Publications by authors named "Kazutoshi Yoshitake"

Purpose: Achromatopsia (ACHM) is an early-onset cone dysfunction caused by 5 genes with cone-specific functions (, , , and ) and by , a transcription factor with ubiquitous expression. To improve the relatively low variant detection ratio in these genes in a cohort of exome-sequenced Japanese patients with inherited retinal diseases (IRD), we performed genome sequencing to detect structural variants and intronic variants in patients with ACHM.

Methods: Genome sequencing of 10 ACHM pedigrees was performed after exome sequencing.

View Article and Find Full Text PDF

Pufferfish of the genus Takifugu possess tetrodotoxin (TTX), known as "pufferfish toxin" and it is believed that pufferfish eggs and newly hatched larvae utilize TTX as a defensive substance against predators. However, the mechanism for the placement of TTX to specific cells on the larval body surface during the developmental process remains unknown. In this study, we clarify the distribution and characteristics of TTX-rich cells.

View Article and Find Full Text PDF

Purpose: To ascertain the characteristics of achromatopsia (ACHM) in Japan by analyzing the genetic and phenotypic features of patients with ACHM.

Methods: The medical records of 52 patients from 47 Japanese families who were clinically diagnosed with ACHM were reviewed in this retrospective observational study.

Results: Thirty-six causative variants of ACHM were identified in 26 families via whole-exome sequencing: PDE6C (12 families), CNGA3 (10 families), CNGB3 (two families), and GNAT2 (two families).

View Article and Find Full Text PDF

Numerous biologically active natural products have been discovered from marine sponges, particularly from Theonella swinhoei, which is known to be a prolific source of natural products such as polyketides and peptides. Recent studies have revealed that many of these natural products are biosynthesized by Candidatus Entotheonella phylotypes, which are uncultivated symbionts within T. swinhoei.

View Article and Find Full Text PDF

Tetrodotoxin (TTX), a pufferfish toxin, is a highly potent neurotoxin that has been found in a wide variety of animals. The TTX-bearing flatworm Planocera multitentaculata possesses a large amount of TTX and is considered responsible for the toxification of TTX-bearing animals such as pufferfish (Takifugu and Chelonodon) and the toxic goby Yongeichthys criniger. However, the mechanism underlying TTX accumulation in flatworms remains unclear.

View Article and Find Full Text PDF

Small non-coding RNAs (sncRNAs) are non-coding RNA molecules that play various roles in metazoans. Among the sncRNAs, microRNAs (miRNAs) guide post-translational gene regulation during cellular development, proliferation, apoptosis, and differentiation, while PIWI-interacting RNAs (piRNAs) suppress transposon activity to safeguard the genome from detrimental insertion mutagenesis. While an increasing number of piRNAs are being identified in the soma and germlines of various organisms, they are scarcely reported in molluscs.

View Article and Find Full Text PDF
Article Synopsis
  • Tetrodotoxin (TTX), a powerful neurotoxin found in pufferfish, blocks sodium channels in muscle and nerve tissues and has also been found in marine flatworms, indicating bioaccumulation through food webs.
  • Research identified that the TTX and its analogs present in the flatworm Planocera multitentaculata were the same as those in the toxic pufferfish Takifugu alboplumbeus, but different from a non-toxic flatworm species.
  • A toxification experiment showed that wild pufferfish can reproduce the toxin composition of flatworms when fed certain diets, highlighting the significance of TTX in marine food webs and predator-prey interactions.
View Article and Find Full Text PDF

Phylogenetic evidence suggests a shared ancestry between mitochondria and modern Proteobacteria, a phylum including several genera of intracellular pathogens. Studying these diverse pathogens, particularly during intracellular infection of their hosts, can reveal characteristics potentially representative of the mitochondrial-Proteobacterial ancestor by identifying traits shared with mitochondria. While transcriptomic approaches can provide global insights into intracellular acclimatization by pathogens, they are often limited by excess host RNAs in extracts.

View Article and Find Full Text PDF
Article Synopsis
  • * Studying nudibranchs and their association with Symbiodiniaceae could help understand these important symbiotic processes better, as their cellular and histological details are still not fully clear.
  • * Research using advanced microscopy techniques shows that specific cells in nudibranchs can capture and manage the algae, offering valuable data on the mechanisms behind the algae's "bleaching" and overall marine symbiotic relationships.
View Article and Find Full Text PDF

Introduction: Congenital X-linked retinoschisis (XLRS) presents as macular retinoschisis/degeneration in almost all patients and as peripheral retinoschisis in half the patients. Although the optical coherence tomography (OCT) findings of macular retinoschisis have been well investigated, those of peripheral retinoschisis have rarely been reported. This study aimed to report the ultra-widefield OCT findings of the peripheral retina in patients with XLRS.

View Article and Find Full Text PDF

Two kahalalide analogues were isolated from a sp. marine green alga. Even though our initial structure determination of the peptides by NMR and MS identified them as kahalalide Z (KZ; ) and Z (KZ; ), the absolute configuration of the Thr residues by Marfey's analysis was different from those found in kahalalide F (KF), , and .

