Elina Avanesyan

Saint Petersburg State University, Sankt-Peterburg, St.-Petersburg, Russia

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Publications (8)6.75 Total impact

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    Dataset: GENE 2010

    Full-text · Dataset · Oct 2013
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    ABSTRACT: The tissue-specific accumulation of small bristles (Dm nxf1) transcripts at different developmental stages of Drosophila melanogaster was analyzed by Northern blots and RT PCR. We identified four distinct transcripts: ubiquitous (3.5 kb); ovary and early embryo specific (3.3 kb); testis specific (1.9 kb and 2.8 kb) and nervous system specific (5.1 kb). The pattern of Dm nxf1 gene expression in ovaries and early embryos (0–2 h) is similar: the sizes of transcripts range from 3.0 to 3.5 kb. We propose that this size variability may reflect the different extent of cytoplasmic polyadenylation. In testes, the 2.8-kb transcript originates from alternative termination of transcription and the 1.9-kb transcript is supposed to originate from an alternative transcription start. During ontogenesis, the 5.1-kb transcript can be clearly detected in 10- to 18-h-old embryos, most prominently in the nervous ganglia of larvae, and it represents a major species in imago head extracts. We found that the 5.1-kb transcript, similarly to the nxf1 heavy transcripts in Homo sapiens and Mus musculus, results from the retention of intron 5–6 that corresponds to the intron 10–11 in Hs nxf1 and Mm nxf1 genes.
    Full-text · Dataset · Oct 2013
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    ABSTRACT: Abstract The small bristles (sbr) gene of Drosophila melanogaster belongs to the family of nuclear export factor (NXF) genes that participate in mRNA nuclear export. During meiosis, females of Drosophila melanogaster that carry various combinations of mutant alleles of the Dm nxf1/sbr gene exhibit disruption of the division spindle and misalignment of chromosomes at the metaphase plate. Meiosis of sbr5/+ females is characterized by the formation of tripolar spindles during the first cell division. According to the sequencing results, the sbr5 (l(1)K4) lethal allele is a deletion of 492 nucleotides. In SBR5 protein, 57 of the 146 amino acids that have been lost by deletion belong to the NTF2-like domain.
    Full-text · Dataset · Sep 2013
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    ABSTRACT: The tissue-specific accumulation of small bristles (Dm nxf1) transcripts at different developmental stages of Drosophila melanogaster was analyzed by Northern blots and RT PCR. We identified four distinct transcripts: ubiquitous (3.5 kb); ovary and early embryo specific (3.3 kb); testis specific (1.9 kb and 2.8 kb) and nervous system specific (5.1 kb). The pattern of Dm nxf1 gene expression in ovaries and early embryos (0–2 h) is similar: the sizes of transcripts range from 3.0 to 3.5 kb. We propose that this size variability may reflect the different extent of cytoplasmic polyadenylation. In testes, the 2.8-kb transcript originates from alternative termination of transcription and the 1.9-kb transcript is supposed to originate from an alternative transcription start. During ontogenesis, the 5.1-kb transcript can be clearly detected in 10-to 18-h-old embryos, most prominently in the nervous ganglia of larvae, and it represents a major species in imago head extracts. We found that the 5.1-kb transcript, similarly to the nxf1 heavy transcripts in Homo sapiens and Mus musculus, results from the retention of intron 5–6 that corresponds to the intron 10–11 in Hs nxf1 and Mm nxf1 genes.
    Full-text · Dataset · Oct 2010
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    ABSTRACT: Spermatogenesis in both the model object Drosophila melanogaster and mammals, including humans, is characterized by the specificity of the regulation of gene expression at both the transcriptional and translational levels, which is manifested in the existence of testis-specific transport mRNA receptors, NXF (nuclear export factor). By using antibodies to the C-terminal part of the Dm NXF1 protein (SBR), a considerable amount of this protein is found to be present at all stages of spermatogenesis. At early stages of spermatogenesis, we have shown the cytoplasmic localization of the Dm NXF1 protein. This protein is located in the nucleus or in the nuclear envelope at the stage of rounded spermatids. During spermatid elongation, the Dm NXF1 protein is located polarly and disposed only along one side of the extended spermatid nucleus, while, at the stage of spermatid individualization, it is translocated into the spermatozoan tail in the form of large cytoplasmic granules. Key wordstransport mRNA-spermatogenesis-Drosophila-NXF
    Full-text · Article · Oct 2010 · Cell and Tissue Biology
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    ABSTRACT: The tissue-specific accumulation of small bristles (Dm nxf1) transcripts at different developmental stages of Drosophila melanogaster was analyzed by Northern blots and RT PCR. We identified four distinct transcripts: ubiquitous (3.5kb); ovary and early embryo specific (3.3kb); testis specific (1.9kb and 2.8kb) and nervous system specific (5.1kb). The pattern of Dm nxf1 gene expression in ovaries and early embryos (0-2h) is similar: the sizes of transcripts range from 3.0 to 3.5kb. We propose that this size variability may reflect the different extent of cytoplasmic polyadenylation. In testes, the 2.8-kb transcript originates from alternative termination of transcription and the 1.9-kb transcript is supposed to originate from an alternative transcription start. During ontogenesis, the 5.1-kb transcript can be clearly detected in 10- to 18-h-old embryos, most prominently in the nervous ganglia of larvae, and it represents a major species in imago head extracts. We found that the 5.1-kb transcript, similarly to the nxf1 heavy transcripts in Homo sapiens and Mus musculus, results from the retention of intron 5-6 that corresponds to the intron 10-11 in Hs nxf1 and Mm nxf1 genes.
    Full-text · Article · Mar 2010 · Gene
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    ABSTRACT: Specificity of regulation of genes expression at the transcriptional and posttranscriptional levels is typical for spermatogenesis in Drosophila and mammals, including humans. It becomes apparent in the existence of testis specific NXF (nuclear export factor). We have shown that the Dm NXF1 (SBR) protein is present in considerable amounts at all stages of the spermatogenesis. Using the antibody for the C-terminal part of the Dm NXF1 protein we have shown the cytoplasmic localization of the Dm NXF1 protein at early stages of the spermatogenesis. This protein is localized in the nuclear envelope at thestage of rounded spermatid. During the period of elongation, the Dm NXF1 protein has a polar localization, and is located only along oneside of the extended spermatid nucleus. At the stage of spermatid individualization, this protein in the form of large cytoplasmic granules moves to the tail of the spermatozoon.
    Full-text · Article · Jan 2010
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    ABSTRACT: The small bristles (sbr) gene of Drosophila melanogaster belongs to the family of nuclear export factor (NXF) genes that participate in mRNA nuclear export. During meiosis, females of Drosophila melanogaster that carry various combinations of mutant alleles of the Dm nxf1/sbr gene exhibit disruption of the division spindle and misalignment of chromosomes at the metaphase plate. Meiosis of sbr 5 /+ females is characterized by the formation of tripolar spindles during the first cell division. According to the sequencing results, the sbr 5 (l(1)K4) lethal allele is a deletion of 492 nucleotides. In SBR5 protein, 57 of the 146 amino acids that have been lost by deletion belong to the NTF2-like domain.
    Full-text · Article · Sep 2009 · Chromosome Research