[Physiological and biochemical characteristics of recalcitrant seed under the condition of true dormancy: a review].

The review considers and sums up the results of studies of physiological and biochemical characteristics of dormant and germinating recalcitrant seed (the object of the study, the seed of common horse chestnut, Aesculus hippocastanum L., is viewed as an exemplary case). The results of analysis of the proteomes of the axis and cotyledons have been studied and the effects of the stratification, assessed. Gene expression has been studied at the level of protein synthesis; the protein-synthesizing capacity of the cells of the embryonic axis and cotyledon storage parenchyma of mature seed and seed undergoing stratification. The extent to which the functionally active translation machinery of ripe seed depends on transcription has been assessed, and the ability to synthesize protein under the conditions of stratification has been established. It is concluded that the embryonic axis of dormant seed lacks innate dormancy and that the isolated axis exhibits diverse sensitivity to exogenous abscisic acid and other physiologically active compounds.

[Ribosomal proteins of pea seeds behaving like anions at pH 8.6]. / Belki ribosom semian gorokha, vedushchie sebia kak aniony pri pH 8.6.

A group of proteins migrating to the anode at pH 8.6 under polyacrylamide gel electrophoresis was revealed in the total protein of non-dissociated KCl-washed pea seed ribosomes. No proteins with an isoelectric point below pH 4.2 Were found. The presence of acidic proteins in 80 S ribosomes is due to the presence of a specific set of relatively acidic proteins in the total protein of large (5 major and 10 minor components) and small (2 major and 4 minor components) subunits. The mostly acidic proteins are located in the large subunit. The acidic proteins of 60S and 40S subunits are represented by the polypeptide chains with molecular weights from 48 000 to 13 000. The acidic proteins are present in the ribosomes studied in considerably less number than the basic proteins, and the former produce a very weak staining under electrophoretic analysis as compared with the latter. The data obtained suggest that 80S ribosomes of higher plants differ from animal ribosomes by a higher content of relatively acidic proteins.

[Studies of basic proteins of 60S- and 40S-subunits of pea seed ribosomes by two-dimensional polyacrylamide gel electrophoresis]. / Osnovnye belki 60S-i 40S--subchastits ribosom semian gorokha, izuchennye metodom 2-mernogo elektroforeza v poliakrilamidnom gele.

Basic proteins of 60S- and 40S-subunits of pea seed ribosomes were studied by two-dimensional electrophoresis in polyacrylamide gel (PAAG) with subsequent electrophoresis of separated proteins in the gels containing sodium dodecyl sulfate. The proteins under study were found to be electrophoretically heterogenous and showed considerable variations in the staining by amido black and a specific distribution between the two subunits. 47 protein components were detected in the protein preparations of the 60S subunit: 18--as intensively stained, 12--as moderately stained and 17--as weakly stained spots. Presumably, the 60S subunit does not contain proteins whose molecular weights are over 60.000 or below 14.000. Two proteins have mol. weight over 50.000; other proteins have mol. weights varying between 15.000 and 30.000. 32 proteins components were revealed in the protein preparations of the 40S subunit: 15--as intensively coloured, 8--as moderately coloured and 9--as weakly coloured spots. The 40S subunit does not contain proteins whose molecular weights are over 33.000 and below 10.000. Three proteins have mol. weights over 30.000, the other proteins have mol. weights within the interval of 15.000--30.000. The amount of basic proteins in the 80S plant ribosomes is, in all probability, higher as compared to that in animal ribosomes, and this is due to the 60S subunit.

[Analysis of ribosomal proteins and ribosomal subunits of pea seeds by electrophoresis in polyacrylamide gel]. / Izuchenie Belkov Ribosom I Ribosomnykh Sub'edinits Semian Gorokha Metodom Zlektroforeza v Poliakrilamidnom gele

The amino acid composition of overall protein of ribosomes and ribosomal subunits of pea seeds has been found typical of ribosomal protein. Electrophoresis in polyacrylamide gel demonstrates that proteins extracted by the solution of 3 M LiCl-4 M urea from purified ribosomes of pea seeds move towards the cathode at pH 2.2 and separate into 41 components. Electrophoresis in a tris-glycine buffer at pH 9.2 does not reveal any substance corresponding to acid proteins. Similar distribution patterns are observed when ribosomal particles are isolated with or without triton (0,5%). The treatment of ribosomes by deoxycholate results in some changes, depending on the detergent concentration. All the protein components detected in ribosomes, except one, are present in the subunits. Proteins of large and small ribosome subunits produced 26 and 21 components respectively in polyacrylamide gel electrophoresis. The distribution patterns of proteins of the two subunits appear to be different. The majority of the components of the large and small subunits differ in mobility. The data obtained suggest considerable specificity of the protein composition of 60S and 40S subunits of 80S ribosomes in higher plants.