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Lazarev, V.

Publications and source records attributed to Lazarev, V..

4 recordsLinked to original sources

NanoMOFs with Encapsulated Photosensitizer: Accumulation in Chlamydia trachomatis Inclusions and Antimicrobial Effects

Metal-organic framework nanoparticles (nanoMOFs) are a promising class of hybrid nanomaterials for biomedical applications. Some of them, including biodegradable porous iron carboxylates are proposed for encapsulation and delivery of antibiotics. Due to the high drug loading capacity and fast internalization kinetics nanoMOFs are more beneficial for the treatment of intracellular bacterial infections compared to free antibacterial drugs, which poorly accumulate inside the cells because of the inability to cross membrane barriers or have low intracellular retention. However, nanoparticle internalization does not ensure their accumulation in the cell compartment that shelters a pathogen. This study shows the availability of MIL-100(Fe) MOF nanoparticles to co-localize with Chlamydia trachomatis, an obligate intracellular bacterium, in the infected RAW264.7 macrophages. Furthermore, nanoMOFs loaded with photosensitizer methylene blue (MB) exhibit complete photodynamic inactivation of Chlamydia trachomatis growth. Simultaneous infection and treatment of RAW264.7 cells with empty nanoMOFs resulted in a 3-fold decrease in bacterial load that indicates an intrinsic anti-chlamydial effect of this iron-containing nanomaterial. Thus, our findings suggest the use of iron-based nanoMOFs as a promising drug delivery platform, which contributes to antibacterial effect, for the treatment of chlamydial infections.

biophysics↗

RALF peptides modulate immune response in the moss Physcomitrium patens

RAPID ALKALINIZATION FACTOR (RALFs) are cysteine-rich peptides that regulate multiple physiological processes in plants. This peptide family has considerably expanded during land plant evolution, but the role of ancient RALFs in modulating stress response is unknown. Here, we used the moss Physcomitrium patens as a model to gain insight into the role of RALF peptides in coordination of plant growth and stress response in non-vascular plants. The quantitative proteomic analysis revealed concerted downregulation of M6 metalloproteases and some membrane proteins, including those involved in stress response, in PpRALF1, 2 and 3 knockout (KO) lines. We found that knockout of PpRALF2 and PpRALF3 genes resulted in increased resistance to bacterial and fungal phytopathogens - Pectobacterium carotovorum and Fusarium solani, suggesting the role of these peptides in negative regulation of immune response in P. patens. The comparative transcriptome analysis of PpRALF3 KO and wild type plants under Fusarium solani infection showed the clear difference in regulation of genes belonging to phenylpropanoid pathway and associated with cell wall modification and biogenesis between these genotypes. The follow-up analysis revealed the role of PpRALF3 in growth regulation under abiotic and biotic stress regulation, which suggests the role of RALFs in responses to different adverse conditions. Thus, our study sheds light on the function of the previously uncharacterized PpRALF3 peptide and gives a clue to ancestral functions of RALF peptides in plant stress response.

plant biology↗

FAMOSS, a conserved 41-aa peptide involved in plant tip growth regulation

Recent evidence shows that small open reading frame (smORF; <100 codons)-encoded peptides (SEPs) containing transmembrane domains are preadapted to be progenitors of novel functional genes. A dozen of such SEPs translated from long non-coding RNAs (lncRNAs) are already functionally characterised in animals. However, functional plant lncRNA-smORF-coded peptides are not yet described. Here, we report detailed functional characterization of a 41-aa peptide encoded by lncRNA-smORFs in the moss Physcomitrium patens, which was named "FAst-growing MOSS" (FAMOSS). We found that the FAMOSS interacts with the Rab-type small GTPase proteins and its overexpression leads to faster moss growth rate and more intensive vesicular transport in apical cells, while its knockout results in the opposite effect. The FAMOSS contains a predicted transmembrane domain and possible orthologs from streptophyta algae to flowering plants have a very conserved structure. Thus, the FAMOSS peptide is a previously unknown conserved player of Rab-mediated processes in plants. Our findings are in line with functional studies of transmembrane SEPs in animals and prove the principles of SEPs evolution. This study provides new insights into functions of plant lncRNA-smORFs.

plant biology↗

Distinct types of short open reading frames are translated in plant cells

Genomes contain millions of short (<100 codons) open reading frames (sORFs), which are usually dismissed during gene annotation. Nevertheless, peptides encoded by such sORFs can play important biological roles, and their impact on cellular processes has long been underestimated. Here, we analyzed approximately 70,000 transcribed sORFs in the model plant Physcomitrella patens (moss). Several distinct classes of sORFs that differ in terms of their position on transcripts and the level of evolutionary conservation are present in the moss genome. Over 5000 sORFs were conserved in at least one of ten plant species examined. Mass spectrometry analysis of proteomic and peptidomic datasets suggested that 584 sORFs located on distinct parts of mRNAs and long non-coding RNAs (lncRNAs) are translated, including 73 conservative sORFs. Translational analysis of the sORFs and main ORFs at a single locus suggested the existence of genes that code for multiple proteins and peptides with tissue-specific expression. Alternative splicing is likely involved in the excision of translatable sORFs from such transcripts. We identified a group of sORFs homologous to known protein domains and suggested they function as small interfering peptides. Functional analysis of candidate lncRNA-encoded peptides showed it to be involved in regulating growth and differentiation in moss. The high evolutionary rate and wide translation of sORFs suggest that they may provide a reservoir of potentially active peptides and their importance as a raw material for gene evolution. Our results thus open new avenues for discovering novel, biologically active peptides in the plant kingdom.

plant biology↗