Biology subjects

Igarashi, Y.

Publications and source records attributed to Igarashi, Y..

3 recordsLinked to original sources

bioRxiv2018

Transcriptome analysis of differential gene expression in Dichomitus squalens during interspecific mycelial interactions and the potential link with laccase induction

Interspecific mycelial interactions between white rot fungi are always accompanied by increased production of laccase. In this study, the potential of white rot fungi Dichomitus squalens for enhancing laccase production during interaction with two other white rot fungi Trametes versicolor or Pleurotus ostreatus was identified. To probe the mechanism of laccase induction and the role of laccase played during the combative interaction, we analyzed the laccase induction response to stressful conditions during fungal interaction related to the differential gene expression profile. We further confirmed the expression patterns of 16 selected genes by qRT-PCR analysis. We noted that many differential expression genes (DEGs) encoding proteins were involved in xenobiotics detoxification and ROS generation or reduction, including aldo/keto reductase, glutathione S-transferases, cytochrome P450 enzymes, alcohol oxidases and dehydrogenase, manganese peroxidase and laccase. Furthermore, many DEG-encoding proteins were involved in antagonistic mechanisms of nutrient acquisition and antifungal properties, including glycoside hydrolase, glucanase, chitinase and terpenoid synthases. DEGs analysis effectively revealed that laccase induction was likely caused by protective responses to oxidative stress and nutrient competition during fungal interspecific interaction.

bioinformatics↗

bioRxiv2018

Six species of non-tuberculosis mycobacteria carry non-identical 16S rRNA gene copies

Non-tuberculosis mycobacteria (NTM) can carry two or more 16S rRNA gene copies that are, in some instances, non-identical. In this study, we used a combined cloning and sequencing approach to analyze the 16S rRNA gene sequences of six NTM species, Mycobacterium cosmeticum, M. pallens, M. hodleri, M. crocinum, M. flavescens, and M. xenopi. The approach facilitated the identification of two distinct gene copies in each species. The two M. cosmeticum genes had a single nucleotide difference, whereas two nucleotide polymorphisms were identified in M. hodleri, M. flavescens, and M. xenopi. M. pallens had a difference in four nucleotides and M. crocinum in 23. Hence, we showed that the six NTM species possess at least two non-identical 16S rRNA gene copies.\n\nImportanceThe presence of multiple 16S rRNA gene copies with nucleotide polymorphisms represents a challenge for species identification using 16S rRNA as the target sequence. Our analysis was focused on six NTM species, M. cosmeticum, M. pallens, M. hodleri, M. crocinum, M. flavescens, and M. xenopi. As a result, we generated the full-length sequences of two non-identical 16S rRNA copies for each NTM species. The data will be helpful for the sequence analysis of specimens or other samples.

bioinformatics↗

bioRxiv2018

Designed hybrids facilitate efficient generation of high-resolution linkage maps

In sequencing eukaryotic genomes, linkage maps are indispensable for building scaffolds with which to assemble and/or to validate chromosomes. However, current approaches to construct linkage maps are limited by marker density and cost-effectiveness, especially for wild organisms. We have now devised a new strategy based on artificially generated hybrid organisms to acquire ultra high-density genomic markers at lower cost and build highly accurate linkage maps. Using this method, linkage maps and draft sequences for two species of pufferfish were obtained simultaneously. We anticipate that the method will accelerate genomic analysis of sexually reproducing organisms.

genomics↗