Biology subjects

Yang, E. J.

Publications and source records attributed to Yang, E. J..

2 recordsLinked to original sources

bioRxiv2021

Identification of a novel modulator of the actin cytoskeleton, mitochondria, nutrient metabolism and lifespan in yeast

In yeast, actin cables are F-actin bundles that are essential for cell division through their function as tracks for cargo movement from mother to daughter cell. Actin cables also affect yeast lifespan by promoting transport and inheritance of higher-functioning mitochondria to daughter cells. Here, we report that actin cable stability declines with age. Our genome-wide screen for genes that affect actin cable stability identified the open reading frame YKL075C. Deletion of YKL075C results in increases in actin cable stability and abundance, mitochondrial fitness, and replicative lifespan. Transcriptome analysis revealed a role for YKL075C in regulating branched-chain amino acid (BCAA) metabolism. Consistent with this, modulation of BCAA metabolism or decreasing leucine levels promotes actin cable stability and function in mitochondrial quality control. Our studies support a role for actin stability in yeast lifespan, and demonstrate that this process is controlled by BCAA and a previously uncharacterized ORF YKL075C, which we refer to as actin, aging and nutrient modulator protein 1 (AAN1).

cell biology↗

bioRxiv2021

A role for cell polarity in lifespan and mitochondrial quality control in the budding yeast Saccharomyces cerevisiae

Babies are born young, largely independent of the age of their mothers. Mother-daughter age asymmetry in yeast is achieved, in part, by inheritance of higher-functioning mitochondria by daughter cells and retention of some high-functioning mitochondria in mother cells. The mitochondrial F-box protein, Mfb1p, tethers mitochondria at both poles in a cell cycle-regulated manner: it localizes to and anchors mitochondria to the mother cell tip throughout the cell cycle, and to the bud tip prior to cytokinesis. Here, we report that cell polarity and polarized localization of Mfb1p decline with age in S. cerevisiae. Moreover, deletion of BUD1/RSR1, a Ras protein required for cytoskeletal polarization during asymmetric yeast cell division, results in depolarized Mfb1p localization, defects in mitochondrial distribution and quality control, and reduced replicative lifespan. Our results demonstrate a role for the polarity machinery in lifespan through modulating Mfb1 function in asymmetric inheritance of mitochondria during yeast cell division.

cell biology↗