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Sato, M. P.

Publications and source records attributed to Sato, M. P..

3 recordsLinked to original sources

CAP peptide artificially induces insect gall

Galls caused by gall-inducing insects in their host plants clearly illustrate the concept of extended phenotype, which refers to traits expressed in a host organism when manipulated by a parasite. Candidate effector molecules involved in gall formation, such as phytohormones, amino acids, and proteins, have been reported in numerous studies. However, to date, no attempts to artificially regenerate gall structures using effector candidates have been reported. In this study, we tested the peptide from Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins, CAP peptide as a gall-inducing effector candidate obtained from transcripts isolated from the horned gall aphid, (Schlechtendalia chinensis) through in silico screening and the Arabidopsis-based gall-forming assay, which is a bioassay system for analysing the molecular mechanisms of gall formation. Furthermore, we succeeded in generating an artificial gall in the host plant Veronica peregrina, without any insect parasitism, using three minimal effector elements: CAP peptide, auxin, and cytokinin. Given the strong similarities observed in organ structure with a central cavity and three types of tissue and gene expression patterns between the native and artificial galls, we concluded that CAP peptide is a general gall-inducing effector peptide secreted by gall-inducing insects.

molecular biology↗

Telomere-to-telomere genome assembly of an allotetraploid pernicious weed, Echinochloa phyllopogon

Echinochloa phyllopogon is an allotetraploid pernicious weed species found in rice fields worldwide that often exhibits resistance to multiple herbicides. An accurate genome sequence is essential to comprehensively understand the genetic basis underlying the traits of this species. Here, the telomere-to-telomere genome sequence of E. phyllopogon was presented. Eighteen chromosome sequences spanning 1.0 Gb were constructed using the PacBio highly-fidelity long technology. Of the 18 chromosomes, 12 sequences were entirely assembled into telomere-to-telomere and gap-free contigs, whereas the remaining six sequences were constructed at the chromosomal level with only eight gaps. The sequences were assigned to the A and B genomes with total lengths of 453 and 520 Mb, respectively. Repetitive sequences occupied 42.93% of the A genome and 48.47% of the B genome, although 32,337, and 30,889 high-confidence genes were predicted in the A and B genomes, respectively. This suggested that genome extensions and gene disruptions caused by repeated sequence accumulation often occur in the B genome before polyploidization to establish a tetraploid genome. The highly accurate and comprehensive genome sequence would contribute to elucidating the population structure of this species and could be a milestone in understanding the molecular mechanisms of the pernicious traits and to developing effective weed control strategies to avoid yield loss in rice production.

genomics↗

Telomere-to-telomere genome assembly of matsutake (Tricholoma matsutake)

Here, we report the first telomere-to-telomere genome assembly of matsutake (Tricholoma matsutake), which consists of 13 chromosomes (spanning 160.7 Mb) and a 76 kb circular mitochondrial genome. The chromosome sequences were supported with telomeric repeats at the ends. GC-rich regions are located at the middle of the chromosomes and are enriched with long interspersed nuclear elements (LINEs). Repetitive sequences including long-terminal repeats (LTRs) and LINEs occupy 71.7% of the genome. A total of 28,322 potential protein-coding genes and 324 tRNA genes were predicted. Sequence and structure variant analysis revealed 2,322,349 single nucleotide polymorphisms and 102,831 insertions and deletions, 0.6% of which disrupted gene structure and function and were therefore classified as deleterious mutations. As many as 683 copies of the LTR retrotransposon MarY1 were detected in the matsutake genome, 91 of which were inserted in gene sequences. In addition, 187 sequence variations were found in the mitochondrial genome. The genomic data reported in this study would serve as a great reference for exploring the genetics and genomics of matsutake in the future, and the information gained would ultimately facilitate the conservation of this vulnerable genetic resource.

genomics↗