As budding yeast makes gametes, Tom70 helps exclude nuclear pore complexes from the new cells. A peer-reviewed study links this selective sorting to contacts between mitochondria and the nuclear envelope. Removing the protein disrupts pore exclusion while leaving several other aging-associated components unaffected, revealing distinct routes for handling nuclear material in this yeast model.
Budding yeast selectively keeps nuclear pore complexes out of newly forming gametes with help from Tom70, a protein on mitochondria’s outer membrane. A single peer-reviewed study in Saccharomyces cerevisiae links this sorting to physical contacts with the nuclear envelope. During gamete formation, material excluded from the new cells accumulates in a separate nuclear compartment before being broken down.[1]
Removing TOM70 disrupted the exclusion of nuclear pores, the protein assemblies that control passage between the nucleus and surrounding cytoplasm. The exclusion of protein aggregates associated with aging, along with nucleolar material, remained largely intact. The selective effect emerged through live-cell imaging and genetic experiments. Disrupting the general import of proteins into mitochondria failed to reproduce this pattern, supporting a function beyond Tom70’s usual import role.[1]
During the second meiotic division, Tom70 accumulated around the excluded region and recruited Cnm1, a protein that connects mitochondria with the nuclear envelope. Without CNM1, some of the sorting defects returned. Experiments with altered Tom70 domains connected membrane tethering with pore exclusion, while leaving room for additional contact mechanisms. The findings concern inheritance during yeast gametogenesis and do not establish a human rejuvenation intervention.[1]