View Article and Find Full Text PDF

We report the complete genome sequence of sp. NBRC12716 isolated from a diseased eel in 1962. The genome consists of a single, circular chromosome 3,771,060 bp in length with 59.

View Article and Find Full Text PDF
Article Synopsis
  • MacFarland 1909 is a diverse type of nudibranch found in the Pacific and Western Atlantic.*
  • Researchers constructed its complete mitochondrial genome using advanced sequencing technology, which measures 14,291 base pairs and contains 13 protein-coding genes, 2 rRNA genes, and 23 tRNA genes.*
  • Molecular analysis confirmed that MacFarland 1909 belongs to the Aeolidioidea superfamily and is closely related to another nudibranch from the Aeolidiidae family, supporting previous taxonomic classifications and paving the way for future studies.*
View Article and Find Full Text PDF

Here, we report the first telomere-to-telomere genome assembly of matsutake (Tricholoma matsutake), which consists of 13 sequences (spanning 161.0 Mb) and a 76 kb circular mitochondrial genome. All the 13 sequences were supported with telomeric repeats at the ends.

View Article and Find Full Text PDF

Many studies have investigated the ability of environmental DNA (eDNA) to identify the species. However, when individual species are to be identified, accurate estimation of their abundance using traditional eDNA analyses is still difficult. We previously developed a novel analytical method called HaCeD-Seq (haplotype count from eDNA by sequencing), which focuses on the mitochondrial D-loop sequence for eels and tuna.

View Article and Find Full Text PDF
Article Synopsis
  • Risso's dolphin is a migratory marine mammal found in tropical and temperate seas, currently classified as least concern by the IUCN, but its population details remain uncertain.
  • A draft genome of the Risso's dolphin was assembled from samples in Japan, revealing a genome size of 2.256 Gb and identifying 9947 genes for potential study.
  • The genetic data obtained through advanced sequencing techniques will aid future research on dolphins and other marine mammals, enhancing understanding of their genetics and population structure.
View Article and Find Full Text PDF
Article Synopsis
  • Inherited retinal diseases (IRDs) are diverse eye disorders leading to vision loss due to retinal degeneration, with retinitis pigmentosa (RP) being the most common type.
  • A study involving 1210 IRD families in Japan identified 67 causal genes in 37% of these cases, primarily focusing on genetic mutations in EYS and RP1 genes.
  • The research highlighted a frequent missense variant in the EYS gene and identified two known mutations linked to autosomal recessive RP, along with a notable RP1 variant linked to autosomal recessive macular dystrophy/cone-rod dystrophy.
View Article and Find Full Text PDF

Environmental DNA (eDNA) is organismal DNA that can be detected in the environment and is derived from cellular material of organisms shed into aquatic or terrestrial environments. It can be sampled and monitored using molecular methods, which is important for the early detection of invasive and native species as well as the discovery of rare and cryptic species. While few reviews have summarized the latest findings on eDNA for most aquatic animal categories in the aquatic ecosystem, especially for aquatic eDNA processing and application.

View Article and Find Full Text PDF

Normal-tension glaucoma (NTG) is a heterogeneous disease characterized by retinal ganglion cell (RGC) death leading to cupping of the optic nerve head and visual field loss at normal intraocular pressure (IOP). The pathogenesis of NTG remains unclear. Here, we describe a single nucleotide mutation in exon 2 of the methyltransferase-like 23 (METTL23) gene identified in 3 generations of a Japanese family with NTG.

View Article and Find Full Text PDF

The molluscan shell is a good model for understanding the mechanisms underlying biomineralization. It is composed of calcium carbonate crystals and many types of organic molecules, such as the matrix proteins, polysaccharides, and lipids. The pen shell Atrina pectinata (Pterioida, Pinnidae) has two shell microstructures: an outer prismatic layer and an inner nacreous layer.

View Article and Find Full Text PDF

Most mammals, including humans, show obvious aging phenotypes, for example, loss of tissue plasticity and sarcopenia. In this regard, fish can be attractive models to study senescence because of their unique aging characteristics. The lifespan of fish varies widely, and several species can live for over 200 years.

View Article and Find Full Text PDF

Fish exhibit different muscle structures and growth characteristics compared with mammals. We used a spatial transcriptomics approach and examined myotomal muscle sections from zebrafish. Adult muscles were divided into eight regions according to spatial gene expression characteristics.

View Article and Find Full Text PDF

Acromegaly is a growth hormone (GH) excess pathological condition in humans. Acromegaly is associated with somatic disfigurement and a wide range of systemic manifestations such as arthritis, neuropathy, carpal tunnel syndrome, reproductive disorders, metabolic disorders, and gastrointestinal complications. The influence of excess GH on the cellular level could aid in understanding the root causes of acromegaly-related health complications.

View Article and Find Full Text PDF

Exosomes, a subset of small extracellular vesicles, carry various nucleic acids, proteins, lipids, amino acids and metabolites. They function as a mode of intercellular communication and molecular transfer. Exosome cargo molecules, including small non-coding RNAs (sncRNAs), are involved in the immune response in various organisms.

View Article and Find Full Text PDF