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Romanowski, V.

Publications and source records attributed to Romanowski, V..

7 recordsLinked to original sources

MicroRNAome of Spodoptera frugiperda in Response to SfMNPV Infection

Spodoptera frugiperda is one of the most important agronomical pests due to its migratory capacity and broad host range. Since it is resistant to several insecticides, novel control strategies are being explored to control it. In this way, Spodoptera frugiperda Multiple Nucleopolyhedrovirus, a natural pathogen, has been proposed for its biocontrol. In this work, we performed a small RNA-seq on uninfected larvae and larvae infected with SfMNPV to identify expressed miRNA, characterize them, and identify differentially expressed (DE) miRNA in the infected condition. We identified several known and putative novel miRNAs, some of which are encoded in multiple copies and may be expressed within miRNA clusters. We also found 13 DE miRNA, most of them previously reported, two of them are putative novel miRNAs identified in this work. We predicted miRNA targets and found that their putative biological role could be related with processes relevant to the infection such as proliferative and apoptotic pathways, cell cycle regulation, autophagy, DNA damage response (DDR), vesicle transport, cytoskeleton remodelling, JAK/STAT and Toll signaling pathway, and immune response activation, among others. Moreover, we observed that several of the putative targets were hub genes in a predicted protein - protein interaction network. Finally, we found DE miRNA putatively associated with the regulation of viral gene expression, suggesting they might have a role in modulating the infection. Our results contribute to better understanding the miRNA landscape in S. frugiperda, and their putative role upon SfMNPV infection.

molecular biology↗

Proteomic Characterization of Spodoptera frugiperda Granulovirus Occlusion Bodies

Lepidopteran-infecting baculoviruses represent one of the most promising alternatives for pest biocontrol. In particular, Spodoptera frugiperda granulovirus (SfGV) infects the fall armyworm Spodoptera frugiperda, an increasingly important pest for maize and other crops around the world. SfGV has been investigated due to its capacity to enhance other baculovirus infectivity and as a biopesticide itself. Although the proteome of SfGV occlusion bodies (OB) is fundamental for their infectivity properties, we still lack a detailed understanding of its protein components and how they compare with other baculoviruses. To tackle this problem, we performed mass spectrometry-based proteomics analysis on SfGV OB obtained from infected larvae. We could detect 72 proteins included in SfGV OB and confirm the presence of two enhancins. EmPAI-based semi-quantification highlighted the presence of two granulovirus proteins, ORF101 and ORF141, shared with other GV proteomic studies. ORF101 was shown to form aggregates in insect cells. Bioinformatic analysis determined that ORF101 is an Ac5 family protein and at the same time shares striking similarities with AcMNPV P10. Prediction and comparison of OB protein structures allowed the detection of a common structural fold among 6 proteins PEP-1, PEP-2, Pep-P10, ORF007, ORF025, and Bro-f. Finally, comparison of four reported ODV proteomic studies of different GVs indicated that ORF040, ORF101, ORF141 and Bro-f are common components in GV OBs.

