Through investigation of the behaviors/fates of fluorescent proteins inside lysosomes, we developed a signa-retaining autophagy indicator (SRAI). We localized SRAI into mitochondria (mito-SRAI) to quantitatively measure mitophagy. We apply the new tool in a high-throughput in vitro screen for chemical inducers of mitophagy and in a mouse model of Parkinsons disease.

The researchers have successfully designed a novel three-dimensional staining and imaging technique, CUBIC-HistoVIsion, based on the physicochemical properties of biological tissues as an electrolyte gel. They demonstrated the staining of whole mouse brains, human brains, and whole marmoset bodies. This technique thus allows detailed analysis of brain circuits with cellular resolution.

In this study, we discovered galactosylated cholesterol as a novel brain sterol metabolite. We found that glucocerebrosidases, whose involvement in galactose metabolism was not previously reported, catalyze a transgalactosylation reaction from galactosylceramide to cholesterol to synthesize galactosylated cholesterol.

Production and deposition of amyloid β peptide (Aβ) are the initial steps of pathogenesis of Alzheimer disease (AD). This study successfully identified CIB1 as a negative regulator of Aβ production by CRISPR/Cas9 screening. Furthermore, single-cell RNA-seq revealed the decreased CIB1 mRNA in early stage of AD patients, indicating that CIB1 is involved in AD pathogenesis.

This study revealed the association between Parkinson’s disease (PD) and the prosaposin saposin D domain (PSAP-D). iPS cells from patients with PSAP-D mutation showed an accumulation of alpha-synuclein. Mouse with PSAP-D mutation showed dopaminergic neurodegeneration. Furthermore, two variants in the intronic regions of the PSAP-D in sporadic PD had significantly higher allele frequencies.