The eEF1 family of mammalian translation elongation factors.

The eEF1 family of mammalian translation elongation factors is comprised of the two variants of eEF1A (eEF1A1 and eEF1A2), and the eEF1B complex. The latter consists of eEF1Bα, eEF1Bß, and eEF1Bγ subunits. The two eEF1A variants have similar translation activity but may differ with respect to their secondary, "moonlighting" functions. This variability is underlined by the difference in the spatial organization of eEF1A1 and eEF1A2, and also possibly by the differences in their post-translational modifications. Here, we review the data on the spatial organization and post-translation modifications of eEF1A1 and eEF1A2, and provide examples of their involvement in various processes in addition to translation. We also describe the structural models of eEF1B subunits, their organization in the subcomplexes, and the trimeric model of the entire eEF1B complex. We discuss the functional consequences of such an assembly into a complex as well as the involvement of individual subunits in non-translational processes.

[Obtaining and characteristics of domestic preparation interferon alpha-2b with prolonged effect].

Pegylated interferon alpha-2b (PEG-IFN alpha-2b) is a domestic preparation of a modified recombinant interferon alpha-2b with prolonged effect. The preparation was obtained by N-terminal pegylation of IFN alpha-2b with polyethylene glycol (PEG). This paper presents the method of PEG-IFN alpha-2b synthesis and characteristics of the obtained product. PAAG electrophoresis, Western blot analysis and MALDI-TOF mass-spectrometry confirm that the preparation is an N-terminal pegylated IFN alpha-2b that contains no more than 10% of dipegylated IFN alpha-2b. The comparison of PEG-IFN alpha-2b with its foreign analogue has revealed the similarity of their biological activity and pharmacokinetic parameters.

The proteome of maize leaves: use of gene sequences and expressed sequence tag data for identification of proteins with peptide mass fingerprints.

As a first step in establishing a proteome database for maize, we have embarked on the identification of the leaf proteins resolved on two-dimensional (2-D) gels. We detected nearly 900 spots on the gels with a pH 4-7 gradient and over 200 spots on the gels with a pH 6-11 gradient when the proteins were visualized with colloidal Coomassie blue. Peptide mass fingerprints for 300 protein spots were obtained with matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometer and 149 protein spots were identified using the protein databases. We also searched the pdbEST databases to identify the leaf proteins and verified 66% of the protein spots that had been identified using the protein databases. Sixty-seven additional protein spots were identified from expressed sequence tags (ESTs). Many abundant leaf proteins are present in multiple spots. Functions of over 50% of the abundant leaf proteins are either unknown or hypothetical. Our results show that EST databases in conjunction with peptide mass fingerprints can be used for identifying proteins from organisms with incomplete genome sequence information.

Ligand blot analysis of juvenile hormone esterase binding proteins in Manduca sexta L.

Biotinylated recombinant juvenile hormone esterase (JHE) was used for ligand blotting of proteins from fat body tissue and pericardial athrocytes of Manduca sexta. Proteins were separated by SDS-polyacrylamide gel electrophoresis or by two-dimensional electrophoresis. Eight putative JHE binding proteins were detected in fat body tissue and in pericardial athrocytes of both M. sexta and Heliothis virescens. The predominant bands were 29, 72, 75, 125 and 240kDa, with minor bands at 50, 80 and 205kDa. All putative JHE binding proteins were present from the second through to the fifth instar larvae of M. sexta. On wide-range isoelectric focusing, the 29kDa JHE binding protein separated into three species with isoelectric points of 6.5, 6.6 and 6.8. Biotinylated-JHE did not bind recombinant M. sexta-derived juvenile hormone binding protein. The mutant JHE with mutations K29R and K524R binds weakly to the JHE binding protein P29, relative to binding of wild-type JHE [Shanmugavelu et al., J. Biol. Chem., 275 (2000) 1802-1806]. A similar reduction in binding was not seen for the 29kDa binding protein identified here in pericardial athrocytes by ligand blot. This result is discussed.

Proteomics: a powerful tool in the post-genomic era.

Genomics is having a profound impact on biological research, including photosynthesis investigations. Genomes of many photosynthetic organisms have been sequenced. The information about ALL genes that govern and execute photoautotrophic metabolism provides many opportunities to understand genome function and details of known and uncharted pathways. Proteomics, analysis of the protein complement of the genome, is a powerful tool in understanding which proteins are present in a particular tissue under given conditions. Proteomics also allows us to estimate relative levels of proteins and to determine post-translational modifications of the gene products. In this minireview, we discuss the technology and its applications in plant sciences.

Effect of clinostating on photosynthetic apparatus of pea plants.

The photosynthetic membrane composition and low temperature fluorescence spectra were analyzed for pea chloroplasts from control and clinostated plants. Clinorotation induces a decrease in the amount of the oligomeric form of the light-harvesting chlorophyll a/b complex (LHCII) and an increase of its monomeric form. Some changes in organization of photosystem 1 (PS1) complex were revealed as well. These changes are in accordance with the variations of fluorescence characteristics and photochemical activity.