Biology subjects

Shidlovskii, Y. V.

Publications and source records attributed to Shidlovskii, Y. V..

3 recordsLinked to original sources

bioRxiv2025

Stability of orb mRNA in Drosophila ovaries is regulated by cis-regulatory elements in the three prime untranslated region and influences germ cell specification

Orb is one of two Drosophila mRNA-binding CPEB proteins that activate or repress translation by mediating polyadenylation and deadenylation of target mRNAs through interaction with CPE motifs in their 3UTRs. Orb is one of the key regulators of oocyte specification and polarity. This regulation acts through establishment and maintenance of a 3UTR-dependent positive autoregulatory loop. In 16-cell cysts, positive autoregulation is necessary to accumulate high levels of orb mRNA and protein in one of the two pro-oocytes. A previous study showed that deletion of the orb 3UTR fragment containing CPE sites leads to a failure in proper orb mRNA and protein localization; as a result, oocytes are not specified in 16-cell cysts, and egg chambers contain only nurse cells. In the present study, we found that deletion of CPE and CPE-like motifs disrupts proper Orb protein localization and oocyte specification in germaria. CPE motifs are indispensable for orb mRNA stability: deletion of CPE and CPE-like sequences reduces orb mRNA stability to one third of level in wild type. When the 3UTR is deleted, the remaining 115-nucleotide sequence, which does not include CPE motifs, is sufficient for nurse cell development. Removal of this sequence leads to a further decrease in orb mRNA stability and a drop of Orb protein to undetectable levels. Oogenesis stops in region 2a/2b of the germarium, where the checkpoint is localized, and egg chambers do not form. We propose that CPE motifs are required for orb 3UTR-mediated Orb accumulation which drives oocyte specification, whereas low levels of unlocalized Orb protein expressed in the absence of Orb autoregulation are sufficient for nurse cell specification.

cell biology↗

bioRxiv2024

Kolmogorov-Smirnov and Shapiro-Wilk single distribution analysis methods in examining sample structure, strength of genetic background, and effects of interventions in lifespan and aging studies

The analysis of lifespan and ageing involves a variety of calculations based on survival data. One of these is the comparison of survival curves. However, inspection of survival curves provides little information about the frequency of phenotypes within samples. Here we propose to divide the distribution into intervals to obtain information about the sample structure. Then, we apply the normality criterion to the distributions using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Using this approach, we reveal the destabilising effect of mutations on ontogenesis and lifespan, and estimate the strength of the genetic background of the lines. The proposed methodology allows effective estimation of sample structure and adds a new layer of information to longevity studies.

genetics↗

bioRxiv2020

PBAP chromatin remodeler mediates enhancer-driven transcription inDrosophila

Chromatin remodeler SWI/SNF is an important participant of gene activation acting predominantly by opening chromatin structure on promoters and enhancers. Here we describe its novel mode of action by mediating targeted action of enhancer. We studied functions of two signature subunits of PBAP subfamily, BAP170 and SAYP, in Drosophila. These subunits were stably tethered onto transgene reporter carrying hsp70 core promoter. Tethered subunits mediate transcription of reporter in a pattern prescribed by nearby enhancer in multiple loci throughout the genome, where the reporter construct was located. Both tethered SAYP and BAP170 recruit the whole PBAP complex onto reporter promoter. Studying difference between these subunits, we found that BAP170-dependent transcription is more resistant to depletion of other PBAP subunits, what may imply the principal role of BAP170 in establishing enhancer-dependent transcription. Author SummaryChromatin remodelers are key molecular machines that are responsible for local changes in chromatin structure in the nucleus. However, their functions in gene expression regulation seem to be broader. We describe the involvement of the SWI/SNF family of remodelers in establishing enhancer-promoter communication, which is apparently independent of its local remodeling activity. Using an artificial tethering of a remodeler on a promoter, we demonstrated that promoters of a certain type become responsive to activation by a nearby enhancer only in the presence of the remodeler, while a remodeler tethering itself is insufficient for gene activation. Thus, our approach helps to uncover novel aspects of molecular interplay on regulatory elements during the gene activation process.

genetics↗