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S G Inge-Vechtomov

Publications and source records attributed to S G Inge-Vechtomov.

At least 73 records · Page 4Linked to original sources
PubMedDate not supplied

Divergence and conservation of SUP2 (SUP35) gene of yeast Pichia pinus and Saccharomyces cerevisiae.

SUP2 (SUP35) is an omnipotent suppressor gene, coding for an EF-1 alpha-like protein factor, intimately involved in the control of translational accuracy in yeast Saccharomyces cerevisiae. In the present study a SUP2 gene analogue from yeast Pichia pinus was isolated by complementation of the temperature-sensitive sup2 mutation of S. cerevisiae. The nucleotide sequence of the SUP2 gene of P. pinus codes for a protein of 82.4 kDa, exceeding the Sup2 protein of S. cerevisiae by 6 kDa. Like the SUP2 gene product of S. cerevisiae, the Sup2 protein of P. pinus represents a fusion of a unique N-terminal part and a region homologous to EF-1 alpha. The comparison of amino acid sequences of the Sup2 proteins reveals high conservation (76%) of the C-terminal region and low conservation (36%) of the N-terminal part where, in addition, the homologous correspondence is ambiguous. Proteins related to the Sup2 of S. cerevisiae were found in P. pinus and some other yeast species by the immunoblotting technique. The relation between the evolutionary conservation of different regions of the Sup2 protein and their functional significance is discussed.

Amino Acid Sequence↗
PubMedDate not supplied

[A possible role of genetic translation ambiguity in evolution ].

A hypothesis has been suggested that the variability of translation machinery is one of the key factors of evolutionary transformations of genetic material. It considers a module principle of the evolution theory based on the concepts of duplication and divergence of genetic material, which is required for origination of new genes and proteins with new functions. The duplication results in the appearance of pseudogenes, functionally inactive, but serving a material for creating new functions. The possible mechanisms changing the translation machinery have been considered, which may lead to the sporadic pseudogene activation "supplying" natural selection with mutational changes accumulated by pseudogenes to assess their adaptive value. This takes into account not only potential possibilities of mutational variability of the translation machinery, but also the possibility of protein prioritization: a prion mechanism of inheritance is also considered which is intensively studied nowadays.

Animals↗
PubMedDate not supplied

[Role of genetic processes in modification variability. Prophecy of B.L. Astaurov].

In his pioneering work on mutation tetraptera in Drosophila melanogaster, B.L. Astaurov discovered spontaneous modifications based on variability in gene expression. This new approach to the phenomenon of modifications should be considered as the first stimulus to development of the general theory of variability. Contemporary classification of variability based predominantly on phenomenology encounters many contradictions. The same specific molecular mechanisms may be responsible, for example, for both hereditary and nonhereditary variability depending on the taxonomic status. Some mechanisms responsible for both mutations and modifications or for mutations, recombination, and ontogenetic variability have been considered from this viewpoint. It may well be more productive to consider different types of variability with respect to the main genetic processes: replication and expression of genetic material.

Animals↗
PubMedDate not supplied

[Increased tRNA concentration in yeast containing mutant termination translation factors eRF1 and eRF3].

Earlier we have characterized strains bearing mutations in essential genes SUP45 and SUP35 of yeast S. cerevisiae, encoding translation termination factors eRF1 and eRF3 respectively. In the present work nonsense-mutants on genes SUP45 and SUP35 have been compared by a level of eight tRNA: tRNATyr, tRNAGln, tRNATrp, tRNALeu and tRNAArg (previously described as potentially suppressor tRNA), and also tRNAPro, tRNAHis and tRNAGly. We have not revealed preferable increase in amount of natural suppressor tRNA. The majority of the investigated mutations leads to increase in a level of all investigated tRNA. The mechanisms providing viability of nonsense-mutants on essential genes SUP45 and SUP35 are discussed.

Alleles↗
PubMedDate not supplied

[Comparative analysis of the structure of SUP2 genes in Pichia pinus and Saccharomyces cerevisiae].

SUP2(SUP35) is an omnipotent suppressor gene, coding for an EF-1 alpha-like protein factor, involved in the control of translational accuracy in yeast Saccharomyces cerevisiae. A SUP2 gene analogue from yeast Pichia pinus was isolated by complementation of temperature-sensitive sup2 mutation of S. cerevisiae. Nucleotide sequence of the SUP2 gene of P. pinus codes for a protein of 82.4 kDa exceeding the SUP2 protein of S. cerevisiae for 6 kDa. The SUP2 gene product of P. pinus is similar to the Sup2 protein of S. cerevisiae by its structure and includes a highly conservative (76%) C-terminal region homologus to EF-1 alpha and a lowly conservative N-terminal region. The relation between the evolutionary conservativity of different regions of the Sup2 protein and their functional significance is discussed.

Amino Acid Sequence↗