suggested that molluscs have receptors homologous to protease activated mammalian receptors.