Involved in aging, oxidative stress response, and in the regulation of mitochondrial biogenesis. Inactivation of UTH1 increases life span, leads to higher resistance to heat stress and to hydrogen peroxide, and increases sensitivity to the superoxide radical-generating drug paraquat and to copper. Also required for the selective autophagic degradation of mitochondria (mitophagy) in response to nitrogen starvation. Involved in the remodeling of the cell wall during the various phases of yeast culture development and under various environmental conditions and plays a role in septation. Involved in cell sensitivity to boric acid (By similarity). Non-covalently bound to the cell wall. Belongs to the SUN family.