Genetic diversity of Sicyopterus japonicus as revealed by mitochondrial DNA sequencing

To examine the genetic diversity of Sicyopterus japonicus, 448 sites of the control region of the mitochondrial DNA were analyzed in 77 specimens from the four localities of Okinawa, Kochi, Wakayama, and Shizuoka in Japan. A total of 74 haplotypes were found in the individuals examined. The same haplotypes occurred in Okinawa and Kochi, Kochi and Wakayama, and two specimens in Wakayama. The average sequence in genetic characteristics within localities varied from 1.7% in Kochi, 1.6% in Wakayama to 1.4% in Okinawa. There was no significant difference in genetic characteristics among the three locations of Wakayama, Kochi, and Okinawa (10,000 times permutation test, P>0.05). The number of specimens from Shizuoka was too small to compare to the other three locations. The neighbor-joining tree of the mitochondrial DNA haplotypes for all specimens constructed from the Kimura\u27s two-parameter distances suggested no evidence of genetic subdivision of S. japonicus. These results suggested that this species has a single panmictic population and their larvae probably have a high dispersal ability during their oceanic stage

PERK eIF2α kinase regulates neonatal growth by controlling the expression of circulating insulin-like growth factor-I derived from the liver

Humans afflicted with the Wolcott-Rallison syndrome and mice deficient for PERK (pancreatic endoplasmic reticulum eIF2α kinase) show severe postnatal growth retardation. In mice, growth retardation in Perk−/− mutants is manifested within the first few days of neonatal development. Growth parameters of Perk−/− mice, including comparison of body weight to length and organ weights, are consistent with proportional dwarfism. Tibia growth plates exhibited a reduction in proliferative and hypertrophic chondrocytes underlying the longitudinal growth retardation. Neonatal Perk−/− deficient mice show a 75% reduction in liver IGF-I mRNA and serum IGF-I within the first week, whereas the expression of IGF-I mRNA in most other tissues is normal. Injections of IGF-I partially reversed the growth retardation of the Perk−/− mice, whereas GH had no effect. Transgenic rescue of PERK activity in the insulin- secreting β-cells of the Perk−/− mice reversed the juvenile but not the neonatal growth retardation. We provide evidence that circulating IGF-I is derived from neonatal liver but is independent of GH at this stage. We propose that PERK is required to regulate the expression of IGF-I in the liver during the neonatal period, when IGF-I expression is GH-independent, and that the lack of this regulation results in severe neonatal growth retardation

Development of biomimetic catalytic oxidation methods and non-salt methods using transition metal-based acid and base ambiphilic catalysts

This review focuses on the development of ruthenium and flavin catalysts for environmentally benign oxidation reactions based on mimicking the functions of cytochrome P-450 and flavoenzymes, and low valent transition-metal catalysts that replace conventional acids and bases. Several new concepts and new types of catalytic reactions based on these concepts are described

SARS-CoV-2 Omicron virus causes attenuated disease in mice and hamsters

The recent emergence of B.1.1.529, the Omicron varian

Validation of otolith daily increments in the amphidromous goby Sicyopterus japonicus

To determine the periodicity of growth increment deposition in the otoliths of newly recruited larvae of the amphidromous goby Sicyopterus japonicus, an otolith validation experiment was performed. Larval gobies collected at the river mouth of the Ota River, Wakayama, Japan were immersed in an alizarin complexone (ALC) solution to mark the timing in their otoliths. After being held under natural light conditions for 15 days, they were treated with ALC again to make the second time mark. The number of growth increments between two ALC marks in the otoliths was 14.1 on average, which roughly coincided with the number of days between two ALC treatments. This experiment validated the daily periodicity of otolith growth increment deposition in S. japonicus showing that the otolith increments of the species can be used for age determination with daily precision

Validation of otolith daily increments in the amphidromous goby Sicyopterus japonicus

To determine the periodicity of growth increment deposition in the otoliths of newly recruited larvae of the amphidromous goby Sicyopterus japonicus, an otolith validation experiment was performed. Larval gobies collected at the river mouth of the Ota River, Wakayama, Japan were immersed in an alizarin complexone (ALC) solution to mark the timing in their otoliths. After being held under natural light conditions for 15 days, they were treated with ALC again to make the second time mark. The number of growth increments between two ALC marks in the otoliths was 14.1 on average, which roughly coincided with the number of days between two ALC treatments. This experiment validated the daily periodicity of otolith growth increment deposition in S. japonicus showing that the otolith increments of the species can be used for age determination with daily precision

Aromatic Metamorphosis of Thiophenes by Means of Desulfurative Dilithiation

A new mode of aromatic metamorphosis has been developed, which allows thiophenes and their benzo-fused derivatives to be converted to a variety of exotic heteroles. This transformation involves 1) the efficient generation of key 1, 4-dianions by means of desulfurative dilithiation with lithium powder and 2) the subsequent trapping of the dianions with heteroatom electrophiles in a one-pot manner. Via the desulfurative dilithiation, the sulfur atoms of thiophenes are replaced also with a carbon–carbon double bond or a 1, 2-phenylene for the construction of benzene rings

Larval transport of the amphidromous goby Sicyopterus japonicus by the Kuroshio Current

Oceanic larval transport of an amphidromous goby, Sicyopterus japonicus, was simulated using a Lagrangian modeling approach to validate the hypothesis that the Kuroshio Current could transport their larvae from Taiwan to northern Japan, which is the geographic range of this species. Simulated particles released at a 50 m depth from the off southernmost part of Taiwan reached Japan from southern Kyushu to northern Japan after 180 days. In contrast, many particles released at 120 m were trapped in eddies in the northwestern part of the subtropical gyre for 90 to 120 days and never reached the southern Japanese coast. These simulations showed that transport at a 50 m depth would enable many larvae to distribute over their entire species range after being transported away from Taiwan. The otolith growth increments of 30 larvae from Wakayama in April to August 2007 showed their oceanic larval duration ranged from 185 to 270 days, suggesting they have sufficient time as larvae for their transport from Taiwan to northern Japan. These results supported the hypothesis of larval transport described above and suggested a possibility that the Kuroshio would play an important role to maintain the apparent lack of population structure of S. japonicus from Taiwan to northern Japan