タンパク質寿命が制御するシン・バイオロジー

Proteasomes and lysosomes are key determinants of intracellular protein lifetime. However, it is largely unknown how the function of these degradation apparatus is maintained. Ubiquitination is involved in various cellular processes including proteins degradation and autophagy. It has been long thought that targets of ubiquitination are limited to proteins. We have recently discovered that endo/lysosomal phospholipids are ubiquitinated. In this study, I aim to uncover the molecular mechanism of lipid ubiquitination and its role in the regulation of lysosomal functions. To understand the quality control mechanism of proteasome, I focus on autophagic degradation of proteasomes and investigate its molecular mechanism and role in the regulation of global protein half-life. These analyses will further advance our understanding of the regulatory mechanisms of protein lifetime.

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