molecular biology↗

Role of RIPK1 in Diffuse Gliomas pathology

PurposeThe aim of the present work was to investigate the role of Receptor-interacting protein kinase 1 (RIPK1) both in mutated and wild type isocitrate dehydrogenase (IDH) Diffuse Gliomas (DG). Patients and MethodsWe analyzed RIPK1 mRNA expression in DG databases from The Cancer Genome Atlas (TCGA) containing clinical, genomic and transcriptomic information from 661 patients. Transcriptomic studies (mRNA expression levels, correlation heatmaps, survival plots and Gene Ontology and meta-analysis of immune gene signatures) were performed with USC Xena and R. Statistical significance was set at p-values less than 0.05. ResultsThe results showed a lower survival probability in patients belonging to the high RIPK1 expression subgroup compared to those samples with low RIPK1 expression. We also observed a higher expression of RIPK1 in wtIDH samples compared to those with mIDH. In order to further characterize the role of RIPK1 in DG, we performed a Gene Ontology and Pathway Enrichment Analysis using the Xena platforms differential expression tool. The results showed that RIPK1 is involved in inflammatory and immune responses. Hence, the expression levels of some of the genes involved in the following molecular processes crucial for cancer progression were studied: proliferation, epithelial-mesenchymal transition, immune cell infiltration and cell death pathways. Briefly, the results showed significant differences in genes related to increased cellular dedifferentiation, proinflammatory cell death pathways and tumor infiltrating immune cells gene signatures (Welchs t-test). ConclusionRIPK1 over-expression is associated with a poor prognosis in DG. This fact, together with our results suggest that RIPK1 may play a crucial role in glioma pathogenesis highlighting the need to take into account RIPK1 expression levels for decision making when choosing or designing therapeutic alternatives. CONTEXT SUMMARYO_ST_ABSKey ObjectiveC_ST_ABSEvaluate the role of the Receptor-interacting protein kinase 1 (RIPK1) in Diffuse Gliomas (DG) pathology through an exhaustive in silico patient database analysis. Knowledge generatedWe demonstrated that RIPK1 is overexpressed in more aggressive DG and correlates with clinical attributes associated with poor prognosis. In addition, our analyses showed that high RIPK1 expression correlates with key genes involved in pro inflammatory cell death pathways and an increased expression of immune gene signatures suggesting greater immunological infiltration in the tumor. RelevanceOur results from patient database analyses propose RIPK1 as a new relevant molecular prognosis marker for DG. Our findings are in concordance with different preclinical studies and provide additional information that can be useful for decision making when choosing therapeutic strategies and for the development of novel therapeutic approaches such as gene or immunotherapy. This work was presented inXIII Argentine Congress of Bioinformatics and Computational Biology (XIII CAB2C), XIII International Conference of the Iberoamerican Society of Bioinformatics (XIII SoIBio) and III Annual Meeting of the Ibero-American Artificial Intelligence Network for Big BioData (III RiaBio).

bioinformatics↗

Exploring the metastatic role of the inhibitor of apoptosis BIRC6 in Breast Cancer

Breast cancer is the most common cancer as well as the first cause of death by cancer in women worldwide. BIRC6 (baculoviral IAP repeat-containing protein 6) is a member of the inhibitors of apoptosis protein family thought to play an important role in the progression or chemoresistance of many cancers. The aim of the present work was to investigate the role of apoptosis inhibitor BIRC6 in breast cancer, focusing particularly on its involvement in the metastatic cascade. We analyzed BIRC6 mRNA expression levels and Copy Number Variations (CNV) in three breast cancer databases from The Cancer Genome Atlas (TCGA) comparing clinical and molecular attributes. Genomic analysis was performed using CBioportal platform while transcriptomic studies (mRNA expression levels, correlation heatmaps, survival plots and Gene Ontology) were performed with USC Xena and R. Statistical significance was set at p-values less than 0.05. Our analyses showed that there was a differential expression of BIRC6 in cancer samples when compared to normal samples. CNV that involve amplification and gain of BIRC6 gene were correlated with negative hormone receptor tumors, higher prognostic indexes, younger age at diagnosis and both chemotherapy and radiotherapy administration. Transcriptomic and gene-ontology analyses showed that, in conditions of high BIRC6 mRNA levels, there are differential expression patterns in apoptotic, proliferation, and metastatic pathways. In summary, our in silico analyses suggest that BIRC6 exhibits an antiapoptotic, pro-proliferative and an apparent pro-metastatic role and could be a relevant molecular target for treatment of Breast Cancer tumors.

