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Kawagoe, R.

Publications and source records attributed to Kawagoe, R..

2 recordsLinked to original sources

A major update of the genome assembly of Eri silkmoth, Samia ricini.

Indian eri silkmoth, Samia ricini, is a wild silkmoth whose silk occupies a significant economic position. In addition to its importance as an economic animal, S. ricini is also useful as a model species of Saturniidae. National BioResource of Japan (NBRP) maintains a S. ricini strain brought to Japan during WWII via Taiwan. Since we have previously published a draft genome assembly of S. ricini, we have attempted to construct a chromosome-level genome assembly to facilitate genetic studies of S. ricini. We successfully constructed a chromosome-scale genome assembly by exploiting two long-read-based technologies, HiFi reads and optical genome mapping. Furthermore, we performed functional annotations of the genome assembly, i.e., repeat annotation, transcriptome-based gene prediction, ATAC-seq, and PIWI-interacting RNA (piRNA)-targeted small RNA-seq. The assembly harbours 16,226 protein-coding genes and 636 piRNA clusters across three tissues: ovaries, testis, and embryos. ATAC-seq data comprehensively detected open chromosome regions, which will benefit when CRISPR/Cas9-mediated genome editing is conducted.

genomics↗

The Rubicon-WIPI axis regulates exosome biogenesis during aging

Cells release intraluminal vesicles (ILVs) in multivesicular bodies as exosomes to communicate with other cells. Although recent studies suggest an intimate link between exosome biogenesis and autophagy, the detailed mechanism is not fully understood. Here we employed comprehensive RNAi screening for autophagy-related factors and discovered that Rubicon, a negative regulator of autophagy, is essential for exosome release. Rubicon recruits WIPI2d to endosomes to promote exosome biogenesis. Interactome analysis of WIPI2d identified the ESCRT components that are required for ILV formation. Notably, we found that Rubicon is required for an age-dependent increase of exosome release in mice. In addition, small RNA sequencing of serum exosomes revealed that Rubicon determines the fate of exosomal microRNAs associated with cellular senescence and longevity pathways. Taken together, our current results suggest that the Rubicon-WIPI axis functions as a key regulator of exosome biogenesis and is responsible for the age-dependent changes in exosome quantity and quality.

cell biology↗