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S L Kiselev

Publications and source records attributed to S L Kiselev.

48 records · Page 3Linked to original sources
PubMed1989

Mobile genetic elements in Drosophila melanogaster (recent experiments).

Recent data obtained in the authors' laboratories concerning the behaviour of mobile genetic elements of Drosophila melanogaster are reviewed. It was found that the mobile element jockey represents the typical LINE element. It is efficiently transcribed in D. melanogaster cells in flies and in culture. Transcription is initiated from the +1 nucleotide of jockey and depends on an internal promoter. This is the first case of an internal promoter being used by RNA polymerase II. Several events which take place during the transposition bursts in ctMR2 family of strains were described. Among them are the removal of mobile dispersed genetics (mdg) elements (with solo long terminal repeat (LTR) remaining at the site of excision), complete removal of an mdg element, and reinsertion of the same mdg to the same place either in the presence or in absence of solo LTR sequence. Finally, the formation of deletions was observed. A 462-bp deletion destroying the white locus can be further repaired (w+ reversion). Thus, transposition bursts include many different genetic events. A novel system of prolonged genome destabilization was described. It depends on mobilization of a new mobile element called Stalker. After certain crosses Stalker actively moves for dozens of generations giving rise to large numbers of insertion mutations. Several novel genes were detected using mobilized Stalker. They include a modifier of mdg4 and six enhancers of yellow mutations.

Animals↗
PubMedDate not supplied

[The use of the two-hybrid cloning in yeast for functional characterization of protein kinase MAK-V].

Identification of interaction partners opens a way to direct functional characterization of proteins. Several cDNAs coding for potential partners of protein kinase MAK-V/Hunk were isolated using two-hybrid cloning in yeast. Based on the partner properties, MAK-V/Hunk was assumed to play a role in tumorigenesis and tumor progression. With the previous results of two-hybrid cloning, MAK-V/Hunk was shown to participate in vesicular transport.

Cadherins↗
PubMedDate not supplied

[Variants of adenovirus type 5 with deletions in early genes: ability for selective replication in p53-defective human tumor cells].

Site-directed mutagenesis was used to construct human adenovirus serotype 5 (Ad5) variants defective in E1A or E1B. Mutant Adel3 with deletion from E1A was markedly attenuated in permissive cell cultures regardless of the p53 status, and replicated efficiently only in cells of the complementing 293 line. Mutant Adel2 with deletion from E1B55K infected the 293 line cells and p53-deficient human tumor cells (A431, SW480, HEp2) with efficiencies similar to those of Ad5, whereas its replication in normal p53-positive cells was substantially limited. Thus, Adel2 proved to be capable of selective infection and lysis of p53-deficient human tumor cells in vitro. On intratumor injection, Adel2 dramatically suppressed the growth of human epidermoid carcinoma (A431) in nude mice. Adel2 is thus a promising model for designing therapeutic agents against p53-deficient human tumors.

Adenoviridae↗
PubMedDate not supplied

[Proteinkinase MAK-V/Hunk as a possible dianostic and prognostic marker of human breast carcinoma].

We propose a system for detection of overproduction of protein kinase MAK-V/Hunk in tumours. MAK-V/ Hunk overproduction is observed in about 50% breast carcinomas. Positive staining is obseved in tumour cells only and has mainly cytoplasmic characteristics. Increased production of MAK-V/Hunk does not correlate with histological type of carcinoma, metastasizing, steroid receptor status (estrogen and progesterone), proliferative activity. Tumours positive for MAK-V/ Hunk were more frequently observed in c-erbB2-positive (3+) tumours than in c-erbB2-negative ones. Overproduction of MAK-V/Hunk in human breast cancer may be used fore more precise molecular typing of this tumour, in particular in case of c-erbB2-positive tumors, however, diagnostic-prognostic value of this new molecular marker needs further studies.

Adult↗
PubMedDate not supplied

[Primary structure of the 5S rRNA gene and its flanking sequences in diploid Aegilops tauschii Coss].

In genome of diploid aegilops A. tauschii (k773) two types of sequences 420 and 510 b. p. long which hybridize with 5S[32P]rRNA were discovered. Using the plasmid pBR327 the recombinant plasmids pAt5S79 and pAt5S91 containing 5S DNA repeats of Ae. tauschii were constructed. The primary structure of 5S rRNA gene and that of intergene spacer cloned in pAt5S79 was determined. In gene region of Ae. tauschii coding for 5S rRNA, as compared with T. aestivum, there were found 3 base substitutions in positions 24, 36 and 37. The homology of spacer sequences is 79.1%. In 5S rRNA gene of Ae. tauschii GC-content is 53.3%, but in a spacer--48.1%. The terminator of transcription in Ae. tauschii includes 15 AT-base pairs with predomination of T-bases in uncoding chain.

DNA↗