title: Motility and segregation of Hsp104-associated protein aggregates in budding yeast.
abstract: During yeast cell division, aggregates of damaged proteins are segregated asymmetrically between the bud and the mother. It is thought that protein aggregates are cleared from the bud via actin cable-based retrograde transport toward the mother and that Bni1p formin regulates this transport. Here, we examined the dynamics of Hsp104-associated protein aggregates by video microscopy, particle tracking, and image correlation analysis. We show that protein aggregates undergo random walk without directional bias. Clearance of heat-induced aggregates from the bud does not depend on formin proteins but occurs mostly through dissolution via Hsp104p chaperon. Aggregates formed naturally in aged cells also exhibit random walk but do not dissolve during observation. Although our data do not disagree with a role for actin or cell polarity in aggregate segregation, modeling suggests that their asymmetric inheritance can be a predictable outcome of aggregates' slow diffusion and the geometry of yeast cells.
authors: Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA.
authors: Chuankai
authors: C
authors: Zhou
authors: Brian D
authors: BD
authors: Slaughter
authors: Jay R
authors: JR
authors: Unruh
authors: Amr
authors: A
authors: Eldakak
authors: Boris
authors: B
authors: Rubinstein
authors: Rong
authors: R
authors: Li
mesh_terms: D000199:Actins / Q000378:metabolism; D002455:Cell Division; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D000199:Actins; D006360:Heat-Shock Proteins; D029701:Saccharomyces cerevisiae Proteins; C070972:HsP104 protein, S cerevisiae