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Kurikawa, Y.

Publications and source records attributed to Kurikawa, Y..

2 recordsLinked to original sources

Organelle landscape analysis using a multi-parametric particle-based method

Organelles have unique structures and molecular compositions for their functions and have been classified accordingly. However, many organelles are heterogeneous and in the process of maturation and differentiation. Because traditional methods have a limited number of parameters and spatial resolution, they struggle to capture the heterogeneous landscapes of organelles. Here, we present a method for multi-parametric particle-based analysis of organelles. After disrupting cells, fluorescence microscopy images of organelle particles labeled with six to eight different organelle markers were obtained, and their multi-dimensional data were represented in intuitive two-dimensional UMAP (uniform manifold approximation and projection) spaces. This method enabled visualization of landscapes of seven major organelles as well as the transitional states of endocytic organelles directed to the recycling and degradation pathways. Furthermore, endoplasmic reticulum-mitochondria contact sites were detected in these maps. Our proposed method successfully detects a wide array of organelles simultaneously, enabling the analysis of heterogeneous organelle landscapes.

cell biology↗

TAX1BP1 recruits ATG9 vesicles through SCAMP3 binding

Macroautophagy is a cellular process that delivers cytoplasmic material to lysosomes for degradation via autophagosomes. It often involves the selective degradation of ubiquitinated proteins. During selective macroautophagy, five ubiquitin-binding adaptors, p62, NBR1, OPTN, NDP52, and TAX1BP1, form biomolecular condensates with ubiquitinated proteins and recruit ATG9 vesicles, which serve as the initial membrane source required for autophagosome formation. However, the molecular details underlying the cargo/adaptor-dependent recruitment of ATG9 vesicles remain unclear. Here, we show that ATG9 vesicles are recruited by three cargo adaptors: TAX1BP1, NBR1, and OPTN. We also find that ATG9A itself is not the determinant for recruitment by these cargo adaptors, and that TAX1BP1-dependent ATG9 vesicle recruitment is mediated by SCAMP3, a transmembrane protein on the ATG9 vesicles, through binding to the coiled-coil 1 domain of TAX1BP1. These findings provide mechanistic insights into the cargo/adaptor-dependent assembly of ATG9 vesicles in mammals.

molecular biology↗