Shintaro Iwasaki 교수

Ribosome movement is not always smooth and is rather often impeded. For ribosome pauses, fundamental issues remain to be addressed, including where ribosomes pause on mRNAs, what kind of RNA/amino acid sequence causes this pause, and the physiological significance of this attenuation of protein synthesis. Here, we survey the positions of ribosome collisions caused by ribosome pauses in humans and zebrafish using modified ribosome profiling. Collided ribosomes, i.e., disomes, emerge at various si

Ribosomes often encounter obstacles during translation elongation and thus collide with each other. Disome profiling, an optimized ribosome profiling method, specifically sequences the long ribosome footprints generated from collided ribosomes produced by the ribosome pause and thus allows the survey of sites in a genome-wide manner. This protocol details the procedure from lysate preparation of human tissue cultures and zebrafish embryos to sequencing library construction. For complete details

Although decapping is an important process in eukaryotic mRNA turnover, little is known about this process in plants. Here, we identified Arabidopsis thaliana decapping proteins AtDCP1 and AtDCP2 and showed that (I) AtDCP2 is an active decapping enzyme, (II) AtDCP1 interacts with itself, (III) AtDCP1 and AtDCP2 are localized to cytoplasmic foci (putative Arabidopsis processing body), and (IV) AtDCP1 and AtDCP2 are essential for post-embryonic development. Our findings provide new insights into t

Synthesis and degradation of cellular constituents must be balanced to maintain cellular homeostasis, especially during adaptation to environmental stress. The role of autophagy in the degradation of proteins and organelles is well-characterized. However, autophagy-mediated RNA degradation in response to stress and the potential preference of specific RNAs to undergo autophagy-mediated degradation have not been examined. In this study, we demonstrate selective mRNA degradation by rapamycin-induc

Three different types of lingual papilla were observed by scanning electron microscopy on the dorsal lingual epithelium of the lizard Gekko japonicus. Dome-shaped lingual papillae were located at the apex. Flat, fan-shaped lingual papillae were seen in the widest area of the lingual body. Long, scale-like lingual papillae were arranged on the latero-posterior dorsal surface. At higher magnification, microvilli and microridges were seen to be widely distributed over the surface of the papillae. B

Tongues were removed from fetuses of mice on the 15th day of gestation (E15), from newborns (P0), and from juveniles on the 7th day (p7) and on the 21st day (P21) after birth for examination by light microscopy and transmission electron microscopy. In the fetuses at E15, no rudiments of filiform papillae were visible on the dorsal surface of the tongue. No evidence of keratinization was recognized throughout the entire dorsal lingual epithelium. At P0, rudiments of filiform papillae were compact

Various stressors such as viral infection lead to the suppression of cap-dependent translation and the activation of the integrated stress response (ISR), since the stress-induced phosphorylated eukaryotic translation initiation factor 2 [eIF2(αP)] tightly binds to eIF2B to prevent it from exchanging guanine nucleotide molecules on its substrate, unphosphorylated eIF2. Sandfly fever Sicilian virus (SFSV) evades this cap-dependent translation suppression through the interaction between its nonstr

The epithelium of the lingual dorsum of the mongoose, Herpestes edwardsi, was composed of two main areas: the interpapillary area, characterised by the absence of keratinisation; and the papillary area, characterised by hard keratinisation. The number of tonofibrils in the cytoplasm gradually increased, and the volume of the individual cells also increased, from the germinal layer to the intermediate layer of the interpapillary epithelium. No keratohyalin granules were recognised in these cells.

A review of MR and CT images in five patients, 8 months to 22 years old, diagnosed as having tuberous sclerosis, revealed linear abnormalities in the cerebral white matter. A linear abnormality connecting a subependymal nodule to a subcortical lesion was shown in two patients as an area of hypointensity on T1-weighted MR images and as an area of hyperintensity on T2-weighted images. These appeared as faintly high-density areas on CT images. Seventeen linear abnormalities extending from the ventr