Electron microscopic study of rapid morphogenetic processes in embryonic tissue explants of amphibia]

Submicroscopic rearrangements are described. They serve as the bases of rapid (up to 20 min) changes in the form of the common frog neurula explants: formation of filamentous layer under "naked" surface, appearance of lobopodia on "naked" surface, their "flow", cell polarization and submersion. In all these processes an active part appears to be played by microtubules and microfilaments the bundles of which are always oriented along the long axes of active cells or the directions of passive mechanical tensions. In the cells which are not yet polarized the microtubules form under the surface adjacent to the already polarized cell. This may be considered as one of the chains of cooperative cell polarization.     

Cloning and sequencing of immunoglobin lambda-chain cDNA in american mink (Mustela vison

cDNA library in the lambda gt11 phage was constructed using poly (A+)-mRNA from mink spleen as a template. Immunoscreening of the library allowed the identification of 2 lambda-related clones containing 370 and 803 bp insertion (lambda IGL-1 and lambda IGL-2). Analysis of the primary structure of lambda IGL-2 demonstrated that it contains a large portion of V lambda-segment, J lambda-segment, C lambda-gene and its 3'-untranslated part. The nucleotide sequences known for the immunoglobulin genes were compared to the sequence of the lambda IGL-2 clone. The highest degree of homology was established for the rabbit lambda-genes, this being 63, 94 and 72% for the RF3 region of V lambda-segment, J lambda-segment and C lambda-region, respectively.     

Effects of radiation-ecological conditions and experimental hyperthyroid states on indicators of testis and prostate androgen receptors in rats

Dose-dependent changes of the molecular characteristics on androgen receptor (AR) systems in gonads of male rats were studied at experimental L-thyroxine-induced states after low doses irradiation exposures in different reference points of 10-km Chernobyl zone. The data obtained suggest a generalized working mechanism of "oscillatorous changes" for contents, affinities and cooperative properties of AR to its natural ligands as a "mirror" reflecting some adaptational reactions in target cells that modulates their androgen-controlled biochemical activity.     

Radiation Inactivation of Coronavirus Infection Pathogen by the Example of Transmissible Gastroenteritis Virus

Biophysics - In recent years, members of the Coronaviridae family have caused outbreaks of respiratory diseases (MERS, SARS, and COVID-19). At the same time, the potential of radiation-induced...     

Rnq1 protein protects [<Emphasis Type="Italic">PSI</Emphasis><Superscript>+</Superscript>] prion from effect of the <Emphasis Type="Italic">PNM</Emphasis> mutation

The interaction of [PSI ⁺] and [PIN ⁺] factors in yeast Saccharomyces cerevisiae is known as the first evidence of prions networks. In [PIN ⁺] cells, Rnq1p prion aggregates work as a template for Sup35p aggregation, which is essential for [PSI ⁺] induction. No additional factors are required for subsequent Sup35p aggregation. Nevertheless, several recent reports provide data that indicate a more complex interplay between these prions. Our results show that the presence of Rnq1p in the cell significantly decreases the loss of [PSI ⁺] prion, which is caused by a double mutation in SUP35 (Q61K, Q62K substitutions in the Sup35 protein). These observations support the existence of interaction networks that converge on a strong linkage of prionogenic and prion-like proteins, and the participation of Rnq1 protein in the maintenance of prion [PSI ⁺].     

Contemporary molecular-biological methods of cancer diagnosis and monitoring based on the humoral immune response to tumor-associated antigens

Humoral immune response to tumor-associated antigens in cancer patients can be used as a basis for disease diagnosis and monitoring. Moreover, identification of molecular targets of such response may be used to develop antigen-specific anticancer vaccines. Here, we review the main approaches to identification and study of tumor-associated antigens recognized by serum antibodies. We also focus on the challenges that must be met before serological antigens can be used in clinical cancer diagnostics.     

Artificially applied tensions normalize development of relaxed Xenopus Laevis embryos

Relaxation of tensions of the surface of Xenopus laevis embryos at the late blastula stage leads to deep and diverse developmental defects and increased variability in mutual position and volume ratios of the axial rudiments. Here, we demonstrate that the development of such embryos was markedly normalized if the relaxed tensions were restored in one of two ways: (1) isotropic stretching of the blastocoel roof induced by incubation of relaxed embryos in a hypotonic medium or (2) anisotropic stretching of embryos on two needles. In the latter case, we succeeded in restoring the morphological axis not only after longitudinal stretching, but also after transverse stretching, and the new axis had signs of anteroposterior polarity. The role of isotropic and anisotropic tensions in organization of the early amphibian development is discussed.