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Tabunoki, H.

Publications and source records attributed to Tabunoki, H..

2 recordsLinked to original sources

Long-read genome assembly of the Japanese parasitic wasp Copidosoma floridanum (Hymenoptera: Encyrtidae)

Copidosoma floridanum is a cosmopolitan species and an egg-larval parasitoid of the Plusiine moth. C. floridanum has a unique development mode called polyembryony, in which thousands of genetically identical embryos are produced from a single egg. Some embryos develop into sterile soldier larvae, and their developmental patterns differ between the US and Japanese C. floridanum strains. Genome sequencing can accelerate our understanding of the molecular bases underlying polyembryony, including the production of soldier castes. However, only the genome sequence of the US strain has been reported. In the present study, we determined the genome sequence of the Japanese strain using Pacific Biosciences high-fidelity reads and generating a highly contiguous assembly (552.7 Mb, N50: 17.9 Mb). Gene prediction and annotation identified 13,886 transcripts derived from 10,786 gene models. We searched the genomic differences between US and Japanese strains. Among gene models predicted in this study, 100 gene loci in the Japanese strain had extremely different gene structure from those in the US strain. This was accomplished through the functional annotation (GGSEARCH) and long-read sequencing. Genomic differences between strains were also reflected to amino acid sequences of vasa that plays a central role in caste determination in this species. The genome assemblies constructed in this study will facilitate the genomic comparisons between Japanese and US strains, leading to our understanding of detail genomic regions responsible for the ecological and physiological characters of C. floridanum.

genomics↗

Systematic functional annotation workflow for insects

Next generation sequencing has revolutionized entomological study, rendering it possible to analyze the genomes and transcriptomes of non-model insects. However, use of this technology is often limited to obtaining nucleotide sequences of target or related genes, with many of the acquired sequences remaining unused because other available sequences are not sufficiently annotated. To address this issue, we have developed a functional annotation workflow for transcriptome-sequenced insects to determine transcript descriptions, which represents a significant improvement over the previous method (functional annotation pipeline for insects). The developed workflow attempts to annotate not only the protein sequences obtained from transcriptome analysis but also the ncRNA sequences obtained simultaneously. In addition, the workflow integrates the expression level information obtained from transcriptome sequencing for application as functional annotation information. Using the workflow, functional annotation was performed on the sequences obtained from transcriptome sequencing of stick insect (Entoria okinawaensis) and silkworm (Bombyx mori), yielding richer functional annotation information than that obtained in our previous study. The improved workflow allows more comprehensive exploitation of transcriptome data and is applicable to other insects because the workflow has been openly developed on GitHub. Simple SummaryThe function of all genes encoded in the genome should be studied for genome editing. The genome editing technology can speeds up insect research for functional analysis of genes. Our knowledge about the functional information of genes is still incomplete currently while genome sequencing of an organism can be completed. The functional information has been annotated based solely on the information that has been obtained from the result of previous biological research. However, this information will be important in determining the target genes for genome editing. In particular, it is very important that this information is in machine-readable form because computer programs mainly parse this information for the understanding of biological systems. In this paper, we describe a workflow-based method for annotating gene functions in insects that make use of transcribed sequence information as well as reference genome and protein sequence databases. Using the developed workflow, we annotated functional information of Japanese stick insect and silkworm, including gene expression as well as sequence analysis. The functional annotation information obtained by the workflow will greatly expand the possibilities of entomological research using genome editing.

bioinformatics↗