Biology subjects

Nagata, T.

Publications and source records attributed to Nagata, T..

3 recordsLinked to original sources

bioRxiv2020

Date palm virus A: first plant virus found in date palm trees

In this work, a novel ssRNA (+) viral genomic sequence with gene organization typical of members of the subfamily Quinvirinae (family Betaflexiviridae) was identified using high throughput sequencing data of date palm obtained from the Sequence Read Archive database. The viral genome sequence consists of 7860 nucleotides and contains five ORFs encoding for the replication protein (Rep), triple gene block proteins 1, 2, 3 (TGB 1, 2 and 3) and coat protein (CP). Phylogenetic analysis based on the Rep and the CP amino acid sequences showed the closest relationship to garlic yellow mosaic-associated virus (GYMaV). Based on the demarcation criteria of the family Betaflexiviridae, this new virus, provisionally named date palm virus A (DPVA), could constitute a member of a novel genus. However, considering that DPVA and GYMaV share the same genomic organization and that they cluster together on the Rep phylogenetic analysis, they could also constitute a novel genus together, highlighting the necessity of a revision of the taxonomic criteria of the family Betaflexiviridae.

plant biology↗

bioRxiv2020

Heterogeneity in the response of different subtypes of Drosophila melanogaster enteroendocrine cells to viral infections

Single cell RNA sequencing (scRNA-seq) offers the possibility to monitor both host and pathogens transcriptomes at the cellular level. Here, public scRNA-seq data from Drosophila melanogaster have been used to compare the differences in replication strategy and cellular response between two viruses, Thika virus (TV) and D. melanogaster Nora virus (DMelNV) in enteroendocrine cells (EEs). TV and DMelNV exhibited different patterns of replication and for TV, accumulation varied according to cell subtype. Cells infected with TV underwent down-regulation of genes that represent bottlenecks in the fruit fly interactome, while cells infected with DMelNV went through a down-expression of translation-related genes that represent both hubs and bottlenecks in the host interactome. In contrast, flies infected with DMelNV show only a systemic level down-regulation of bottleneck genes. Here, we use scRNA-seq to highlight the differences and commonalities between cellular response to TV and DMelNV and between cellular and systemic response to DMelNV.

systems biology↗

bioRxiv2020

Exploration of natural red-shifted rhodopsins using a machine learning-based Bayesian experimental design

Microbial rhodopsins are photoreceptive membrane proteins utilized as molecular tools in optogenetics. In this paper, a machine learning (ML)-based model was constructed to approximate the relationship between amino acid sequences and absorption wavelengths using ~800 rhodopsins with known absorption wavelengths. This ML-based model was specifically designed for screening rhodopsins that are red-shifted from representative rhodopsins in the same subfamily. Among 5,558 candidate rhodopsins suggested by a protein BLAST search of several protein databases, 40 were selected by the ML-based model. The wavelengths of these 40 selected candidates were experimentally investigated, and 32 (80%) showed red-shift gains. In addition, four showed red-shift gains > 20 nm, and two were found to have desirable ion-transporting properties, indicating that they were potentially useful in optogenetics. These findings suggest that an ML-based model can reduce the cost for exploring new functional proteins.

biochemistry↗