molecular biology↗

Genomic Diversity in a Population of Spodoptera frugiperda Nucleopolyhedrovirus

Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) represents a strong candidate to develop environmental-friendly pesticides against the fall armyworm (Spodoptera frugiperda), a widespread pest that poses a severe threat to different crops around the world. However, little is known regarding the genomic diversity present inside SfMNPV isolates and how it shapes the interactions between virus and host. Here, the genomic diversity present inside an isolate of SfMNPV was explored using high-throughput sequencing for the first time. We identified 704 intrahost single nucleotide variants, from which 184 are nonsynonymous mutations distributed among 82 different coding sequences. We detected several structural variants affecting SfMNPV genome, including two previously reported deletions inside the egt region. A comparative analysis between polymorphisms present in different SfMNPV isolates and our intraisolate diversity data suggests that coding regions with higher genetic diversity are associated with oral infectivity or unknown functions. In this context, through molecular evolution studies we provide evidence of diversifying selection acting on sf29, a putative collagenase which could contribute to the oral infectivity of SfMNPV. Overall, our results contribute to deepen our understanding of the coevolution between SfMNPV and the fall armyworm and will be useful to improve the applicability of this virus as a biological control agent. HighlightsO_LIWe characterized the genomic diversity within a population of SfMNPV. C_LIO_LICoding regions with higher genetics diversity are associated with oral infectivity or unknown functions. C_LIO_LISeveral structural variants contribute to the genomic diversity of SfMNPV. C_LIO_LISf29, a putative collagenase, shows signs of adaptive evolution. C_LI

microbiology↗

Evolutionary and Structural Constraints Influencing Apolipoprotein A-I Amyloid Behavior

Apolipoprotein A-I (apoA-I) has a key function in the reverse cholesterol transport mediated by the high density lipoprotein (HDL) particles. However, aggregation of apoA-I single point mutants can lead to hereditary amyloid pathology. Although several studies have tackled the biophysical and structural impacts introduced by these mutations, there is little information addressing the relationship between the evolutionary and structural features that contribute to the amyloid behavior of apoA-I. We combined evolutionary studies, in silico mutagenesis and molecular dynamics (MD) simulations to provide a comprehensive analysis of the conservation and pathogenic role of the aggregation-prone regions (APRs) present in apoA-I. Sequence analysis demonstrated that among the four amyloidogenic regions described for human apoA-I, only two (APR1 and APR4) are evolutionary conserved across different species of Sarcopterygii. Moreover, stability analysis carried out with the FoldX engine showed that APR1 contributes to the marginal stability of apoA-I. Structural properties of the full-length apoA-I model suggest that aggregation is avoided by placing APRs into highly packed and rigid portions of its native fold. Following we set up to study the effect of natural mutations on protein conformation and stability. Compared to natural silent variants extracted from the gnomAD database, the thermodynamic and pathogenic impact of apoA-I amyloid mutations showed evidence of a higher destabilizing effect. MD simulations of the amyloid variant G26R evidenced the partial unfolding of the alpha-helix bundle with the concomitant exposure of APR1 to the solvent and the formation of beta-sheet segments at the C-terminus of apoA-I, giving a possible hint about the early steps involved in its aggregation. Our findings highlight APR1 as a relevant component for apoA-I structural integrity and emphasize a destabilizing effect of amyloid variants that leads to the exposure of this region. This information contributes to our understanding of how apoA-I, with its high degree of structural flexibility, maintains a delicate equilibrium between its monomeric native structure and intrinsic tendency to form amyloid aggregates. In addition, our stability measurements could be used as a proxy to interpret the structural impact of new mutations.

bioinformatics↗

\"Protein composition of the occlusion bodies of Epinotia aporema granulovirus\"

Within family Baculoviridae, members of the Betabaculovirus genus are employed as biocontrol agents against lepidopteran pests, either alone or in combination with selected members of the Alphabaculovirus genus. Epinotia aporema granulovirus (EpapGV) is a fast killing betabaculovirus that infects the bean shoot borer (E. aporema) and is a promising biopesticide. Because occlusion bodies (OBs) play a key role in baculovirus horizontal transmission, we investigated the composition of EpapGV OBs. Using mass spectrometry-based proteomics we could identify 56 proteins that are included in the OBs during the final stages of larval infection. Our data provides experimental validation of several annotated hypothetical coding sequences. Proteogenomic mapping against genomic sequence detected a previously unannotated ac110-like core gene and a putative translation fusion product of ORFs epap48 and epap49. Comparative studies of the proteomes available for the family Baculoviridae highlight the conservation of core gene products as parts of the occluded virion. Two proteins specific for betabaculoviruses (Epap48 and Epap95) are incorporated into OBs. Moreover, quantification based on emPAI values showed that Epap95 is one of the most abundant components of EpapGV OBs.

microbiology↗