A5047326060- Aquatic Invertebrate Ecology and Behavior
- Marine Bivalve and Aquaculture Studies
- Calcium Carbonate Crystallization and Inhibition
- Fish Ecology and Management Studies
- Bone Tissue Engineering Materials
- Fish Biology and Ecology Studies
- RNA and protein synthesis mechanisms
- Marine and fisheries research
- Gene expression and cancer classification
- Genomics and Chromatin Dynamics
- Reproductive Biology and Fertility
- Genetic diversity and population structure
- Aquaculture Nutrition and Growth
- Parasite Biology and Host Interactions
- Reproductive biology and impacts on aquatic species
- DNA and Biological Computing
- Ancient Egypt and Archaeology
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Cephalopods and Marine Biology
- Food Industry and Aquatic Biology
- Marine Sponges and Natural Products
- Genetic Mapping and Diversity in Plants and Animals
- Genetic and Kidney Cyst Diseases
- Renal and related cancers
- Paleontology and Stratigraphy of Fossils
Chuo University
2021-2023
Research Institute of Environment, Agriculture and Fisheries, Osaka Prefecture
2014
Mie University
2000-2013
Kindai University
2005-2010
Experimental Station
2005
Two shell color types of the exotic bivalve Corbicula fluminea were collected in Kyoto city, Japan. DNA microfluorometry revealed that both diploids with non-reductional spermatozoa. Maternal chromosomes found to be extruded as two polar bodies at first meiosis, and second meiosis could not observed. Only male pronucleus was present egg cytoplasm became metaphase mitosis. The study indicates diploid C. Japan has same mode androgenetic reproduction triploid leana.
Expression patterns of the shell matrix protein genes MSI31 and MSI60 in pearl sac epithelium were examined by situ hybridization 38 days after implantation, related to quality. A that produced a nacreous showed very weak expression strong MSI60. sac, which yielded prismatic pearl, strongly expressed weakly In complex whose surface consisted mosaic both layers, pattern similarly corresponded underlying structures pearl. had an entirely composed laminar structure with unusual tablet growth at...
The timing of primordial germ-cell (PGC) migration with regard to the gonadal anlagen, gonad formation and sex differentiation was examined histologically in chub mackerel (Scomber japonicus) at 5–190 days post hatching (dph). At 5 dph, PGCs appeared on peritoneal epithelium surface or mesentery, dorsal side abdominal cavity. By 10 stromal cells around proliferated. primordium formed by 15 dph. gonadosomatic index 0.01% 30 dph increased thereafter (0.32% females 0.04% males 160 dph). Ovarian...
We investigated the phylogeography of Asian brackish water clam, Corbicula japonica, to clarify its demographic history using partial mitochondrial COII gene sequences (990 bp) from 283 individuals collected around Japanese archipelago and adjacent areas. Phylogenetic analyses revealed presence two major groups within our samples: monophyletic Group I comprising Lineages A-E C. japonica paraphyletic II consisting sp. A-C were distributed in Japan Sakhalin Island, D, E, Korean Peninsula....
We propose a hypothesis of ploidy elevation in the androgenetic clam Corbicula fluminea, based on an abnormal process fertilization clams collected at Tone River, Ibaraki Prefecture, Japan. Most eggs showed androgenesis, that is, extrusion all maternal chromosomes as two polar bodies during first meiotic division. did not form female pronucleus, but only male pronucleus. However, some proceeded to second meiosis and formed both The formation pronucleus suggests may have occurred by aberrant...
The production of a cultured pearl is the result complex interplay between donor and recipient oysters. However, there paucity information on relationship oyster gene expression patterns quality. Shell matrix proteins affect not only formation shell, but also that pearls. We compared five shell (msi60, nacrein, msi31, prismalin-14, aspein) in mantle edge (ME), which forms prismatic layer, center (MC), nacreous high- (HP) low quality pearl- (LP) producing After culturing for about two months,...
We observed spermatozoa of five freshwater Japanese unionid mussel species under a light microscope. Males discharged as spherical masses. Spermatozoa embedded their heads into spherical, colorless body with tails extended around the sphere. termed this mass sperm “sperm sphere”. Just after release spheres rotated rapidly by synchronous movement tails. By next day, increased in size and some had detached from spheres. sphere were active at least forty-eight hours being discharged. Single...
The hermaphroditic diploid clam Corbicula fluminea reproduces by androgenesis. In the control (androgenetic development), all maternal chromosomes and centrosomes at meiotic poles were extruded as two first polar bodies subsequently second meiosis did not occur. eggs treated with cytochalasin D (CD) to inhibit body extrusion, was abortive. After meiosis, spindle remained in cytoplasm because of effect CD. divided into groups anaphase‐I observed eggs. Two four just after but separate...
The positions of enhancers and promoters on genomic DNA remain poorly understood. Chromosomes cannot be observed during the cell division cycle because genome forms a chromatin structure spreads within nucleus. However, high-throughput chromosome conformation capture (Hi-C) measures physical interactions genomes. In previous studies, extrusion loops were directly derived from Hi-C heat maps. Multidimensional Scaling (MDS) is used in this assessment to more precisely locate promoters. MDS...