Identification of genetically modified vegetable sources in food and feed using hydrogel oligonucleotide microchip

A method of multiplex polymerase chain reaction (PCR) followed by the hybridization on a hydrogel oligonucleotide biochip was developed for simultaneous identification of ten different transgenic elements of plant DNA in feed and food products. The biochip contained 22 immobilized probes intended for (i) detection of plant DNA; (ii) plant species determination (soybean, maize, potato, rice); (iii) identification of transgenic elements, including 35S CaMV, 35S FMV, rice actine gene promoters, nos, 35S CaMV, ocs, pea rbcS1 gene terminators, and bar, gus, nptII marker genes. The limit of detection was 0.5% of genetically modified (GM) soybean and maize in analyzed samples. Identification of transgenic DNA in food and feed products using either the developed approach or real-time PCR led to virtually identical results. The assay can be used for selection of GM samples by screening food and feed products for subsequent quantitative determination of the GM component based on the identified transgene.     

Identification of plant-derived genetically modified organisms in food and feed using a hydrogel oligonucleotide microchip

A method of multiplex polymerase chain reaction (PCR) followed by hybridization on a hydrogel oligonucleotide biochip was developed for simultaneous identification of ten different transgenic elements of plant DNA in food and feed products. The biochip contained 22 immobilized oligonucleotide probes that were intended for (1) detection of plant DNA, (2) determination of plant species (soybean, maize, potato, and rice), and (3) identification of transgenic elements, including sequences of 35S CaMV, 35S FMV, rice actin gene promoters, nos, 35S CaMV, ocs, pea rbcS1 gene terminators, and bar, gus, and nptII marker genes. The limit of detection was 0.5% for genetically modified (GM) soybean and maize in the analyzed samples. The tests on food and feed products using the developed approach and real-time PCR showed full agreement in determination of transgenic DNA in the samples. The proposed assay can be used for selection of GM samples by screening food and feed products for subsequent quantitative determination of GM component based on the identified transgene.     

Stellate cells of aortic intima: II. Arborization of intimal cells in culture.

The present study analyzed effects of different cAMP-elevators on cell morphology in primary culture of human intimal and medial cells from grossly normal and atherosclerotic areas. In primary culture of human aortic cells adenylate cyclase activator forskolin and other cAMP elevators induced arborization of cells, i.e. they reversibly changed the shape of cells. This resulted in the formation of thin branching processes and in the concentration of cytoplasm around the nucleus. In the culture, the shape of the arborized cells resembled that of stellate ones detected in the aortic intima in situ. The arborization of cells was accompanied by destruction of myofilaments. Due to cAMP elevators' effect, most of the arborized cells were exhibited in the cultures isolated from the elastic-hyperplastic layer of the intima. The number of arborized cells was significantly less in the cultures isolated from the musculo-elastic layer and still lesser in those isolated from media. We failed to reveal any significant difference in the number of arborized cells cultured from fatty streaks, atherosclerotic plaques and grossly normal aortic areas. Obtained results suggest that the previously revealed polymorphism of human aortic intimal cells may be accounted for by the cell shape transformations underlined by the mechanism similar to that of arborization in vitro.     

The Seventeenth International Conference on Plant Growth Substances (Brno,Czech Republic,July 1–6, 2001)

Russian Journal of Plant Physiology -     

Centric diatoms (Centrophyceae,Bacillariophyta) in watercourses and bodies of water in southeast of West Siberian Plain and Polar Ural

The study of phytoplankton from rivers and lakes in the southeastern part of the West Siberian Plain and the eastern macrosclope of the Polar Ural by scanning electron microscopy has revealed 25 taxa of Bacillariophyta from the class Centrophyceae (seven Aulacoseira, one Cyclostephanos, four Cyclotella, two Discostella, one Melosira, one Puncticulata, seven Stephanodiscus, and two Thalassiosira), including new species for the flora of the investigated bodies of water. The revision of the species composition of Centrophyceae in bodies of water and watercourses in the southeast part of the West Siberian Plain has allowed more exact identifying the taxonomic spectrum of this class. At present, the list includes 55 species, varieties and forms. During first studies conducted in rivers and lakes of the Lyapin River basin (Polar Ural) 16 species of centric diatoms that belong to the genera Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Puncticulata, and Stephanodiscus have been recorded.     

