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S I Ono

Publications and source records attributed to S I Ono.

4 recordsLinked to original sources
PubMed2000

Radiation exposure does not alter metallothionein III isoform expression in mouse brain.

The level of metallothionein III mRNA and protein, a brain-specific isoform of metallothionein (MT), was investigated in the brain of MT-I and -II gene knockout (MT-null) mice exposed to 20 Gy whole-body gamma-irradiation. Because MT-null mice did not express MT-I or MT-II isoforms, the total brain MT content in these mice represented the isoform MT-III only. MT-III protein content was determined by a cadmium-binding assay, and the MT mRNA level was measured by reverse transcription followed by polymerase chain reaction (RT-PCR). Both MT-III protein content and mRNA expression in the brains of MT-null mice were not affected by exposure to whole-body irradiation. These results indicate that mouse brain MT-III expression is not induced by ionizing radiation.

Animals↗
PubMed1999

Cell-substrate interactions in cnidaria.

Studies on morphogenesis and regeneration in cnidarians have a long history, and the importance of cell-ECM (extracellular matrix) interactions for these processes has been well recognized and studied since the middle of the 20th century. Cnidarians have a life cycle with a larva, a polyp, and often a medusa generation. In the medusa, the ECM (mesoglea) is very prominent and essentially shapes the animal. In the larva and the polyp, the ECM is a thin layer. Some of the ECM components known from vertebrates have been identified in cnidarians by immunohistochemistry, electron microscopy, rotary shadowing, biochemistry, and molecular cloning. In vivo and in vitro experiments suggest that the cnidarian ECM plays a role in cell migration and morphogenesis comparable to that known from other developmental systems. In the fresh water polyp Hydra, regeneration of body patterns and migration of nematocytes seems to require the presence of ECM ligands and the corresponding cell receptors. In hydrozoan medusae, DNA replication and the stability of the differentiated state of isolated tissue can be influenced by altering the properties of the ECM substrate. When cultured, most cnidarian cells survive only when attached to ECM substrates, they rarely divide and die within short times.

Animals↗
PubMed1998

Changes in brain metallothionen and zinc during development in transgenic mice.

The developmental alterations in metallothionein (MT) proteins and zinc (Zn) were investigated in brains of two transgenic strains of mice. MT protein was measured by a cadmium binding assay and Zn by atomic absorption spectrophotometry. MT proteins were expressed at birth (day 1) both in MT-I overexpressing transgenic mouse (MT-I*) and MT-null (expressing only brain specific isoform, MT-III) transgenic mouse. MT proteins level (mainly MT-I) in MT-I* was 16.1 microg/g at birth, and thereafter increased with age to a maximal adult level of 55.3 microg/g (day 60). Zn level in MT-I* also increased from 8.43 microg/g (day 1) to 20.7 microg/g (day 60) with age. MT protein (MT-III) in MT-null mouse was 9.71 microg/g at birth and remained relatively unchanged during development. Zn level in MT-null mouse at birth was 9.46 microg/g and also remained unchanged during development. The similar alterations in MT isoforms and Zn in brain during development suggest that MT isoforms may act as a Zn binding protein.

Age Factors↗