Publications by authors named "Sergei A Lavrov"
Article Synopsis
- The RNA helicase Spindle-E (Spn-E) is crucial for the piRNA silencing process in Drosophila, specifically in the reproductive organs where it helps prevent retrotransposon mobilization and gene derepression.* -
- Research on spn-E heterozygous flies showed a significant presence of piRNA ping-pong pairs linked to Su(Ste) transcripts, but these levels dropped sharply in spn-E mutant flies.* -
- The absence of Spn-E led to a notable decrease in key proteins involved in the ping-pong mechanism, Aubergine and AGO3, suggesting that Spn-E might play a role in post-transcriptional regulation rather than affecting their overall synthesis.*
Theoretical models suggest that gene silencing at the nuclear periphery may involve "closing" of chromatin by transcriptional repressors, such as histone deacetylases (HDACs). Here we provide experimental evidence confirming these predictions. Histone acetylation, chromatin compactness, and gene repression in lamina-interacting multigenic chromatin domains were analyzed in Drosophila S2 cells in which B-type lamin, diverse HDACs, and lamina-associated proteins were downregulated by dsRNA.
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- Polytene chromosomes in D. melanogaster exhibit underrepresentation of heterochromatic pericentric regions, specifically in relation to the X-linked Stellate repeats.
- The study reveals that when a Stellate cluster fragment is transposed into euchromatin, it gets replicated in polytene chromosomes, particularly those near newly formed eu-heterochromatic boundaries.
- Internal rearrangements of the distal Xh don't impact Stellate replication, but trans effects from heterochromatic regions can influence the replication of these rearranged sequences, suggesting a role for heterochromatic proteins in their underrepresentation.
The mechanism of silencing of testis expressed X-linked Stellate repeats by homologous Y-linked Suppressor of Stellate [Su(Ste)] repeats localized in the crystal locus was studied. The double stranded RNA as a product of symmetrical transcription of Su(Ste) repeat and small interference Su(Ste) siRNA were revealed suggesting the mechanism of RNA interference (RNAi) for Stellate silencing. The relief of Stellate silencing as a result of impaired complementarity between the sequences of putative target Stellate transcripts and Su(Ste) repeats was shown.
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