Effect of a chalone-containing preparation from Ehrlich ascites tumor on DNA synthesis and cell division in the tumor in relation to the time of day

The mitosis inhibitory action of chalone-containing preparation of the Ehrlich ascite tumour was shown to depend on the time of its administration on round the clock, and on the circadian rhythm phase of the mitotic activity in this tumour. This allowed a conclusion that the chalone system of the tumour may be involved in the formation of the circadian rhythm of cell division. It was found that Ehrlich's ascite tumour chalone system regulated DNA synthesis influencing the cell passage from G1-phase of the mitotic cycle to S-phase, and the processes occurring during S-phase.     

Morphological and ecological differentiation of sympatric whitefish species of the genus <Emphasis Type="Italic">Coregonus</Emphasis> from Lake Taymyr

Results of the morphological analysis of ecology and feeding of two sympatric forms of whitefishes (lacustrine and lacustrine–riverine) inhabiting Lake Taymyr (the Taymyr Peninsula) are presented in the article. It is revealed that these forms do not differ in the number of gill rakers on the first branchial arch and in the number of perforated scales in the lateral line, but they do differ in plastic characters, spawning periods, and area. At the age of 2–3 years they become separate in regards to feeding type. It is assumed that both forms of whitefishes inhabited Lake Taymyr simultaneously with the filling of the lake basin. Apparently the taxonomic status of the sympatric whitefishes from Lake Taymyr is broader than the term “ecological form.”     

Phasing out the bad—How SQSTM1/p62 sequesters ubiquitinated proteins for degradation by autophagy

The degradation of misfolded, ubiquitinated proteins is essential for cellular homeostasis. These proteins are primarily degraded by the ubiquitin-proteasome system (UPS) and macroautophagy/autophagy serves as a backup mechanism when the UPS is overloaded. How autophagy and the UPS are coordinated is not fully understood. During the autophagy of misfolded, ubiquitinated proteins, referred to as aggrephagy, substrate proteins are clustered into larger structures in a SQSTM1/p62-dependent manner before they are sequestered by phagophores, the precursors to autophagosomes. We have recently shown that SQSTM1/p62 and ubiquitinated proteins spontaneously phase separate into micrometer-sized clusters in vitro. This enabled us to characterize the properties of the ubiquitin-positive substrates that are necessary for the SQSTM1/p62-mediated cluster formation. Our results suggest that aggrephagy is triggered by the accumulation of substrates with multiple ubiquitin chains and that the process can be inhibited by active proteasomes.     

Anatomy, physiology and biochemistry of root nodules of Sprint-2 Fix-, a symbiotically defective mutant of pea (Pisum sativum L.)

A plant-determined pea mutant Sprint-2 Fix^– and the parentalline Sprint-2 were compared for selected physiological and biochemicalparameters. The Fix^– mutation prevented differentiationof Rhizobium leguminosarum bacteria into bacteroids and producedlarge, white, non-fixing nodules. These lacked nitrogenase-linkedrespiration, but had a background rate of CO₂ evolution similarto the normal Fix⁺ nodules. The cortical structure of the ineffectivenodules suggests the existence of an oxygen diffusion barrierand this was supported by a low oxygen concentration in thecentral region (0.5–3.0%), measured using an O₂ sensitivemicro-electrode. Sucrose and starch contents were similar innormal and ineffective nodules while ononitol content was about15 times lower in the Fix^– nodules. The distribution ofstarch was also different in the two nodule types. The activitiesof glutamine synthetase (GS), sucrose synthase (SS), phosphoenolpyruvatecarboxylase (PEPC) and alanine pyruvate aminotransferase (APAT)were markedly higher in Fix⁺ nodules while the activities ofpyruvate decarboxylase (PDC), alcohol dehydrogenase (ADH) andglutamate dehydrogenase (GDH) were higher in Fix^– nodules.The data from immunodetection of host nodule proteins confirmedthe reduced levels of sucrose synthase and the almost completeabsence of glutamine synthetase and leghaemoglobin in mutantnodules. There was no significant difference in the amount ofnitrogenase component 1 extracted from the microsymbiont ofnormal and ineffective nodules, but component 2 was hardly detectablein the Fix^– mutant. Key words: Pisum sativum, Fix^– mutant, nodules