[Water-soluble proteins in early amphibian embryos. III. Immunoelectrophoretic analysis of the antigenic changes in the ectoderm of the early gastrula and neural plate during development]. / Vodorastvorimye belki rannikh zarodyshei amfibii. III. Immunoélektroforeticheskii analiz izmenenii antigenov éktodermy rannei gastruly i nervnoi plastinki v razvitii.

20 water-soluble antigen have been identified with the help of rabbit antisera to extracts of the early gastrula ectoderm and neural plate in Rana temporaria. All of them were also found in the early blastula embryos and unfertilized eggs. The identified antigens are characterized by a definite embryospecificity. As the development proceeds, the concentration of these antigens in the embryonic tissues decreases until the complete disappearance of corresponding immunoelectrophoretic reactions. By this characteristic all antigens under study are subdivided into four groups: I--five antigens identified at the early developmental stages only (until hatching, stage 29); II--nine antigens present up to stages 33--35; III--three antigens followed up to stages 39--40 (well formed tadpole); IV--three antigens were found at all developmental stages under study up to stages 45--47. 11 out of 20 identified antigens have antigenic similarity with the proteins of blood serum of adult amphibians. Besides, the early gastrula ectoderm contains antigens similar with those of the brain of adult amphibians.

[Isoelectric focusing with silver impregnation of proteins]. / Izoélektrofokusirovanie s impregnatsiei belkov serebrom.

Silver impregnation of polyacrylamide gel sheets after isoelectrofocusing is described. This method of staining allows to increase the sensitivity of the traditional isoelectrofocusing 5 to 10 times, as compared with staining of gels by Coumassi brilliant-blue R-250 (in case of analysis of complex protein mixtures). When analyzing individual protein preparations, the sensitivity of isoelectrofocusing with silver staining is within the range of several dozens of ng per sample. A special attention is paid to methods permitting to decrease the non-specific background staining of gel by silver.